How to Clean a Room Air Conditioner

A simple cleaning is all it takes to keep your room air conditioner humming.

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Introduction

Air conditioners work more efficiently when the evaporator and condenser coils or cooling fins are clean and the fins are straight. Save money and keep your house cooler by cleaning a room air conditioner yourself.

Tools Required

  1. 4-in-1 screwdriver
  2. Fin comb
  3. Leather gloves
  4. Rags
  5. Shop vacuum

Materials Required

  1. A/C coil cleaner
  2. Electric motor oil
  3. Household cleaner

How to Clean Your A/C Unit

Most people assume warm air from their air conditioning unit means it’s low on refrigerant. That’s not always the cause. Many times, window and through-the-wall A/C units can’t blow cold air because the evaporator and condenser coils or cooling fins are clogged. Here are some air conditioning mistakes you can avoid.

Professional cleaning costs more than $100. But you can do the entire job yourself in about an hour with a few dollars in supplies. If cleaning doesn’t do the trick, you can always call in a pro (or buy a newer, more efficient unit). But before you do that, check out our step-by-step air conditioner cleaning instructions below.

Plus, here’s where you shouldn’t install your A/C.

Project step-by-step (6)

Step 1

The Cleaning Procedure:

First, remove the plastic filter holder/trim panel. It usually snaps off. Then remove the unit from the window or slide it out of the wall. (Get help. It’s heavy.)

If you’re working on a window A/C unit, remove the mounting frame and the case. The case screws are usually located along the bottom edge. Note the location of any odd-length screws since they have to go back in the same spots upon reassembly. Plus, your air conditioner won’t work fully if you don’t do this.

Step 2

Comb Out the Mats

  • Straighten the bent cooling fins with a fin comb.
  • Match the correct end of the air conditioner fin comb to the fin spacing on your coils.
  • Then insert the air conditioner fin comb and pull up to straighten the fins.
  • Wear leather gloves to prevent nasty cuts.

comb out air conditioner matsFamily Handyman

Step 3

Air Conditioner Fin Comb Details

air conditioner fin combFamily Handyman

Step 4

Clean Out the Crud

  • Buy two cans of A/C unit coil cleaner (we used AC-Safe No. AC-920 from The Home Depot.).
  • Before applying the cleaner, vacuum all visible buildup from both coils.

clean out air conditioner crud Family Handyman

Step 5

Apply Foam Cleaner

  • Shoot the spray over the entire surface of both coils and let the foam do the work for you.
  • If the buildup is heavy, brush in the direction of the fins with a nylon-bristle brush.

AC Unit Coil CleanerFamily Handyman

Step 6

Service the Fan Motor

  • While the foam works, clean the fan blades with a household cleaner and a rag.
  • If the fan motor has plastic- or rubber-capped oiling ports, pop them and squeeze in a few drops of electric motor oil (pros use the Zoomspout oiler) and recap.
  • Finally, wash (or replace) the air filter and reinstall the unit.
  • It just might blow a lot cooler. If not, you have other problems!

And if you don’t have an air conditioner, check out these creative ways to stay cool all summer long.

service air conditioner fanFamily Handyman