Clean leaves and other debris from the top of the central air conditioner or heat pump.
Remove garden tools and other items from around the central air conditioner condenser unit so the air flow is not restricted.
Question: I want my old air conditioner to run as efficiently as possible. Other than a professional service call, what can I do to tune it up myself?
Answer: With temperatures rising and summer on the way, it is wise to make sure your existing central air conditioner is running as efficiently as possible.
Professional servicing once or twice a year is highly recommended for maximum cooling efficiency and as a way to extend the life of your unit, but there are some things you can do yourself to keep your central air conditioner running as efficiently as possible.
Air conditioners operate by maintaining a delicate balance of air flow rates over indoor and outdoor coils containing a refrigerant chemical. Inside the coils, the refrigerant changes back and forth between liquid and gas states, and in the process chills the air in your home while expelling hot air to the outdoors.
An important part of the process is the release of heat that occurs in the outdoor coils, which are aided by a layer of thin metal foils and a large blower fan. Sadly, the outdoor unit of a typical AC system is the part that most of us ignore because it’s out of sight and out of mind. A little routine care and maintenance will help improve its efficiency.
Whenever you do yard chores, make sure weeds and shrubs have not grown too close to the outdoor unit as they can impede airflow. Also, don’t rest rakes or other items against the cabinet.
Over time, debris can build up inside the outdoor unit, and a basic cleaning job is certainly a do-it-yourself option. Switch off the circuit breaker to the unit and remove the outdoor cabinet. Clean out any debris that has accumulated inside it, which may block the coils or impede the operation of the fan. If fins have been bent over in spots, try to straighten them out so more air gets through to the coil.
Be sure to save all the screws holding the cabinet sections together and make sure they are tight when you reinstall them. Loose spots create leaks that will draw air through the gaps instead of through the coils as designed. Between clean-ups, periodically check the tightness of the screws to ensure the integrity of the cabinet.
It’s also important to ensure proper airflow through the indoor coils. With the circuit breaker still switched off, remove the side cover on the indoor unit to expose the evaporator coils and the blower.
Indoor coils get damp when you run the AC, and they can accumulate quite a bit of dirt over time, which blocks air flow and decreases efficiency. Wipe the coils and then use the brush attachment on your vacuum cleaner to clean them and the blower as well as possible.
The final do-it-yourself step is the most obvious: Replace the blower filter regularly—every three months at a minimum. A clogged filter increases air flow resistance, which also reduces efficiency.
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