Electricity Saving Tips For Homes And Offices

Ideal Air Conditioner temperature for electricity savings

By on January 18, 2017
Hindi Translation: बिजली बचत के लिए आदर्श एयर कंडीशनर तापमान

Buying an air conditioner once considered a sign of luxury, is now becoming quite common in India. Many urban homes are equipped with air conditioners in one or more rooms. But everyone who owns an air conditioner knows that it comes at the cost of increasing electricity bills. Although cooling does take a lot of electricity but taking effective steps can surely get it down. One of the main things that can help is maintaining the right temperature for the air conditioners.

How does an air conditioner work?

For most people, air conditioner just throws cool air at the temperature one sets it at. But does it really work that way? In fact air conditioner during cooling process, takes the indoor air, cools it  by passing it through evaporator coil and throws it back in the room. It is quite opposite to how our good old air coolers used to work. Air coolers used to take outside air, cool it with water and throw it in. But air conditioners just work on internal air.

How does the thermostat work?

If you set the thermostat at 18oC (64.5oF), does it mean that the air conditioner will cool the room faster than if set at 25o(77oF)? No. The thermostat just checks the temperature of the air inside the room and stops the compressor when the temperature reaches the desired level. This means that the compressor will work longer if the temperature is set to a lower level, i.e it will work more and use more electricity if temperature is set to 18oC (64.5oF) than if it is set to 25oC (77oF). This is because it will take less time for air to reach to 25oC (77oF) than 18oC (64.5oF) as the compressor is working with the same power or wattage.

What happens when the compressor stops?

The air conditioner just blows the fan when the compressor stops and thermostat reaches the desired temperature level. At this stage the electricity consumption is only for the fan which is running and not for the compressor. The compressor will start again when the thermostat detects that the temperature has increased again from the levels that are set. Compressor is the most electricity consuming component of an air conditioner.

What factors impacts electricity consumption of Air Conditioner?

There are 4 factors that influence the electricity load:

1) Indoor air temperature

2) Outdoor temperature

3) Thermal insulation of the room

4) Temperature setting of the air conditioner.

If the difference between temperature desired and indoor/outdoor temperature is huge, then the air conditioner will need lot more electricity to cool the indoor air to desired temperature as the compressor will run for longer duration. If the temperature is set at 18oC (64.5oF) and the outdoor temperature is 38oC (100oF) then the electricity required will be lot more than when thermostat temperature is 24oC (75oF) and outdoor temperature is 38oC (100oF). As per study by ACEEE (American Council of Energy Efficiency Economy), increase of each oC can save 3-5% of units consumed. This can considerably bring down the units consumed per month in the electricity bill.

What is the ideal temperature that should be set on thermostat?

Having said that, increase in temperature does not reduce the comfort level. In fact as per ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers), the ideal temperature for thermal comfort is between 23.5oC (74.3oF) and 25.5oC (78oF) in summers (depends on several factors as listed on wikipedia). Thus setting the temperature to 24oC (75.2oF) saves on electricity bill and provides good comfort. Using ceiling fans along with air conditioners can additionally help in increasing the thermostat temperature.Air Conditioner Temperature Infographic

Does “Quick Cool” option in Air Conditioners help?

Setting an air conditioner to quick cool sets it’s temperature to 18 or 16 oC (64.4oF or 60.8oF. This means that the compressor stops only when indoor temperature reaches this level. But while coming down from 35 or 40 oC (95oF or 104oF) it would have surely crossed 24oC (75.2oF) which is a comfortable temperature. So using “Quick Cool” option does not help because more electricity is used to get the temperature down to 18oC (64.5oF) whereas compressor would have stopped in between if the temperature was set to 24oC (75.2oF) thereby consuming less electricity.

How do old air conditioners without thermostat work? 

Old air conditioners without thermostat have high, medium and low cool options. As we learnt earlier that compressors of air conditioners work in binary mode (either they are on or off), an air conditioner without thermostat does not control air temperature. The high, medium and low options just changes the air conditioner fan speed. High means that air conditioner will throw more air and low means that the fan speed will be slow.

Here is a short video for tips to reduce power consumption of air conditioner in India



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  • Ram

    Hi Abhishek,
    There is confusion on the choice of inverter ac 1.5 Ton. Samsung and LG are quite identical in their features. But they dont have copper coil.
    Samsung AR18MV3HETQ, LG JS-Q18AUXA or LG JS-Q18NPXA and Voltas 183VEYA. ISEER is ~ 3.6
    Hitachi, Daikin are good but costly. The general suggestion i received is to go for a 3 star inverter ac for home use.
    I searched that the LG model has a low dB value and good, but am told Samsung is a newer model with more filters and more warranty.

    My friend has a Voltas 1.5 T BEE 5* non-inverter. It is used at 28 degrees all night. Also uses it with a ceiling fan on. Is that a good way to use ?

    Anyways i am really confused and if samsung/Lg offer same features for a Inv ac i dont see the need to buy a Hitachi/Daikin with copper spending 15k more.
    Please let me know your recommendations.

    And Your website is an excellent source for many queries. Thankyou.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Ram,

      LG does have BEE 3 star rated copper inverter AC. You can check LG JS-Q18AUXA (ISEER of 3.86). I am not able to find it on Amazon or Flipkart to give you a price/link of the same. Any LG model with “U” in the name has copper.

      Also Godrej GSC 18 MINV 3 RWPM (Flipkart Link: http://fkrt.it/wjh!h!NNNN ) is a copper model with ISEER of 3.79

      Voltas 183V IY (Amazon Link: http://amzn.to/2n986GN ) and Voltas 183V EY (Flipkart Link: http://fkrt.it/wLU0C!NNNN ) are also copper with ISEER of 3.7

      Blue Star 3CNHW18NAFU with ISEER of 3.67 is also copper. All these are BEE 3 star rated ACs with copper condenser.

      Keeping AC at 28 is great way of saving electricity. Also if your roof does not get direct sunlight, then using ceiling fan is also better.

  • riyamubi

    What will happen if I set my AC Temperature at 28 degree Celsius. Will it save in money or not

    • https://www.bijlibachao.com Abhishek Jain

      It will certainly save money. Higher the temperature that you keep, more will be the savings.

  • Prakash

    Am using inverter ac 1.5 ton . when my set temperature reaches i.e 25 degree after few mins it reach 24 degree and come down to 25 again , then there is a cut off for 40 to 50 seconds or a little more . Is this cut off normal for inverter a.c ? and next my room don’t get enough cool when I set temperature at 25 degree my room size not so big am sure 1.5 ton is far more enough. what’s ur explanation for this ? ( my outside temperature is almost 30 to 32 degree when I side my a.c to 25 degree.

    • https://www.bijlibachao.com Abhishek Jain

      Inverter AC should not cut off unless the outdoor temperature is same as indoor temperature and there is no heat to remove. Usually the temperature that the AC measures is the temperature at the grill (or the indoor unit).

      Also ACs are usually meant to cool only 1 room and not two rooms. It is not like an air cooler. The impact of AC usually is about 10 ft from the indoor unit (or a bit more if it is a 2 ton AC). So the cold air from one room will not go to the other room. And in general it is not advisable to keep a room open while using AC (for effective cooling and low electricity consumption).

    • Prakash

      Yes there is a cut off when it reaches out side temperature . My ac model LG JS Q18AUXA. some times if I set temperature at 26 degree at afternoon I can see compressor cut off. Why my ac always cut off at 26 degree even at night or noon ?

    • https://www.bijlibachao.com Abhishek Jain

      Depends on outside temperature. And it is surprising because my inverter AC does not cut off at 26-27. It usually does when it is set to 27-28 at night (not at noon). Because in Mumbai at night the temperature comes down to 28-29 outside and so setting the AC at 27-28 does cut it off at times. But in noon when outside it is 34, it does not cut off.

    • Prakash

      I made a call to LG ( Tamil Nadu Regional ) chief engineer and Samsung Chief Engineer , they both said cut off is very common on inverter a.c @ high temperature that is above 26 degree . Last night I checked my ac with 24 degree where there is no cut off until I made some customs settings to e – saver mode after 6 hrs. E – saver mode keeps on increasing the temperature for every 1 or so and they settled at 26 degree final where cut off take place and some times I can hear the fan runs very slow just not too over cool the room.

    • https://www.bijlibachao.com Abhishek Jain

      The compressor will stop when there is no heat to remove from the room.

    • Prakash

      So is it noting harm when compressor off due to no heat to remove from the room ?

    • https://www.bijlibachao.com Abhishek Jain

      Yes. There should be no harm with compressor being off.

  • jismon

    i purchesed a mistubishi ac with mr slim what you men by mr slim.and i noticed that it never cutt of set temp 23 for 3 hr use it not cutt off .it is not an inverter model normalaly ac are cut off 30 min of operation and restart afetr some time by archiving temprature it dinot cut off

    • https://www.bijlibachao.com Abhishek Jain

      MR Slim is a VRF (Variable refrigerant flow) Hot and Cold AC technology. It is explained well on this video: https://www.youtube.com/watch?v=QovhagNTyaE …… it is very similar to inverter technology and it will not cut off the compressor (like in inverter tech).

