A central air conditioner's cooling process starts outside the home in the condensing unit. When you adjust your thermostat, an electrical signal is sent to the unit's compressor, which pumps gas refrigerant into the condensing coils. The coils change the gas into a liquid so that it can travel easily inside your home to the furnace to finish the cooling process.
Condensing coils heat up while transforming the refrigerant due to the chemistry of the phase change. The condensing unit has a blower fan pointed at the coils to keep the surface from becoming too hot. But dirt and debris on the surface of the coils can increase the temperature and make the fan less effective, which puts your system at risk of shutting down due to overheating.
You can easily clean the condensing coils on your own to prevent overheating and to improve the general efficiency of your unit. If you feel uncomfortable with any step of this process, or want to have your whole system serviced at the same time, call in a HVAC technician like one from Advanced Heating & Air Inc.
What You Need:
- Commercial coil cleaner
- Soft-bristled brush
- Hose or spray bottle filled with water
Step 1: Access the Coils
Turn off the power to your condensing units using the fuse box next to the unit. If you're unsure that the power is fully off, flip the breaker inside your home for the air conditioner. You will be using water near electronics, so you really want to make sure that power is turned off.
Look at the grate on the unit and find where the top of the grate removes. Remove the top and set it safely off to the side. Note that you might need a screwdriver to remove the grate or it can have simple levers that you push to release the lid.
Lean over the opened unit and locate the condenser coils that line one of the interior walls.
Step 2: Clean the Coils
Remove any twigs or larger debris from the coils using your hands. Don't put too much pressure on the coils as they do bend relatively easily and that can interrupt the flow of the refrigerant. Once you have the large debris removed, prepare your commercial coil cleaner according to package directions.
Spray the cleaner on the coils, trying to avoid a pool of cleaner at the bottom of the condensing unit. Allow the cleaner to soak on the coils according to package directions.
When that time has elapsed, you can use a soft-bristled brush to remove any lingering dirt. Gently clean the coils in small, circular motions.
Step 3: Rinse the Coils
You now want to rinse off any excess cleaner or remaining loose dirt, but you again want to be careful not to get moisture into the bottom of the condensing unit. If you are well-practiced with your hose and have a steady hand, point the hose at the coils from the inside of the unit and spray the coils clean with a gentle stream of water.
Nervous about using a hose? Fill a spray bottle up with water, hold the bottle close to the coils on the inside of the unit, and spray outwards until the coils are rinsed.
Reassemble your condensing unit and restore power to the unit.