Aircon Energy Saving Tips That Lower the Bill

The tips fall into three groups: stop heat getting in, set the unit sensibly, and keep it clean. The last one is partly ours. An aircon cleaning visit washes the filter, the blower and the indoor coil and clears the drain. A clean filter and coil let the unit cool the room in fewer hours.

Keep the heat out of the room

Every bit of heat that gets into the room is heat the aircon has to take out again. Meralco’s advice is to close doors and windows while the unit runs and to block the sun with curtains or blinds. Hitachi says to keep the blinds closed through the hottest part of the day. These are the ways in:

1. 1The roof. A room right under it gains heat all afternoon. Insulation above the ceiling cuts how much comes through, and the room may need a bigger unit.
2. 2The sunny window. Keep the curtains or blinds closed through the hottest part of the day.
3. 3The door and the gaps. Keep doors and windows shut while it runs, and seal the gaps round a window type unit.
4. 4The TV and the lamps. Keep them away from the indoor unit. Its thermostat senses their heat and keeps it running longer.
5. 5The outdoor unit. Shade it, but leave space around it so the air can get through its fins.
6. 6The setting. 24 or 25 degrees. A lower number does not cool the room any faster.

Hitachi and LG Philippines both say to seal gaps. For a window type unit, the ENERGY STAR advice published by Natural Resources Canada is to close the large gaps with the side panels or curtains the maker supplies, then stop the remaining cracks with peelable caulking. Hitachi adds the heat you make yourself: use the oven and the stove at cooler times of the day where you can. Meralco says to keep lamps and TVs away from the indoor unit, because its thermostat senses their heat and keeps the unit running longer than it needs to.

A room right under the roof gains heat all afternoon. Hitachi names insulation as the way to cut how much comes through, and a room like that may need a bigger unit than its floor area suggests. The aircon size by room guide works out how much bigger.

Set it at 24 or 25 degrees

Meralco calls 24 or 25 degrees a comfortable setting, and the Department of Energy’s ENERTIPS sheet recommends 24. Meralco adds that setting a colder number when you switch on does not cool the room any faster. The lower number only moves the point where the unit eases off, so the compressor keeps going after the room is already cool. The best temperature for aircon guide explains why the setting works as a stopping point.

A fan helps. Hitachi says a ceiling fan in the room you are using lets you keep the setting a little higher and still feel comfortable.

Fan speed and dry mode on humid days

Meralco’s rule is to run the fan on high as a rule, and on low on very humid days. Slower air spends longer passing the cold coil, so more moisture comes out of it and the room feels better at the same setting. LG Philippines makes the same case for dry mode: when the air indoors is humid, dry mode lowers the humidity so the room feels comfortable at the same temperature, and LG calls that more efficient than a more energy-intensive cooling mode. The dry mode guide covers when to use it.

Use the timer, and switch it off when the room is empty

Meralco says not to leave the unit running all night: set the timer to switch it off after a few hours or once the room has cooled. The Department of Energy’s sheet says to switch it off, or unplug it, when it is not in use. Most bedroom units have a sleep or off timer on the remote; the aircon remote symbols guide shows which button it is.

Keep the filter and the coils clean

The filter is the part you can clean yourself. Meralco says to clean filters at least once every two weeks, especially in the months the unit works hardest, and LG Philippines says to check it every two weeks. Meralco also gives a test you can do in a minute: hold the filter up to the light, and if you cannot see through it, it needs cleaning. A dirty filter blocks the airflow, and the unit runs longer for the same cool.

The coils behind it need a technician. The Department of Energy says to clean the filter and vacuum the outdoor coil regularly, and Meralco suggests a professional clean and check every quarter. An aircon cleaning visit covers the indoor side. An aircon maintenance visit adds the outdoor coil and a check of the gas level. The aircon cleaning schedule sets out how often each one is due for how hard your unit works.