  • mc

    How does drop in room temperature affect air con energy consumption? Lets say room temperature drop 5 degrees after roof painted with thermal insulation paint , if all other factors remain the same how much air conditioning energy can be saved ?

    • https://www.bijlibachao.com Abhishek Jain

      If suppose your outside temperature is 45 and you keep your AC at 25 then your electricity consumption is proportional to (45-25) = 20 …. let’s say 20x

      If you put a thermal insulation that reduces the temperature by 5 degrees then AC will have to bring down the temperature from 40 to 25 …. so difference is 15 and so energy consumption is about 15x

      so savings is of 5x …. in percentage it becomes (5/20)*100 = 25 ……

      However, firstly when outside temperature is 45 …. your indoor temperature will not be 45 ….. it would be less ….. and then it’s not everyday that you have a outside temperature of 45.

      Suppose your room temperature without insulation typically remains at 35 (when outside temperature is 45) …. and so your electricity consumption is (35-25) = 10x

      and you reduce by 5 degrees so it becomes 5x ….. then your saving increases to 50%.

      So a lot depends on your outside temperature and existing thermal conductivity of the wall and also the temperature at which you keep the AC.

  • dasadia

    Respected sir,
    I bought my new Hitachi AC but after a week the gas got leaked. So I filled new gas from a local AC repairer.
    Can it cause any effect on energy consumption..???

    • https://www.bijlibachao.com Abhishek Jain

      If it is cooling properly, then it should not cause any impact on energy consumption.

  • Vincent

    I have a doubt. Running the AC in 16 degree at different intervals for about 2 to 3 hours in a night will save electricity?? or running the whole night with 25 to 26 degrees is the better option??

    • https://www.bijlibachao.com Abhishek Jain

      Running the AC whole night with 25-26 will be more comfortable and energy saving.

    • vincent

      Thanks for your clarification

  • Newaz
    • https://www.bijlibachao.com Abhishek Jain

      You should not be doing that. It will consume more electricity.

    • Newaz

      Thanks Abishek Thanks a lot

  • Karthikeyan R

    Hey Sir,

    i bought 1 ton Whirlpol AC 3 months before. am from Taminadu – madurai. during the installation they did mistake so the gas leaked. they filled the gas again, but i got very low cool. again filed the gas after using vacuum machine. now i can feel the cool. but not sure whether its working fine or not. so i checked the timing. pls go thru the below info and give your thought -either my AC is fine or not

    my room size is 10X11, i started my AC @ 9:30 PM , the room temp was @ 31.5, i set 25 degree in AC. after 90 mins it reached the 25 degree. with in 3 mins, the AC started again, and i set the 24 degree. i waited another 90 mins, but it did not cut off.

    i used a thermometer to check the grill temperature by another day. after 30 mins the grill temp was 10.5 degree, after 1 hour it reach 8.7 degree.

    one more info, in the same house , my brother’s room also having the same AC installed on same day. when i checked in the Grill temp of the AC, it can reach 10.5 with in 15 mins and in 45 mins it reach 7.4 degree.

    pls check and suggest , either my AC is working fine, or i should raise the complain again.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Karthikeyan,

      A lot depends on the cooling capacity of the AC and also the heat load of your room. Two rooms will have very different heat loads and two ACs can have different cooling capacity. I would suggest you to read this article on our website to see how an AC works: http://www.bijlibachao.com/air-conditioners/air-conditioner-work-laymans-explanation.html

      As long as you are feeling comfortable and electricity consumption is not high, the AC is serving its purpose. If it is either not comfortable or consuming high electricity, you need to get alarmed.

    • Karthikeyan R

      Dear Sir,

      Thanks for the reply. i understand about the head load of room . but my brother room and my room are ideally same. only one different is direction. but i checked the Grill temp @ 9:30PM so i think, the sun effects does not affect it.

      can you pls give your suggestion about the below. is the below difference normal or any issue there in my room AC ?

      i used a thermometer to check the grill temperature after 30 mins the grill temp was 10.5 degree, after 1 hour it reach 8.7 degree. it never reach less than 8

      my brother’s room also having the same AC installed on same day. when i checked in the Grill temp of the AC, it can reach 10.5 with in 15 mins and in 45 mins it reach 7.4 degree.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Karthik,

      It is difficult to comment.

  • Eduardo Fracassi

    Hi have you published the demonstration of the Percentage Savings formula? Where? We need the formula’s rationale for an important presentation. We obviously quoted your work with the corresponding reference citation.

  • planes creator


  • Anonymous

    Is there a chart that shows monthly kwh consumed for each city (Bangalore, specifically)? Of course there would be a lot of assumptions, but maybe you could help me calculate the energy consumed for a 150 sqft room with a concrete wall exposed to the East (partly shielded by a balcony) on one face one other wall exposed South East and 2 interior walls – since it is an apartment on the 2nd floor it is well shielded above and below. Assuming 35 degrees outside temp and setting the inside to approx 25 during the daytime and another calculation for night time where temperatures are more likely to be around 28 degrees. Humidity is very high at 90% or greater most days.

  • Jewan Joga

    I have 1 ton DC inverter AC (4.8A, 1100W) in my 8×11 room. I usually set 28°C, auto mode with 11hrs running. normally in these days night time temp start from

    33°C RealFeel® 39°C. Can you estimate my monthly consumption.

    • https://www.bijlibachao.com Abhishek Jain

      Extremely difficult to make an accurate guess. But at a very high level it should not consume more than 4-5 units in 11 hours.

  • Vipin

    Hii Abhishek,

    I have one query which mode save more electricity during night time,
    Auto Mode Or Sleep Mode?
    I have 1.5T Voltas Split AC.


    • https://www.bijlibachao.com Abhishek Jain

      Sleep mode will save more electricity.

  • Aniket

    Hi Abhishek
    I have bought a Bluestar 2.5 tonne 5 star ac. The other day I adjusted it to the Dan mode n continued the same for quite sometime. Would that be a problem in the long run, also it is necessary to switch on the cool or the auto mode. I am in mumbai n thanks to monsoon the climate is quite bearable. Is is OK to run the ac on fan mode only.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Aniket,

      In Fan mode just the AC fan is used. The compressor is not switched on in this mode. So the AC does not cool the air, it just circulates the air. There is no problem in using this mode.

    • Sagar Chaudhari

      Hi Abhishek,
      In the case of fan mode, is the electricity consumption of an 1.5 ton AC or any AC for that matter equal to that of a common ceiling fan?
      And can use of AC omit the need of a ceiling fan?

    • https://www.bijlibachao.com Abhishek Jain

      Fans in ACs are just blowers. They consume more power than a regular ceiling fan. The one we measured consumed about 200 Watts. I do not think AC can omit need of ceiling fan.

  • Lalit Leo

    hi Abhishek ji,
    I have purchased Carrier Midea Flair 1.5 ton split ac with 5 star rating. i live in Jaipur, Rajasthan. I live on the top floor. Outdoor unit installed by the side of a wall, so no direct sunlight on the outer unit, but the ceiling get too hot as it is the top floor. my room size is 12*12. Can you tell me please what will be the ideal setting for my ac to save electricity bills. It has auto, cool, dry, fan mode.I am running it on auto mode at 27 – 28 degree.

    • https://www.bijlibachao.com Abhishek Jain

      Run it in cool mode on 27-28 degrees. That would be better.

  • Rohit Dabhade

    Hello sir below comment is also mine
    point 1 is wrong .. its
    1: At 25 degree, compressor on for 6 minutes and off for 1 minute and 20 sec

  • Rohit Dabhade

    Hello sir the below comment posted are also mine . I have calculated on and off time of compressor.
    Here as follows
    1: At 25 degree, compressor on for 5 minutes and off for 1 minute and 20 sec
    2: At 26 degree, compressor on for 7 min and off for 50 sec
    3: At 27 degree, compresor on for 5 min and off for 20 sec
    Plz do reply waiting for ur response
    and thanks for this website .

    • https://www.bijlibachao.com Abhishek Jain

      5-7 run time is less, but not too less. But are you sure it remains off just for 20 seconds? That’s too less.

    • Rohit Dabhade

      Yes its 20 seconds.. compressor off at 27 degree.
      Then what u suggest at what temperature should i keep my air conditioner to maintain its efficiency ?

    • https://www.bijlibachao.com Abhishek Jain

      Better keep it at 24-25.

  • Rohit Dabhade

    Hello sir, my room is 15*10 and i use 1.5 ton voltas ac and i keep my ac temperature at 27 degree in cool mode. Is it good for my ac ? … will it affect the air conditioner efficiency ?

    • https://www.bijlibachao.com Abhishek Jain

      27 degrees is a good temperature. Which city do you live in?

