An air conditioner works most efficiently when the evaporator and condenser coils are clean and the cooling fins are straight. If you've never cleaned your unit, layers of dust and dirt on the coils impede heat transfer - meaning the system works harder, uses more energy, and ultimately costs you more to run. Regular cleaning is one of the simplest and most cost-effective things you can do to extend the life of your unit.
For more on keeping your system running efficiently, see our complete guide to reducing air conditioning running costs.
What You'll Need
- Screwdriver (4-in-1)
- Fin comb
- Leather or work gloves
- Rags
- Shop vacuum
- Air conditioner coil cleaner
- Electric motor oil
- Household cleaner or bleach
Step 1: Remove the Unit and Access the Coils
Before you start: turn off and unplug the air conditioner. Never work on a live unit.
Remove the plastic filter holder and trim panel - it usually snaps off. Slide the unit out of the wall or window. These units are heavy, so get an extra pair of hands if needed. If it's a window unit, remove the mounting frame and then the outer case - screws are usually along the bottom edge. Note where each screw came from before you remove them.
Step 2: Straighten the Cooling Fins
Bent fins restrict airflow and reduce efficiency. Use a fin comb to straighten them - match the correct end of the comb to the fin spacing on your coils, insert it, and pull upward. Wear gloves for this step as the fins are sharp and can cut easily.
Step 3: Vacuum and Clean the Coils
Before applying any cleaner, use a shop vacuum to remove visible dust and debris from both the evaporator and condenser coils. Then apply a foam coil cleaner over the entire surface of both coils and allow it to dwell and do its work. If there is heavy soiling, gently brush in the direction of the fins using a soft nylon-bristle brush - never brush across the fins. For evaporator coils, Coil Care Antimicrobial Evaporator Cleaner is a good option that also tackles bacteria and odour-causing build-up.
Step 4: Clean the Drain Pan
Clean the drain pan with hot soapy water and a 50/50 bleach and water solution. Pour the solution down the drain to clear any algae or debris. For ongoing prevention, drain pan treatment tablets or a regular dose of drain treatment will stop algae from re-establishing between cleans.
Step 5: Clean the Fan Blades and Top Up Motor Oil
While the coil cleaner is dwelling, wipe down the fan blades with a household cleaner and a rag. Add a few drops of electric motor oil to the fan motor oil ports if accessible - this keeps the motor running quietly and extends its service life.
Step 6: Clean or Replace the Filter and Reassemble
Wash the air filter with warm soapy water, allow it to dry fully, and reinstall. If the filter is damaged or heavily soiled beyond cleaning, replace it. Reassemble the unit in reverse order, making sure all screws are returned to their correct positions, and reinstall in the window or wall.
Switch the unit back on - it should now be blowing noticeably cooler air with improved airflow.
How Often Should You Clean Your Air Conditioner?
Clean the filter monthly during periods of heavy use. A full coil clean once or twice a year - ideally before summer - is sufficient for most domestic units. Air conditioners that are regularly maintained last approximately 40% longer than those that aren't. For more on common faults that develop in neglected units, see our guide to diagnosing and fixing common air conditioning problems.
0 comments