Give the outdoor unit shade and air

The outdoor unit gets rid of the heat taken out of the room, and it does that worse in the sun. Meralco says to shade it but not to block its airflow. The Department of Energy’s sheet says the same of where the unit goes: on a shady side, where the air can circulate. So nothing should press against its fins or box it in. If you are putting in a new unit, the placement is decided at the aircon installation.

Signs the unit itself is wasting power

The bill goes up while you use it the same way.

Hitachi puts this first among the signs a unit is wasting energy.

It runs longer than it used to before it reaches the setting.

Hitachi lists the usual causes: a clogged filter, a dirty coil, low refrigerant from a leak, or a unit the wrong size for the room.

One part of the room stays warm.

Uneven cooling is the third sign Hitachi names.

A clean filter is the first thing to try. If the unit still runs long, it needs an aircon check-up. Low gas always means a leak somewhere, and topping it up without finding the leak only puts off the next refill; the what is freon guide explains why. The common aircon problems guide sorts the other symptoms.

The right size, and an inverter for long hours

Meralco puts the case against the wrong size both ways. A unit too big for the room switches on and off more often and uses more energy doing it. A unit too small never stops running, because it cannot reach the setting. The aircon size by room guide and the aircon HP calculator find the size that fits.

How many hours a day the unit runs decides the type. Meralco says an inverter gives meaningful savings in a room where the aircon runs for long hours. The inverter vs non-inverter running cost guide sets the kilowatt hours side by side at 2, 4, 8 and 12 hours a day.

How to read the energy label

Room aircons sold in the Philippines must carry the Department of Energy’s energy label. Under Section 15 of the Energy Efficiency and Conservation Act, Republic Act 11285, the label shows at the minimum the unit’s efficiency rating, its monthly energy use at a set number of hours a day, the brand and model, and the year the rating was issued. DOE’s own list of labelled units also gives each one’s cooling capacity in kilowatts, its CSPF, and a rating from 1 to 5 stars.

1. 1Brand and model. Check it matches the box, so the label is for the unit you are buying.
2. 2Cooling capacity. Match it to the room first. If no unit matches exactly, Meralco says to take the next one up.
3. 3Stars, 1 to 5. The efficiency rating. More stars is more efficient. Compare it only between units of the same capacity.
4. 4CSPF. The efficiency figure. A higher CSPF means more cooling for each kWh.
5. 5kWh a month. Worked out at a set number of hours a day, so it compares two units fairly. Your own bill follows your own hours.
6. 6Year rated. When the rating was issued.

The spread between units of the same size is wide. On DOE’s list of active labels at 30 June 2026, two wall-mounted split types are both sold as 1.0 HP. One, with 2.78 kW of cooling, is labelled 43.35 kWh a month, a CSPF of 7.04 and 5 stars. The other, with 2.64 kW, is labelled 79.65 kWh a month, a CSPF of 3.95 and 1 star. That is nearly twice the energy for a unit sold as the same size, with a little less cooling.

So compare like with like. Meralco’s rule is that between units of the same cooling capacity, the more efficient one costs less to run. Find the capacity your room needs first, then pick the label with the higher CSPF and the lower monthly kWh. Your own bill will not match the label, because your hours are your own; the aircon running cost calculator works it out for the hours you actually use.

Questions people ask

What aircon temperature saves the most electricity?

The highest setting you are comfortable at. Meralco calls 24 or 25 degrees comfortable, and the Department of Energy recommends 24. A colder number does not cool the room any faster. It only moves the point where the unit eases off, so it keeps cooling long after you were comfortable.

Does cleaning the aircon lower the electric bill?

Yes. Meralco says a dirty filter blocks the airflow and cuts the unit’s efficiency, and Hitachi lists clogged filters and dirty coils among the reasons a unit runs longer than it should. Wash the filter at least every two weeks, especially in the months you use it most. Meralco also suggests a professional clean and check every quarter; the cleaning schedule guide sets the gap by how hard your unit works.

Does dry mode save electricity?