    • Rohit Dabhade

      i live in Mumbai..
      But i have also commented on 25,26 and 27 degree.
      Plz go through above comment also
      and thanks for ur reply

  • pacific ice

    i have a voltas 1.5 ton ac. the remote is exactly similar to what you are holding in the video. Can you please tell me how should i use the various modes? and is it helpful to use sleep mode and the energy saving mode while sleeping at night ?

    • https://www.bijlibachao.com Abhishek Jain

      Use cool mode during the day as it is good for saving electricity. And at night sleep mode or energy saving mode is better. Choose the one which is more comfortable for you. In Sleep mode it will increase temperature throught the night while in energy saving mode it will turn off for some time during the night.

  • Kutubuddin Madraswala

    sir i am buy today lg 1.5 ton ac which temperature use for benefit for energy savings my light bill given me some advice & also auto mode is best for saving or cool mode is best for saving

    • https://www.bijlibachao.com Abhishek Jain

      Use AC at 25 degrees for most energy savings. Cool mode is better than auto mode.

  • Aradhana chaudhary

    Hi i had purchased five star LG himalaya cool LSA5SU5A of 1.5 ton…
    And i use to run it almost 20 hrs in a day at 25 to 27 degree temperature with power saving mode.
    My electricity bill of this month is 3500 for the AC only. I think m saving on electricity with my LG AC. Is it..?

  • h215

    Hi. I m using SHARP 0.75 ton window AC on rent basis. It’s thermostat controller is showing no. 1 to 9
    Could u plz tell me..wats that mean..and how we can manage so that it consumes less energy..
    M attaching image of that.

    • https://www.bijlibachao.com Abhishek Jain

      1 to 10 is for thermostat. One is lowest cooling output, and 10 is highest cooling output. Keep the number as low as it is comfortable for you for electricity savings. At 10, electricity consumption would be highest.

    • Loving Sustainability

      What’s the difference between the cool settings and fan?

    • https://www.bijlibachao.com Abhishek Jain

      Sorry I did not understand your question. Do you want to understand difference between cool mode and fan mode in the AC? If yes then in Fan mode only the fan runs and compressor does not. It will not cool the air. While in cool mode, compressor also runs and thus it cools the air.

  • Tejas

    What is best mode to use AC effectively… Fan with high speed and set temp of 24 or fan with slow speed and set temp of 2 consider ambient temp to be 35. Does the speed of fan affect the AC performance/ effectiveness.

    Read about the fan speed consumes 30%of total power. But the way fan is used in AC also plays vital role for geeting the same comfirt with lesser power.

    • https://www.bijlibachao.com Abhishek Jain

      Depends on how hot your ceiling gets. If you have more floors above your room then fan at high speed and higher temperature can save you electricity over fan at slow speed and lower temperature. But if you have ceiling facing direct sun, then better not use the Fan.

    • Tejas

      Thanks abhishek, there are 2 floors above my room. My question is related to fan that operates with AC. Is there any benefit of dissipating heat of compressor/coil via fan speed variation.

    • https://www.bijlibachao.com Abhishek Jain

      Fixed Speed ACs have a fixed cooling capacity. A 1 ton AC removes heat at rate of 12000 BTU/hr when the compressor is running. The heat dissipation depends on the cooling capacity. Fan speed does not impact the cooling capacity of the AC.



    • https://www.bijlibachao.com Abhishek Jain

      Hi Aashish,

      Typically the numbers reported are in test conditions, but it should not vary at such a large scale. If you do notice such thing, you can always report it back to BEE so that star label for any model is validated. I would also suggest that you call godrej and ask them to check the product.

  • AC guy

    I have a Voltas 1 ton AC that does not cool as much as my other ACs. The service people from Voltas told me that I need to keep the swing pointed at the bottom and then only will I get cooling otherwise it won’t work. I feel they are trying to hide the fact that the AC is defected. Please help Abhishek. Thanks a lot.

    • https://www.bijlibachao.com Abhishek Jain

      I do not think that they have given you the right answer. One of the reason it does not cool as much would be because the cooling capacity of the model may be lower than the cooling capacity of other ACs. I hope you are not comparing 1 ton with 1.5 ton (1.5 ton will have more cooling capacity). And swing will just help in distributing air evenly. It can just help in spreading cooling all around. But then it does not help in cooling faster.

  • Kool Addy

    When compressor reaches desired level n stops…then when it starts again…i heard it will consume more power ..is that true ?

    • https://www.bijlibachao.com Abhishek Jain

      Everytime compressor starts, it consumes more power.

  • Sweta

    For a 150 sq ft room , if outside temperature is 43 degree then how much time a 1.5 ton AC should take to cool down room to 25 degree?

    • https://www.bijlibachao.com Abhishek Jain

      Difficult to tell. Depends on the heat load.

  • Bobby Kumar

    I baught a new blue star window ac 1.5 ton 5 star but i want to know its features about
    Cool, Dry, Fan mode,
    On/off timer
    Sleep mode
    Energy saver

  • Bilal Khalid

    How does the speed of blower (installed in indoor unit) effects the air conditioning? For example if the temperature is set to 26C and blower speed is at low level. now the blower speed is set to high level. what does this effect air conditioning?

    • https://www.bijlibachao.com Abhishek Jain

      The speed of the blower helps in faster and more coverage in the room. If the air flow is fast, it will reach a longer distance and thus will quickly cool places that are far away from the AC. If the air flow is slow, it will reach longer distance slower and in fact at times may not reach all places as well. That is why it is preferred to install an AC in the most central location of the room so that it can cover all places.

    • Bilal Khalid

      As we increase the speed of blower the convective heat transfer increases in evaporator. so my question is does blower speed effects heat transfer rate? suppose you place a thermometer in front of air out window (in evaporator) will it sense the same temperature in both cases (low and high speed of blower)

  • Imran Warind

    Hi.. Thanks for such a wonderful article.. I just had one question which I have not been able to find a proper answer to yet.. I have a 1 Ton voltas inverter ac in my 10×10 bed room and I guess it’s doing OK.. And i generally prefer to keep the swing off and keeping the air vents fixed directed down to the bed.. But someone told me keeping the swing off consumes more electricity and so I should keep it on.. I haven’t been able to really find any correlation between swing mode and the power consumption of the ac anywhere online .. Can you please shed some light on the matter? I’ll be grateful.. Thanks

    • Anupinder Singh

      It’s correct swing mode will decrease power consumption, here is the reason, swing mode will maintain uniform temp in room, so air sucked by blower is cooled so it will interpret that room is cool, and cutoff compressor

    • https://www.bijlibachao.com Abhishek Jain

      Hello Mr Singh,

      I do not see any reason for grill temperature to be high if swing is off, although I agree that keeping the swing on will cool the whole room (which esentially means more electricity consumption). So I do not agree with your analysis.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Imran,

      If you keep swing on, it will cover more area of the room and will consume slightly more electricity. I do not think keeping swing off will consume more electricity. In fact keeping swing on will consume more electricity.

  • Shubham Das Gupta

    Can I keep the AC at 30C without causing it any harm? And will it be saving more energy as opposed to keeping it at 23-25C? Mine is an inverter AC (Toshiba).

    • https://www.bijlibachao.com Abhishek Jain

      You can certainly keep AC at 30 degrees and there will be no harm and more energy savings.

    • Anand

      If we keep ac at 30 degree and outside temperature is 32 degree compressor will run for for more time bcz internal temperature is reached so fast.so compressor life decreased nu my ac mechanic told true ha boss

    • https://www.bijlibachao.com Abhishek Jain

      AC compressor should run for 9-10 mins for ideal running. It’s life will decrease if it runs for less than 3 mins.

    • Avadhut Das

      In an inverter ac (mine too is 1 ton inverter and I too keep at 30), where is the question of the compressor switching on and off? I thought in inverter acs compressors do not switch on and off, and instead run constantly at that lower power requirement level. Dear Abhishek, please correct my understanding.

    • https://www.bijlibachao.com Abhishek Jain

      Hi Avadhut,

      If your room temperature is 30 and the thermostat is set to 30, then even an inverter AC will switch off the compressor. That is the only situation in which inverter AC compressor will switch off. Otherwise it will not switch on and off if your thermostat is set to lower temperature than that of the room.

    • Shubham Das Gupta

      Thank you, Abhishek! :)

  • Life.As.I.Knew

    Dear Abhishek,

    First, Kudos to your continuous support in providing valuable suggestions.
    I have a unique Situation.
    Previous Year, i foolishly bought 1.5 ton bluestar ac(3hw18v) for my 10*10 room in middle floor (Chennai). Room is located in north direction (sun doesn’t directly fall). Point is.. room is getting cooled so fast, even at temperature setting of 27.
    What will be power consumption of the ac per hour? (1595 w. 2 ppl inside the room. Set temp – 28. Outside temp – 31.)
    Should i be worried about more power consumption, as the 1.5 ton is over-sized for my room? If yes, i m planning to sell this to my family member & buy a 1 ton ac.
    Is it ok to run the ac at 27-28C?
    we have a habit cycle of running the ac for 15 mins, turning off (with remote) for 20 mins and so on. is it ok(saving wise)?
    Which mode suits well for me? and less power consuming?

