How to Maintain an Air Conditioner

Steps:

1. If your air conditioner never shuts off, it may not be running as efficiently as it can be.
2. Ensure the outside condenser is debris free. Use a vacuum cleaner with a brush attachment to keep the fins clear of mold, dust, pollen, pet hair, or other contaminants.

   Condenser Care: Before the cooling season begins, pop open the condenser unit’s side covers and gently brush dirt off the cooling fins with a soft-bristled paintbrush or spray it off with a hose—never use a pressure washer, which can bend the fins. Realign any crushed or bent fins with a fin comb, available from AC dealers and supply houses, and rake up loose leaves or debris around the unit.

   
   

   Pro Tip: Richard Trethewey, This Old House plumbing and heating expert, advises: “Install condensers or window units on the north or east side of your house, or build a screen to shield them from the sun. Putting them in direct sunlight reduces their efficiency by as much as 10 percent.”

3. Periodically change the filter on the indoor air conditioning system. Use the existing one as a guide to purchase the correct size and follow the “flow” arrow when reinstalling.

Pro Tip: When it comes to filters, more efficient isn’t always better. According to This Old House Magazine, inefficient filters won’t catch much, but too high an efficiency rating can choke airflow and strain the blower. If you upgrade your filter, make sure the new one is compatible with your system. Standard 1-inch pleated filters should be replaced every month during the cooling season for optimal performance.

Pro Tip: A blocked return air filter can cause the evaporator coil to freeze, cutting your cooling power significantly. According to This Old House experts, something as simple as a dirty filter or obstructed outdoor unit can be the culprit. If changing the filter and clearing the outdoor unit doesn’t solve the problem, a lack of refrigerant from a small leak may be to blame—and that’s a job for a professional.

Resources:
The shop vacuum, brush accessory and HVAC air filter shown can be found at the local home center.

Follow these air conditioning tips to keep your home cool during the spring and summer.

If you think your system has shut down from ice build up, follow these steps to repair a frozen air conditioner.

Learn More: How to Diagnose and Repair a Humid Air Conditioner