Here are some helpful tips on managing your AC energy costs:
Don’t use your AC in mild weather. Use vents or fans instead whenever possible.
Keep your house closed tight when the AC is on. If ventilation just isn’t enough to keep you comfortable, seal up the house completely and leave the AC on 24/7. It is important to restrict outside air from entering your home. You overwork your AC if it has to process hot moisture-filled air from outside.
While running your AC, keep all doors and windows closed and make sure all duct work is well insulated and sealed properly. Some ACs have an option to bring in fresh air from outside. Use this sparingly, for the same reason as above.
Reduce the areas you cool
Don’t cool unoccupied rooms. Though closing vents can help manage air flow, it is important to remember that closing too many vents will increase the system’s internal pressure and may result in damage to your AC unit or your ducts. If unoccupied areas are on a separate system, that system may not have to run or be set at the same settings as the occupied areas.
Set your thermostat high
Using fans to aid in air circulation can help reduce dependency on air conditioning equipment. If you turn on fans, especially ceiling fans, you might be able to get by with your thermostat set as high as 77 or 78. Raising your thermostat by one degree can save you as much as 5% on your energy bill.
The lower the humidity the more comfortable you will be at higher temperatures. Your AC is a dehumidifier, so don’t overwork it by introducing moisture saturated air:
- Run the exhaust fan while you shower.
- Vent your clothes dryer to the outside of your house.
- Keep plants outside in summer (when you water them, most of that water ends up in the air).
Have your AC serviced regularly
Regular maintenance is required for air conditioners and heat pumps to sustain top efficiency.
- Clean the filter on AC/Heat Pump units monthly. Dirty filters damage the unit.
- The condenser should be cleaned professionally every 2 years, or yearly in dusty conditions.
- Central AC units should be professionally tuned and inspected every 2 or 3 years. Two major items to check are:
- Refrigerant charge
- Temperature difference between intake and outflow
If either of those is bad, you'll either lose efficiency (money) or damage your unit.
Shade your AC unit
The outside part of your central AC unit should be in a cool, shaded, well-ventilated place. The best location is on the north side of the house, under trees or tall shrubs. Don’t get shrubs too close, though, or air flow will suffer and you'll lose efficiency (money).
Never put it on the roof or the east/west side of the house, unless it’s somehow completely shielded from the sun.
These guidelines may be hard to accomplish with window AC units, but it’s worth it if you can manage it.
Heat pumps are more complicated. They should be on the south side, especially in colder climates, to take advantage of the sun’s heat in winter. During summertime cooling use, you must still shade it completely with a screen or with tall plants that lose their leaves in winter.
Turn it off
Leaving your AC unit powered on all winter wastes energy and money. Switch it off completely, or turn off its circuit breaker. Restore power a day before you use it again to keep from damaging it.