    Ravi Kiran

    • https://www.bijlibachao.com Abhishek Jain

      Your AC is certainly oversized and its compressor will cut off really quickly. You should try to measure the time for which the compressor runs before it turns of. For an Ideal AC, the compressor running time should be about 70-80%. So in an hour (60 mins), the compressor should run about 45 mins and should remain switched off for 15 mins (not in one stretch but overall). In one stretch the compressor should run at least 9 mins to achieve ideal efficiency. If it runs less than that, it is inefficient. In your case it would be starting and switching off very frequently. I think it would be better if you can give this AC to any family member and go for a 1 ton AC. Switching off is perfectly fine, but you cannot manage that at night. Best is to have a right sized AC. Try using sleep mode in the AC.

    • Life.As.I.Knew

      Appreciate taking your valuable time in answering to my query.
      I had tried to measure the time for which the compressor runs.. and it is approximately 10 mins after i turn it ON.
      What i’m lately doing is.. turning it on for 12-15 mins.. once the room cools down relatively i’m turning it off for 40 mins or so and turning ON again for 15 mins. Yes, at night it might be little tough… but still thats the temporary solution i’ve found (maybe i’m wrong). – Should i continue doing this.. atleast for this summer?
      Power consumption is 0.3-0.4 units for 15 mins. – Is it high or is it ok?
      In your previous comments you clearly mentioned that setting the temperature higher is recommended (less power).. but if i do so, i fear compressor will turn off quickly which ain’t good. So i’m setting it for 24-25.. whats your say?
      Is Cool mode better or Dry mode in my scenario – (oversized, chennai….power consumption)
      Running compressor such way… will there be any bad impact on the product/compressor??
      Yes, i should get rid of this 1.5 ton and go for 1 ton. But as we are already halfway this summer, somehow i want to manage/drag with this for this summer and go for new one next summer.
      Can i continue using this for next 1 month or so? If it will have bad impact on Compressor Operation.. then i will get rid of it righty away.. as per ur recomendation.

      Thanks a Ton in advance :)

    • https://www.bijlibachao.com Abhishek Jain

      Here are few points from my side:

      1) I think running it for 12-15 mins and switching off for 40 mins is perfectly fine. You just have to make sure that the compressor runs atleast for 3-4 mins (more is better). It is bad for compressor only if it switches off before 3-4 mins.

      2) 24-25 degrees is also perfectly fine. You can continue with that.

      3) 0.3-0.4 units per hour …. fantastic … nothing can beat that.

      4) Cool mode is better.

      5) No bad impact on compressor if it runs long enough as mentioned in point 1.

      There are automated timer switches available in market which you could have used to time it. But then if it is only for 1 month, so you may avoid that.

    • Rajagopalan Sv


      Mr.Life has said 0.3- 0.4 units for 15 minutes , that means 1.2 to 1.6 units per hour. It is not 0.3-0.4 units per hour. Is this consumption still okay?.

    • https://www.bijlibachao.com Abhishek Jain

      1.2 to 1.6 per hours is on a higher side.

    • Life.As.I.Knew

      Very valuable input. Thanks for the umpteenth time.

      In the previous reply you said the compressor should run for at least 9 mins.. and in the 2nd reply you wrote “atleast for 3-4 mins”.

      What’s the ideal run-time for compressor for long durability.
      No its not 0.3 to 0.4 units per hour. Its per 15 mins.

      If i had to choose buying a new ac, what would be your pick? (110 Sq.ft..Chennai..Sunny wall till 12pm & shady for rest of day)

      Carrier ESTER(3STAR) with Cooling Capacity of 3200
      Hitachi RAU312HWDS with Cooling Capacity of 3517 (higher the capacity, will it cool room faster & in case i move ac to big room, will it be effective compared to 1 ton less cooling capacity ac??)
      Hitachi RAU514HWDS 1.2 Ton ( i found this model to be effective, but again, will it be right buy (1.2 ton) for my room & situation)

      And i came across few models with Copper tubes but with Hydrophylic Aluminium fins (Voltas 123 Lyi). What are these fins? Should they be Copper too?(chennai). In Other models they don’t mention about the fins.. so by default were they copper?


    • https://www.bijlibachao.com Abhishek Jain

      AC compressor achieves ideal efficiency only after running for 9 mins. Less than that it would run at lesser efficiency.

      Life of an AC compressor decrease significantly if the compressor runs for less than 3 mins. Forget efficiency, it is just bad for compressor.

      For right sizing, I would suggest that you use the calculator on the page: https://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

      Also check FAQ no 13 on the same page for copper vs Aluminium.

  • Rajan thakur

    I have 2 tone capacity bluestar split ac for my 350 sqft hall. I set temperature at 29*and while room temperature at 31/32 whatever and it will take 5 min to reach at 29* at set temperature and compressor cutoff then again in 5 min compressor turn on ad it cool again till 29*
    So compressor running time 5 min and cutoff time 5 min aprox
    5 min on 5 min off duration so ut is perfect or enegy consuming

  • https://www.bijlibachao.com Abhishek Jain

    There is quite less that you can do if you are living in a rented place. All that you can do is putting up thick curtains on windows so that not much of sunlight comes in. See if you can paint the walls inside with an insulating paint or apply a thermal insulating wallpaper. Close the doors and windows tightly so that there is not much space for hot air to come in.

    As for thermostat, I am sure there must be a temperature setting in the AC. Increasing the temperature can actually help save electricity. So try keeping it to as high a number that makes you feel comfortable.

    • charleeCortes

      Thank yea I guess the place I live in has a lot to do with it it’s too hot here n the climate is well I explained that once lol well I try to set the temp as high as I can take it 26 celcius and it reaches that temp after 30 min then the compressor cuts off them after 4 min cuts on I guess there’s nothing I can do

  • SAP

    And will you clearly describe that what is auto mode function in AC??? is this best option to operating the AC?? and what is difference between auto mode and cool mode?

    • https://www.bijlibachao.com Abhishek Jain

      Esentially cool mode and auto mode are quite similar. The only difference is that in auto mode the AC tries to cool the room faster, which means that the compressor will run longer initially to cool the room quickly and then it will adjust the temperature to that set on the remote. But in cool mode, it will have regular operation and will cool normally till it reaches the set temperature. Cool mode is better.

  • SAP

    when i Set the temparature 25C in cool mode…the compressor is continuously running never shuts off untill completely shut down the Ac…during 2-3 hours it’s running…why????? is it goods or bad or any problem???

    • https://www.bijlibachao.com Abhishek Jain

      Well I guess either the heat load in the room is more than what the AC can handle or the AC needs some serious maintenance. A few things:

      1) I hope you are closing the room properly, I mean the doors and windows are closed such that there is no heat exchange from outside.
      2) I hope the AC is right sized and not undersized. An undersized AC will run all the time.
      3) I hope the room does not have too many people inside or too many things kept in.
      4) Make sure that the filters are clean and AC is cleaned regularly.

      The only thing that is bad with compressor running all the time is that it will consume a lot of electricity (if it is a non inverter AC).

    • SAP

      My room size is 13x14x10…and AC is 1.5TR..this is suitable for my room or it’s undersized??

    • https://www.bijlibachao.com Abhishek Jain

      There are multiple parameters required to calculate the right size. I would suggest that you use the calculator given on this link: https://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

    • SAP


    • https://www.bijlibachao.com Abhishek Jain

      1.5 ton AC should not be too bad for 182 sq ft room. However you may still check the right size using calculator on this page: https://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

      It may be slight undersized depending on the city you are in. Ideal running time of the AC should be about 70-80% of total time. Anything less than that is not good and more than that is not good.

    • SAP

      I am from WB bro…but you have been cleared my confusion…but one last question :P mera room to 182ft isliye 1.5 tr ac ke liye compressor ke upor kohi jyada pressure nahi padega to?????? undersized hone se problem kya hota hai???? sirf ghar cool hone me time lagta hai taki aur kuch???? electric consume ko lekor koi diggat nahi hai….device ka kuchh problem nahi hoga to???

    • https://www.bijlibachao.com Abhishek Jain

      Hi SAP,

      Undersizing an AC is always much better than oversizing. Very frequent stop starts are not good for ACs, whereas it is not bad if it runs continuously. But yes, undersized AC will take time to cool the room.

    • SAP

      Bro another one question… I have read a article about AC discussion in another website there said that for vey low temparature a pressure should be created on Compressor…and it may be harmfull for compressor…is it right??? can i set temparature for my new AC 20-22 degree???? please tell me the lower limit and upper limit for set temp. in AC??

    • https://www.bijlibachao.com Abhishek Jain

      Which website did you read it? I don’t think there will be any significant difference in pressure on the compressor at low thermostat temperatures. Pressure of gas is set when the AC is installed depending on the regular outdoor temperature in your city. If your city temperature is low, then the installation pressure would change. But then it does not have any relation with the temperature that you set on your AC.

