By giving your air conditioner regular attention, you can keep it both energy efficient and also improve cooling. To maximize air conditioner efficiency, consider performing these energy saving tips yearly prior to each cooling season.
A typical Heating, Ventilating, and Air-Conditioning system (HVAC) consists of either a furnace and air conditioner or a heat pump that both heats and cools. Both systems have an interior evaporator and blower unit and an exterior condenser coil and compressor unit. The following tips will improve the air conditioner efficiency of either type of HVAC system.
Safety First! We can’t stress that enough. Working around electricity and an air-conditioner’s moving parts is dangerous! Always turn off all power to the unit before you begin. On an exterior condenser/compressor, there may be an exterior shut-off box near the unit. Also turn off the power at the indoor breaker box. Once all maintenance steps are complete, turn on the power and check the unit for proper operation.
- Clean the outside unit. — Remove any debris from the exterior condenser / compressor. Use a screwdriver or wrench to remove the fan cage. Remove all of the fasteners and lift the cage or fan grill away from the top of the unit. By hand, or with a wet / dry vac, clean any leaves, twigs, dirt, or other debris from the unit’s interior and remove all outside dirt. Then, use a garden hose to carefully spray a gentle stream of water through the fins. Spray from the inside of the unit to the outside, removing all built up dirt and other debris from between the fins. Don’t use high water pressure or a pressure washer to clean the fins because the pressure might bend and damage the delicate fins. If they are especially dirty or clogged, a commercial fin cleaning spray is available at your local home improvement center or on line. To use, carefully read and follow the manufacturer’s instructions.
- Straighten the Fins — Any reduction or restriction to the air flowing through the fins will result in reduced efficiency. Carefully straighten any bent fins using a butter knife or commercially available fin straightening tool. Be careful not to damage the delicate tubing embedded within the fins.
- Clean the Area Around the Unit — Once the cleaning is complete and the fan cage replaced, rake away any leaves and debris outside and around the unit. Trim branches and vegetation back at least two feet to allow good airflow around the unit. In the winter when the condenser is not being used, cover the top of the unit with a sheet of plastic or plywood to keep falling debris out. But don’t completely cover the entire unit as moisture will build up inside and cause corrosion. Be sure to remove the top cover before operating the unit.
- Level the Unit — The pad the condenser unit sits on might shift over time. A condenser unit that is not level can result in early compressor failure. Check to see if the condenser is level and use decay resistant wooden shims for any needed correction. With a heat pump system, a slight sloping away from a home’s foundation is allowed to permit defrost to run-off during winter use.
- Clean the Evaporator Coil — On the inside unit, locate the evaporator coil cover. Remove the foil tape and screws or bolts and use a soft brush to clean the coil. Then use a no-rinse coil cleaner spray available at your local home improvement center. The spray will foam and drip into the drain pan. Rinse out the drain pan using hot soapy water and bleach. Pour about a cup of half bleach and half water down the pan drain. If the bleach solution drains out quickly, you can skip the next step. Otherwise, proceed with cleaning the drain. Then reattach the evaporator coil cover using foil tape to re-seal.
- Clean the Evaporator Drain — The pan drain usually consists of a drain tube that is routed into the home’s plumbing drain system or to the outdoors. Algae and mold will often build up and clog the drain. If the drain is not draining or if it is draining slowly, it needs to be cleaned. First, locate where the drain line exits the coil enclosure and try to follow it to the end. If the end can be located, the line can often be cleared with a wet/dry vacuum. Otherwise, compressed air can be used from the pan end of the line to clear out any clog.
- Change the Filter — The filter in your HVAC system should be replace a minimum of two times a year. Do this right before the heating season begins and again right before cooling season begins. In areas that are dustier than normal, the filter should be replaced more often as needed. Always use a new filter of the correct size that has the same airflow rating.
Air purifying or HEPA filters can dramatically reduce airflow in your system and possibly result in the freezing of the indoor coil due to the reduced airflow. The filter enclosure is located where the fresh air return duct enters the unit. A screwdriver may be needed to turn a latch to open the door to the filter enclosure. Remove the old filter and then install the new filter, making sure the flow direction arrow on the filter points in the direction of the air flow. It’s a good idea to write the date of replacement on the frame of the new filter before installing. Then close and latch the filter enclosure door.
Know When To Call the Professionals
Following these home cooling ideas each year should help to keep your HVAC system in top shape, but there will always be maintenance steps that only a trained HVAC technician should do.
A problem such as a slow refrigerant leak might eventually cause a compressor failure, but special skills and tools are required to check refrigerant levels. Keeping ducts clean to ensure a proper air flow is necessary for an energy efficient system, but most homeowners don’t have the proper equipment required.
While basic HVAC maintenance can be performed by most homeowners, periodic inspections by expert technicians are still essential to maintain and maximize long term air conditioner efficiency and help save money.