On a humid day, it can. LG Philippines says dry mode lowers the humidity so the room feels comfortable at the same temperature, and that this is more efficient than a more energy-intensive cooling mode. This site’s dry mode guide keeps it for air that feels sticky but not very hot.

What do the stars on an aircon energy label mean?

They are the efficiency rating, from 1 to 5. The Department of Energy’s list of labelled units gives each one a star rating beside its CSPF, and a higher CSPF means more cooling for each kilowatt hour. Compare stars and the monthly kWh only between units with the same cooling capacity.

Which aircon is the most energy efficient?

Among units of the size your room needs, the one whose DOE label shows the higher CSPF and the lower monthly kWh. If it will run for long hours every day, Meralco points to an inverter. Size it to the room first, because a unit that is too big or too small wastes power whatever its label says.

When to call us

When the filter is clean and the unit still runs longer than it used to, book an aircon cleaning for the indoor coil and the drain, or aircon maintenance to have the outdoor coil cleaned and the gas checked as well. Tell us the unit, the town and how many hours a day it runs.

Other guides

• Aircon capacitor: what it does and the signs it has failed

  The humming outdoor unit, the fan that will not spin, and why the capacitor is tested first.

• Aircon freezing up: why ice forms and what to do

  Ice on the indoor coil or the pipes, how to thaw it safely, and the three causes behind it.

• Aircon making noise: which sounds are normal and which are not

  Clicks and water sounds that are normal, and the rattles, hisses and squeals that need a technician.

• Aircon not turning on: what to check, and the 3-minute wait after a brownout

  Remote, breaker, the compressor’s restart delay, and the flashing lamp that means a technician.

• AVR for aircon: when you need one and how to size it

  What an AVR does in a brownout, which units already protect themselves, and sizing it from the nameplate.

• Aircon watts: how many watts a 1 HP aircon uses, size by size

  Running watts and kWh per hour for each size, how to read the nameplate, and starting watts for a generator.

• Types of aircon: split type, window type, portable and centralized

  How each is installed, how noisy and costly to run it is, which rooms suit it, and what a clean has to reach.

• What is freon, and why your aircon should not need a yearly refill

  The sealed loop, why low gas means a leak, the three refrigerants in Philippine units, and the refill myth.

• Aircon HP and room size: what each size cools, 0.5 to 2.5 HP

  The square metres each size suits in a shaded room and a hot one, with the arithmetic behind 0.6 HP.

• Aircon cleaning schedule: what to clean, and how often

  The filter every two weeks, a full clean by how hard the unit works, the deeper clean, and when in the year to book it.

• Common aircon problems, symptom by symptom

  Not cold, weak air, water inside, a smell, ice, noise, tripping and blinking: what each points to and what you can check.

• Aircon lifespan: how long it lasts, and repair or replace

  How many years a unit usually gives, what shortens it, and the signs that a repair is no longer worth it.

• Inverter vs non-inverter aircon: which costs less to run

  Kilowatt hours side by side at 2, 4, 8 and 12 hours a day, and the kind of use where a non-inverter is still fine.

• What size aircon for a bedroom, living room or kitchen

  Room by room: what each kind of room adds to the size you need, worked through for a sample two-storey house.

Sources: Meralco, “Tips for the Bedroom”, “Energy-Saving Aircon Tips to Beat the Heat this Summer” and “Tips on Improving Energy-efficiency”; Department of Energy, ENERTIPS “Smart Use of Cooling Appliances” (May 2022); Hitachi Cooling and Heating Philippines, “Ways to save energy through efficient use of your AC”; LG Philippines, “How to use your Air Conditioner efficiently”; Natural Resources Canada, ENERGY STAR “Room air conditioners” (modified 19 March 2025); Republic Act No. 11285, the Energy Efficiency and Conservation Act, Section 15; Department of Energy, “List of Active Energy Labels for Air-Conditioners as of June 30, 2026”. Read 23 October 2026.