    • SAP

      My room size is Length-14ft,Breadth-13,Height-10

  • charleeCortes

    Hi.. I have a few question!! #1 my window unit reaches 25C 10-12 min after compressor shuts off then it powers back on within 3-5 minutes i live in Honduras right now and the temp out side reaches to 100Fer.. so when the compressor shuts off it doesn’t take long for it to cut back on. So my question is, is that ok or should it stay off longer? #2 A few people told me the less the compressor shuts off and on the better because every time it cuts on and off it consumes more energy. Is that true? Also I have a mimi split in the living room so #3 is it better to cut the split completely off when im not home or put it on 29C so that the compressor wont cut on until I lower the temp? Im so lost with these units because im used to CENTRAL AC UNITS. :-( .. my units do come with a timer for start up time and cut off time as well. WHAT CAN I DO TO SAVE ENERGY

    • https://www.bijlibachao.com Abhishek Jain

      I would say two things:

      1) Ideal running time for an AC compressor is 9 mins, which is when it attains efficiency. But if it runs all the time, it will consume a lot of electricity, and AC compressors are meant to turn on and off.

      2) It should not have a very short cycle. I mean it should not turn off-on-off in less than 3 mins. If that happens, then it is bad for the compressor. But if it happens in 5 mins, that should be fine. But ideal time is 9 mins. AC compressor should run for 9-10 mins, then turn off, then again start after a few mins.

      3) It is always better to shut the AC down when you are not using it. That will save a lot of electricity.

    • charleeCortes

      See that’s were I get confused is it short cycling ? It stays running 10-13 min the shuts off for about 3-4 minutes then repeats I heard that’s bad yet I live in a hot humid country so I’m not sure I heard that the more it cycle back on it cost more I’m not sure anymore some say it’s better if it runs 20 min n cuts off 20 min but in these countries it’s so hot that it’ll reach heigh temps quick this making compressor cut on within 3-4 min

    • https://www.bijlibachao.com Abhishek Jain

      Shutting off for 3-4 mins is not too good, but also not something alarming. It is better if it shuts of a bit longer. Try decreasing the temperature on the thermostat and see how it goes. You may try some insulation for the room so that the temperature does not rise up quickly.

    • Arun Jagannathan

      Abhishek appreciate your patient replies … you say “shutting off for bit longer than 3-4 mins is good”. Surely in subsequent cycles, the Comp will run for under 10-13 mins at a time … but the Qs remains, Whats the ideal ratio of #1 Comp ON Vs OFF ? Is it 1:1 ? and #2 Duration of ON Vs OFF – is it like 5-6 mins ON and then 5-6 mins OFF ? Will it not consume more electricity if net net the Compressor is ON for longer than its OFF ?

    • https://www.bijlibachao.com Abhishek Jain

      Well there are two things:

      1) A delay of 3 minutes is required between two starts to equalize the pressure inside the system.

      2) When a compressor starts, it starts with low efficiency and reaches maximum efficiency when it runs for 9-10 mins. That is why it is better for AC compressor to run at least for 9-10 mins before shutting off.

      Typically while designing an AC, it is assumed that compressor will run 70-80% of the time in ideal state. Which means, in an hour the compressor should run roughly about 42-48 mins and should remain off for 12-18 mins. If we assume gap of 4 mins between two starts, it would be about running compressor for 15 mins then shutting it down for 4 mins then again running it for about 15 mins and then shutting down for 4 mins (initially when the room is hot it would run longer, this is for steady state). But then heat load in the room varies throughout the day and throughout the year. So it cannot remain the same always. That is why highly oversized AC are not just inefficient, they may not last long as well.

  • Syed Faheem

    Hi Abhishek,

    Appreciate your reply in my case.

    I run a library with 2 rooms equipped with AC, running for more than 12 hrs/day each.

    I set the temp mode to Auto or 24c but the students with their mobile apps change it 16 or 18c. Because of this, I am getting a big fat electricity bill every month.

    How do I fix this issue?

    • https://www.bijlibachao.com Abhishek Jain

      Hi Faheem,

      I don’t think there is an automated way to control it. You will have to stop the students from changing the temperature. How are they changing temperature using mobile app?

    • Syed Faheem

      Thanks for the reply Abhishek. There are many mobile apps like Universal Remote Control. Through that people can switch on/off the AC, change the temperature settings, etc.

      Is there any way I can manually fix the AC temperature to 24 or 25 so that even the remote or apps do not work?

    • sunny patel

      Set the temps. to 24 and then stick a black tape over the IR sensor of the AC

    • https://www.bijlibachao.com Abhishek Jain

      Hi Faheem,

      I am sorry, I am not aware of anything that can manually fix the temperature. The apps are based on IR sensor. If you disable IR sensor then the remote control of the AC itself will not work.

  • saumil

    Ideal temp range for ac is 24-26 so what if we keep it at 30??
    Please explain

    • https://www.bijlibachao.com Abhishek Jain

      If you feel comfortable, then you MUST keep it at 30, because you will save a lot of electricity if you do that.

    • GODDAMN Batman!!

      It will consume far less power.
      If the outside temperature is about 35, and you set the thermostat at 30, your AC just has to reduce the temp by 5 degrees. For reducing to 25, it would have to cool by 10 degrees. So less work consumed when set at 30.

    • saumil

      Thnk u

  • Jagdeep

    Hi abhishek my room size is 10*10 daily use is 8 hrs for 5 months . Which one is better in term of after sale service and durability. 1 voltas 125 CYE 1 ton 5 star . 2 Lloyd LS13A5Lx 1 ton

    • https://www.bijlibachao.com Abhishek Jain

      However, from energy efficiency or EER perspective Lloyd model that you have listed has EER of 3.63 while the voltas model has EER of 3.6. But the difference is too small. So there is not much difference from that side.

    • https://www.bijlibachao.com Abhishek Jain

      I would not say that Lloyd is a bad brand, but my personal preference would be for Voltas because I trust Tata group companies. And in general Voltas makes good ACs.

  • pankaj

    Hey Abhishek,
    Running AC on econy mode helps to save electricity can you please also elaborate what is econo mode if i run my ac on econy mode would it effect life of ac if i run it always on econy mode i have daikin inveter DTKP50 model

    • https://www.bijlibachao.com Abhishek Jain

      Hi Pankaj,

      The econo mode of Daikin is explained well on this link: http://www.daikinme.com/minisite/nexura/energy-efficient.jsp

      it just reduces the maximum operating current in econo mode. It is also explained well on this link: http://www.manualslib.com/manual/685027/Daikin-Ftxs30hvju.html?page=27

      All I can say is that typically an inverter AC, when it is started, runs at peak capacity (of 120%) to cool the room fast and then it stabilizes. But in econo mode, it will start at lesser capacity, take some more time to cool the room (it will not be fast), but will not consume more current in the begining.

  • Prajeet

    Does keeping the temperature setting of an 1.5ton airconditioner at 29 degree celsius really save units consumed vis-a-vis 25 degree celsius? Pls advise.

    • https://www.bijlibachao.com Abhishek Jain

      It will certainly save you a lot. To give you an example …. if outdoor temperature is 29 and you keep indoor at 29 …. the compressor will not work at all …. because there is no heat to remove to actually bring temperature down …. but then in the same situation if you keep it at 25 …. the compressor will have to work because it has to bring down the temperature by 4 degrees …… the amount of work a compressor does depends directly on the temperature difference it has to achieve.

  • Jigar Patel

    Hi abhishek
    I m Jigar Patel from surat, gujarat.
    I just buy Lyod 1.5 ton 3 star ac Ls19a3fx with power consumption 1572
    MY room size about 160 sq.ft. and on top floor
    Outer unit fixed at terrace, inner unit fixed on east wall of my room. South side most of wall of my room is covers glass slider wall with curtain.
    Is my ac is enough for that situation.?
    What is best operating mode to run at night?

    • https://www.bijlibachao.com Abhishek Jain

      Hi Jigar,

      My guess is that 1.5 ton AC is slight undersized for your room, especially during the day time. At night it should be sufficient. Also if you keep the outdoor unit on top of the terrace, direct sunlight will reduce its effectiveness. So all in all, during the day it will be less effective. At night it should be fine.

      As for best mode of operation, it depends on what is comfortable for you. Try to keep the temperature as high as is comfortable to save electricity. Because your ceiling is directly facing sun during the day, using ceiling fan may not be very effective. Try to use it in sleep mode or economy (energy saver) mode.

  • Soumen Sadhukhan

    Hi Abhishek da

    I perches 1.5 ton lloyd 3star ac(LS19A3DX). If i run this ac regular 5hr per day. which amount of bill i aspect end of the month ?

    • https://www.bijlibachao.com Abhishek Jain

      Hi Soumen,

      A BEE 3 star rated 1.5 ton AC should add about 1.3 units per hour of running. So in 5 hours it would consume 6-7 units per day.

    • Soumen Sadhukhan

      Thanks abhishek da….. :)

    • Soumen Sadhukhan

      LS19A3DX model is good? what you think?

    • https://www.bijlibachao.com Abhishek Jain

      Lloyd is a decent brand and this is BEE 3 star rated model. No reason to say anything bad about it.

  • mukti nath

    I brought whirlpool 3dhool hd 1.5 tn 3 star ac. Day time it cconsuming more then 3 unit in 1 hour.is it ok.

    • https://www.bijlibachao.com Abhishek Jain

      3 units in 1 hour is bad.

  • rafeeq

    Hi abhishek

    I recently bought an o general 2 ton ac.which consumes about 2.5 units per hour .is it normal or not.please suggest me method which I can reduce the power consumption
    By the way I set the ideal temp also 25°c it won’t works .

    • Deepak

      Just see the wattage of your AC. My AC is 1 ton and has power wattage of 1032 watts. It means it will consume 1.032 units in 1 hour. 1 unit is 1000 kilo watt hour.

    • https://www.bijlibachao.com Abhishek Jain

      It does not work as straightforward as that unfortunately.

      AC has several components: Compressor, Fan, other electronics. The power consumption mentioned on the AC is sum of peak power consumption of all these components. But then compressor goes on/off (in case of non inverter AC) or reduces speed (in case of inverter AC). Even the fan speed varies and the consumption of fan varies with that.

      So it does not consume 1032 watts for the full time.

    • https://www.bijlibachao.com Abhishek Jain

      2.5 units per hour is quite on a higher side. My guess is that the AC is not very energy efficient. You may try some of the insulation techniques given on this website: https://www.bijlibachao.com/save-electricity/insulation

    • rafeeq

      Its wattage is 2480

    • rafeeq

      Yeah it’s right the EER is 2.91.

    • https://www.bijlibachao.com Abhishek Jain

      EER of 2.91 is really low. It would consume lot of electricity.

  • Naresh Kumar

    Hi Abhishesk

    I have recently purchased 1.5 LG Split ac model number LSA5AT3D1. I live in chennai on top floor and outdoor unit is installed on terras of my building. Room is completely closed and i am asking this as its been more than 3 hours ac is running and its not going lower than 24c (in night time)

    also i have seen that in remote provided by LG that my room temperature never touches lower than 24C even if set to 22 room size is 12.5*10 Feet.

    Hope to hear solution from you.

    • https://www.bijlibachao.com Abhishek Jain

      Hello Mr Naresh Kumar,

      1.5 ton is the right sized AC for your room. It should certainly cool the room. How are you measuring the temperature of the room? It could be possible that the AC was not installed properly and it does not have sufficient gas pressure in it. Would suggest you to call a technician from LG to check the same.

    • Naresh Kumar

      Thanks for your reply Abhishek. Iam measuring the temperature of the room through LG AC remote. I have called technician from LG and checked the Gas pressure. It was 65 PSI. My doubt whether room temperature will reach equal to set temperature of AC or not and Remote is showing correct room temperature or not?

    • https://www.bijlibachao.com Abhishek Jain

      65 PSI is on the lower side. If the outside temperature goes to 45 degrees then ideal PSI for R22 is 75 (Source: http://www.advantageengineering.com/fyi/289/advantageFYI289.php ). That could be one reason.

  • Mike

    Hi Abhishek,

    For compressor to be ON/OFF at regular interval based on the settings i.e. temperature @ 25. Does it have a side effect on the compressor?

    When AC is switched ON from the remote, the outdoor unit start operation faster within 5-10 secs. Is this normal for an AC? The brand is LG.

    Hope to hear from you.

    • Mike

      Thanks for your reply, but i need clarification on this:

      1. when there is power failure it takes 3-4 minutes for the outdoor unit to start operation when power is restored.

      2. In case it was powered OFF then ON from the remote control it takes lesser time for the outdoor unit to start operation i.e. 5-10 seconds.

      What is the cause of the (2) time difference (power failure/remote control)?

      Kindly assist,

    • https://www.bijlibachao.com Abhishek Jain

      Hi Mike,

      ACs have a time delay system to prevent it from “Short Cycling” or frequent on/off. Ideal running time of an AC compressor is about 9-10 mins to attain peak efficiency. If the AC is oversized then this time goes down to say 3-4 mins as well. But then anything lower than that is surely detrimental for the AC compressor. And that is why a time delay is put in an AC to make sure that the AC does not short cycle in case of voltage fluctuation or power cuts. Not sure why it is not happening with remote control. It should happen for that as well.

    • https://www.bijlibachao.com Abhishek Jain

      ON/OFF based fixed speed compressor does have lower efficiency due to ON/OFF, but then they are designed to work like that for 10-15 years. ACs for years have been working like that (only recently we have got inverter tech which does not gets on/off). And ACs have been working for 10-15 years for people.

      I do not see any anomaly in your AC.

  • Imtiyaaz

    Hi Abhishek Bhai,

    Thanks for being here, Your replies helped a lot in understanding measure to save electricity. I have few doubts with my New and first LG Smart Inverter AC Operation. LG Care was not able to answer my queries and i am left alone… Pls do help me in understanding..

    I set temp @ 28 and ran AC in Auto Mode. The AC is turning off even after reaching room temperature of 25. I dont know whether there is a set temp in automode or i have to set temp.

    I tried cooling mode again, the room temp reached 26 yet the outdoor unit is giving sound which means the compressor is running. So how will this autoshut works.

    Pls let me know one way of using ac in economy mode. Last night i set 28C and in auto mode for three hours it consumed around 4 – 5 units. I am afraid being a middle class.

    And last one when to use fan mode… I know these are silly and annoying questions but still i request you to share your wisdom so that i can save few units of electricity.

    Thanks in advance

    Dr Imtiyaaz

    • https://www.bijlibachao.com Abhishek Jain

      Imtiyaaz Bhai,

      Fan mode is one in which compressor does not work. It is just the fan that works.

      As you have an inverter AC, it should not turn off after reaching the desired temperature. A regular fixed speed AC has on-off of compressor because it cannot vary its speed based on the cooling requirement. And that is where inverter ACs bring in efficiency as they do not turn off when the desired temperature is attained. It just slows down its speed. So sound would be more when compressor is running at a faster rate and less when it is running at a slower rate. But it should not shut down.

      It can shut down compressor only when outside temperature is 28 and you have set the temperature in indoor unit to 28. In that case there is nothing for the AC to do as the temperature outside and inside is the same and there is no heat to remove.

      But 4-5 min in 3 hours is a lot for inverter tech AC!! Did you keep the room open? Do not leave any doors or windows open when using AC. Also do you get direct sunlight on the room ceiling or walls during the day? In such cases getting a white roof or white wall can help you reduce electricity consumption.

    • Imtiyaaz

      Forgot to tel you about MY AC

      Its for 110sq feet room One ton LG Smart Dual Inverter 4star rating ac BSA12BEYD with 1050 watts.

      Will wait for your response bhai…

    • https://www.bijlibachao.com Abhishek Jain

      This should not consume 4-5 units in 3 hours. Something is wrong somewhere.

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  • pankaj

    Hey Abhishesk

    I have recently purchased 1.5 daikin inverter ac model number DTKP50 i live in delhi on top floor i would like to know how much time does it take for the temperature to reach at 22 C if outside temperature is 42-44 . room is completely closed and best curtains are put inside the room i am asking this as its been more than 2 hours ac is running and its not going lower than 25 (in day time)

    also i have seen that my room temperature never touches lower than 25C even if set to 22 room is quite bigger in size which is 12.5*16.5


    • pankaj

      Dear Abhishek,
      Waiting for your reply

    • https://www.bijlibachao.com Abhishek Jain

      Hi Pankaj,

      Firstly I would suggest that you check the calculator on this page to check if the size of the AC is right or not: https://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

      An undersized AC will take a whole lot of time to cool the room. And sometimes it may not even cool to the desired temperature. Secondly it is also possible that the outdoor unit is directly facing the sun and thus is not able to work efficiently. Time taken to cool will depend on outside temperature, cooling capacity, heat load in the room ,etc.

    • pankaj

      Dear Abhishek,

      Thanks for the your reply.Can you suggest how can i protect outdoor unit from direct sun any cover or protector is available in the market also i would like to know since i live on the top floor thus fan put on ceiling make it more hot is it good to put a tower fan along with ac

    • https://www.bijlibachao.com Abhishek Jain

      First thing that I feel is that your AC is undersized. That could be one major reason for undercooling.

      As for protector: there is none that I know of. You can try putting plant around it so that they can keep the environment cool. But basically there should be less heat around the outdoor unit to help it throw hot air outside.

    • pankaj

      Thanks Abhishek i called service engineer he did something now it takes 30-45 mins to reach at 25 C however i dont use fan it takes 5-6 unit(max) when i set it to 25C and i On it at 11 night and off it to 8:30 in the morning this 5-6 units include my fridge running for whole night and TV for 1 or 2 hour do you think its good consumption

      putting a tower fan with ac is a good idea please give ur opinion

    • https://www.bijlibachao.com Abhishek Jain

      Daikin FTKP should consume about 0.7 units per hour (max). Which means in 9.5 hrs it should consume max 6.6 units. It is consuming much less than that (as heat load is low at night). Which I think is good. Because your fridge would also have consumed about a unit by that time. So Fridge + TV would be 1.2 units or so (max).

      I think it is consuming the right amount of electricity. You can certainly put tower fan if it helps you to increase the temperature from 25 to 26 or 27 without loosing comfort. If you still keep it at 25 with fan, then it does not help. It helps only if you are able to increase temperature of the AC.

    • pankaj

      Also it shows temperature of 24-23 sometime even if i have set it to 25 is it to worry about or this is normal behavior

    • https://www.bijlibachao.com Abhishek Jain

      It tries to stabilizer, but slight up or down should be fine. 24 sounds fine, but 23 is a bit more. But as long as you are comfortable, I do not think you should worry.

    • pankaj

      Thanks Abhishek

  • Dhruba Dutta

    Hi Abhishek,
    I have Daikin inverter 1ton ac for my room which is around 140sqft. And my outdoor unit installed two floor above my room due to lack of provision.
    Now the ac is not reaching 25degree temp even after it is running for 1 hour, when room temp is around 35 degree.

    So what could be the issue and how to solve that?
    Please suggest.

    Dhruba Dutta

  • Bhoboghure Jhor


    I’m having a problem with my AC. O general 1.5 ton in 110 sqft room. My outdoor unit turns on 3 mins after first start if it is left for 1 day without run. But if I run it in regular interval then it takes 20-30 secs.
    Is it OK?
    Another thing is that now temp outside is 34-35 degree with humidity 55-60%
    Its taking 25-30 mins to make temp 25 degree. 1 hour to make 23.
    2 hours to make 20 in day time.
    Is it OK?
    Once you have told me a good AC should take 10 mins to make 25 degree…my AC is new….should I call for an engineer?


    • https://www.bijlibachao.com Abhishek Jain

      Oversized Ac should not take much time to cool. You should call an engineer.

  • Waruna

    Can you point me to a good energy meter to check the power consumption of my AC preferably from ebay?

  • http://www.wrock.org Sandeep Tanwar

    Hi Abhishek,

    Your website is very informative I have decided my specification but not able to decide which brand to choose from please suggest any brand name.
    I need 1.5 ton, Some my friends suggests me to go for O-general or Diekin
    So does it really matters if I go for other brands like LG, Whirlphool, Bluestar else any other because O-General ac are very expensive does they worth that price compare to low price brand in any way. And which brand you are using?

    I’m from Haryana and In summers some times temperature goes more than 45C. Please name any brand AC because now I don’t want to hear to choose myself and these all are best please name it.

    waiting for reply

    • https://www.bijlibachao.com Abhishek Jain

      Hi Sandeep,

      While buying an AC, the first and most important thing to know is the right size or tonnage of AC to buy (which depends on the size of the room, etc). The next thing is to understand the right star rating (which depends on your usage of AC in hrs/year). Technology/brand etc are the 3rd important factors. I would suggest that you use the calculator and FAQs and the list of top efficient ACs given above on this page to evaluate the right thing. Once you have done that and you still have doubts, we will be happy to answer them.

      Also please do check this page where we have given our opinion on various brands: https://www.bijlibachao.com/general-tips/brand-analysis-which-is-the-best-brand-to-buy.html

    • http://www.wrock.org Sandeep Tanwar

      Actually this is not what i’m asking. They are just opinion but you haven’t give any recommendation that I should go for.
      Which AC should I choose Voltas vs LG vs Whirlpool vs Hitachi under 35k budget spit ac

    • https://www.bijlibachao.com Abhishek Jain

      From what we have in our database, these are the most energy efficient models from your selected brands in 35K budget:

      Whirlpool 3D COOL PLT V (1.5 T)
      Voltas 185 JY
      Voltas 185 DYI
      Voltas 185 EY(S)
      Voltas 185 CYA

      Their details are in the image attached. You can also check our database on this page: https://www.bijlibachao.com/research/list-air-conditioners-available-indian-market.html

  • Barathi Raja Kirubanandham

    Hi Abhishek,

    I recently purchased Bluestar 1.5 Ton Split Ac for my 120 Sq.ft room whose roof gets direct sunlight.
    Suggest me best the mode of operation during nights. I live in Chennai.
    1. Running the AC in Auto mode full night. ( I’m afraid of power consumption in this method).
    2. Keeping in cool mode and switching the AC off and on in an interval of one or two hours (which disrupts the sleep).

    Thanks in advance for your suggestion.

    • https://www.bijlibachao.com Abhishek Jain

      Minimum temperature that you should keep should be 25 degrees.If you can keep more (like 26-27) then it will be better.

      If you have energy saving mode in the AC then use that. It will automatically switch off the AC periodically.

      Try using sleep mode (if there is one). Sleep mode increases the temperature by a degree every hour or two. This helps in saving electricity.

      You can also consider finding timer switches in market that can be programmed to switch on and off AC periodically.

  • ajay

    Hello Abhishek,

    I have purchased 1.5T Inverter A.C. of Lloyed company. I am living in trivandrum where max. temp. varies from 33 to 35 degree.
    Which will consume less electricity; using AC continuously for longer hour by setting the temperature 28 or 29 degree with fan( which i am doing and i am comfortable in it) or setting the temperature 25 degree or lesser for shorter time and when room gets chilled, we can off it. Please tell me.
    with thanks

    • https://www.bijlibachao.com Abhishek Jain

      Your current usage of 28-29 with fan will give you most energy saving. However I just hope your ceiling does not get direct sunlight. If it does then better avoid using fan. But if it does not, then your current mode is the best.

  • Bhoboghure Jhor

    Dear Mr. Abhishek Jain

    I have a question….I have discussed about my AC performance with you earlier….my OGeneral 1.5ton ASGA18AHT 1 star AC requires 35 mins to cool my 110 sqft room (undersized for AC) up to 21degree….and 1 hour to make 19 degree when it is 30 degree outside…..As you have said the time is OK….but one of my relative have 1.5 ton Jadroo AC in his 160 sqft room it takes 40 mins to make 21 degree….seems faster than my one….but my one is brand new and of good brand….location and other factors are almost same….one thing I noticed is that…..my outdoor is placed in a balcony where the opposite wall is only 3 ft away from my outdoor units fan….so a considerable amount of hot air bounces back to unit….is it causing the slowness in performance…what should be the ideal distance to make it working perfectly?
    Thanks in advance…..

    • https://www.bijlibachao.com Abhishek Jain


      Heat on the outdoor unit can impact the cooling of the AC. It could be the reason why it is not cooling quickly. I would suggest that you call service engineer from General and get it checked.


  • firoz basha

    Hi sir we bought a new lg air conditioner with mosquito away technology 1.5 ton and 5 star rating our room temparature is not getting below 25 even i gave the input to 18 . What might be the reason for it??

    • https://www.bijlibachao.com Abhishek Jain

      A right sized AC should be able to get your room temperature to 25 quickly, but 18 is really really low and it will take quite some time to get it down to 18. However 25 is quite cold and comfortable. You will have to leave it on for more than an hour to get it down below 25 and 18 will take really long time. You will have to significantly oversize the AC (as per the requirement of your room) to get it to 18 really quickly.

  • prk

    Hi sir, I am buying a new AC, I don’t know exact dimensions of my bedroom, but it is a bedroom in normal 2 BHK homes. Some people in my building have 1 Ton AC. Will it be better if I go for a 1.2 ton 5 star AC (Voltas 155 CY) at Rs.25800 instead of 1Ton 3star AC as the price is almost same for good brand. I guess the power consumption will be similar for both. Please tell me is it okay and am I right ? Thank you.

    • https://www.bijlibachao.com Abhishek Jain


      Oversized ACs consume more electricity and thus right sizing or slight undersizing is always good as far as electricity consumption is concerned. I cannot comment on which size would be good without knowing the size of the room and the city where you live and your usage. Would suggest you to use the calculator given on this page: http://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

    • prk

      Sir I tried using the calculator, your calculator shows 1 Ton 3 Star will consume 0.86 units/hour for my approx room size, if I increase room size by 1 feet in length it shows 1.2 Ton AC required and 5 Star variant of 1.2 ton will consume 0.85 units/hour. And I was getting 1.2 Ton 5 Star at same price of 1 Ton 3 Star, so I guess 1.2 Ton 5 Star is more economical for me. Please suggest and thanks for previous comment.

    • https://www.bijlibachao.com Abhishek Jain

      Hi prk,

      The numbers in the calculator are just representative numbers. Power consumption varies from model to model and even star rating is a range of power consumption i.e. not every BEE 3 star rated AC consumes the same amount of electricity. And a range of power consumption numbers are given a star rating. What we have taken is the median number or the power consumption number that is most likely for a BEE 3 star rated AC (it can be more or less).

      Also an oversized AC is slightly more inefficient than a right sized AC. If your room size is more than what you have used for calculation then 1.2 ton 5 star would be good.

    • prk

      Thank you. I will think and decide final.

    • prk

      @abhijain203:disqus sir please reply

    • https://www.bijlibachao.com Abhishek Jain

      Sir, had a family emergency to attend to, so could not reply. Please accept my apologies.

    • prk

      sir why are you apologizing , I understand that there might be some problem. Please reply to my comment to your reply above this. Thank you very much. Your website is a boon for many like us.

  • Sunny

    Hi Abhisekh,

    Can you please share the review of Voltas 183 SY model 3 star? I am planing to buy this. Also, if you can let me know any other brand in the price range of 30K – 32K? Thank you

    • https://www.bijlibachao.com Abhishek Jain

      Hi Sunny,

      I would strongly suggest that you look at Calculator, FAQ and list of top ACs on this link on our website: http://www.bijlibachao.com/top-ten-appliances/best-air-conditioner-ac-window-split-hitachi-lg-carrier-samsung-electricity-consumption-tonnage-in-india.html

      It will help you choose the right size, right star rating and right model/brand of AC for your room.

    • Sunny

      Hi Abhisekh, thanks a ton, i finally bought Voltas 183SY model. I live in a remote location in Gujarat where temperature soars upto 38-39 in march and April and can increase upto 42 degree in May and June. What i have observed recently is when i start the Ac on a cool mode or saver mode, it takes around 30-40 seconds for condenser to start, till then only fan is working. Once the condenser starts then it works as expected. Is it normal or there is problem which is delaying the condenser to start? Thank you

    • shubham

      i bought the same model ac, I’d like to know whether they did air purging thorugh vacuum or not? and also, im not able to reach a temp lower than 24c(outside temp 43c). please reply

    • https://www.bijlibachao.com Abhishek Jain

      For R22 the gas pressure should be about 75psi.

    • https://www.bijlibachao.com Abhishek Jain

      They should vacuum the pipes while installing. Another reason could be low gas pressure for it to not cool well.

    • https://www.bijlibachao.com Abhishek Jain

      Some “time delay” is needed for the compressor, but 30-40 seconds is really long. Should not take that much time if the fan has started working.

  • Nishi

    My outdoor unit is directed toward the sunlight as i stay on top floor. Due to which my room is like hell hot. Do I cover the outdoor unit with something or what should I do as there is no way to move it anywhere else, please help :(

    • https://www.bijlibachao.com Abhishek Jain

      Try putting some cover or putting some plants around it. If that does not work well then you may have to shift the outdoor unit to a place where there is less heat.

  • Ratul

    Hey Man… There is a problem i am facing for a while now, I got a sharp AC and it stinks. The AC is 1.5 ton and the room size is decently big, as in my AC size is in parity with the room size. I usually run the AC at 28. it works fine for me. The technician says i need to run it at lower temperatures or it will stink. Is it true? Please help!!

    • https://www.bijlibachao.com Abhishek Jain

      ACs typically stink when they are short cycled i.e. their compressor runs for very short time and there is lot of humidity. In shorter cycles it is not able to remove humidity properly and it does stink in such cases. This typically happens when AC is oversized for a room. You have mentioned that it is a Sharp AC, is it an inverter technology AC (as sharp mostly has inverter ACs)?

      Which city are you from and what is the room size? It is possible that the AC is getting short cycled at 28 and may get better if you decrease the temperature (as compressor would have to run longer).

  • Waruna

    Do you save any money by going with new LG Inverter V AC
    with Active Energy control where LG claims you can cap the compressor speed to
    40%, 60%, and 80% of total capacity? If you cap the compressor speed to say at 40%,
    it would take longer to achieve the desired temperature but it will take less
    electricity compared to running the inverter on AC on full capacity. But if you run
    the AC at full capacity, it will take less time to achieve the desired temperature
    and the compressor would dial back on its own when it achieve the target temperature in
    less time compared to running it at 40% of capacity thereby reducing energy consumption
    since its only running for a shorter period with high capacity. Given this
    situation, do you think Active Energy control actually saves electricity by
    capping the compressor speed or you think this might only work when the heat
    gain is minimal such as using the AC at night? I can however see this might help to reduce humidity with longer run times at reduced capacity.

  • Mihir

    I took daikin 1 ton ac before 1 week and my room size is 120 sq ft when i keep at 22° the compressor gets cut off in 8 to 9 min is this normal??

    • waes

      Does it take 8 -9 mins to reduce temp to 22 degree from its first run????
      Or after considerable cooling ???

      I got a General 1.5 ton in 110 sqft room. Takes 25-28 mins to make 22 degree….then it runs 3-4 mins in every 12-13 mins….is it normal????

    • https://www.bijlibachao.com Abhishek Jain

      Depends a lot on the heat load of the room and the cooling capacity of the AC. Heat load of the room depends on size of the room, temperature outside, things kept in the room, insulation of the room, appliances used in the room, etc.

    • Bhoboghure Jhor

      Brother one more thing….I’m having a new AC (General 1.5 ton ASGA18AHT with admiral compressor)….since my installation I am suspecting that my AC is not cooling as efficiently as it should be…In my 110 sqft room (undersized for AC)….it should take only a few mins to cool….it takes around 30 mins from start to make it cool….then compreessor runs for 4 mins in every 12-13 mins to maintain 22degree….I am not a pro…how can I be sure my AC is not running low in refriegerant??…Is there any way to check manually…. Both of my outdoor units copper pipe sweats while in operation…thick one gets colder than thin one and sweats more….is it OK?….my outdoor unit is placed in my balcony….but in a bit congested place….is it why its taking much more time to cool???….or my cooling time is OK….refrigerant is R22….it takes around 1 hour to make 18 degree….thanks in advance for your valuable opinion

    • https://www.bijlibachao.com Abhishek Jain


      Are you using a thermometer to check temperature of the room? Ideally a right sized AC is one which should bring the room temperature to 25 degrees in 5-10 min. Going down to 22 will take further more time and 18 would be really long. From what you have written, the cooling time looks fine to me. In fact as you rightly said, it is oversized. A right sized one will take further more to go down to 22 if you really measure using a thermometer. And there after 9 mins should be ideal cycle time. In your case it is 4 min as it is oversized. 25 is a good temperature, 22 is really cold. To me it looks fine.

    • https://www.bijlibachao.com Abhishek Jain

      8 to 9 mins of compressor run is ideal. It means the sizing of the AC is good. If it cuts off in lesser time then it is oversized. If it runs much longer then it is undersized.

  • Waruna

    Is it okay to oversize on an inverter ac for a room that’s
    14x19x12 than undersize to save on electricity provided you are indifferent about
    upfront cost? If you oversize, say with a 2 ton inverter, unit will decide on its
    own what’s the best tonnage requirements to cool them room thereby using
    minimal power and electricity to achieve and maintain the temperature compared
    to an undersized or right size unit?

    • https://www.bijlibachao.com Abhishek Jain

      Slight oversizing in inverter ACs is fine but not too much oversizing. All inverter ACs have a lower value of cooling capacity as well. A 2 ton inverter AC would have a range of 0.8 to 2.2 ton, but if your room needs 0.75 tons cooling then a 2 ton inverter AC would be a waste. However a 1 or 1.2 ton would still be good.

    • Waruna

      Forgot to mention. it will only for night use

  • Subhasis Biswas

    Sir, do you stay up all night?

    • https://www.bijlibachao.com Abhishek Jain

      Not at all :). Only till midnight if there is work :).

  • Gsn

    Hi. Please suggest whether Inverter based ac is suitable for cities with very high temperature like Nagpur?
    Max temperature here reaches 48-49 deg in peak summers. The demo guy in electronics shop suggested us not to go with inverter based ac and buy 5star rating ac instead..in Nagpur.

    • https://www.bijlibachao.com Abhishek Jain

      There is no truth in that statement. Inverter ACs work equally good across the world. 100% of Japanese market and more than 50% of European market uses Inverter Technology. And Inverter ACs have worked fantastic in India in last 5 years which is why their penetration is increasing.

  • Subhasis Biswas

    Hitachi kashikoi 300i 2 ton, is this a good ac? I can get one for about Rs. 62000

    • https://www.bijlibachao.com Abhishek Jain

      Hitachi Kashikoi models are really good ACs. You should certainly go for it.

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  • Guest

    Quote: “If you set the thermostat at 18oC (64.5oF), does it mean that the air conditioner will cool the room faster than if set at 25oC (77oF)? No”

    Actually, the correct answer is Yes for Inverter AC, which are becoming more popular for their energy efficiency and ability to cool/heat quicker, than non-inverter ACs. Also, they provide better temperature accuracy.