How to Clean a Central AC

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Updated August 19, 2022

If you are new to the world of indoor cooling, you may wonder how to clean an air conditioner as part of regular maintenance. Even the best air conditioners, after all, become dirty after prolonged use. So how do you go about cleaning a central AC unit? Keep reading to find out.


  • Keeping your central ac cleaned and properly maintained is important to lengthen the overall lifespan of the outdoor unit and avoid costly repairs.
  • The cleaning process is fairly simple, requiring common household tools, in addition to a wet/dry vacuum.
  • If you lack a wet/dry vac, rent one from a local hardware store, borrow one from friends, or use a traditional vacuum.

How to Clean a Central Air Conditioning Unit

This process differs from model to model, much like when learning how to clean a portable air conditioner. Keeping your AC clean and maintained goes a long way toward minimizing damage, so you won’t have to fix a central AC not blowing cold air, among other issues. Here are the steps to cleaning a central air conditioning unit.

Insider Tip

Exercise extreme caution before cleaning the unit to be sure it is sufficiently cut off from power.

STEP 1 Shut Off Power

  1. If you are wondering “do I need a permit to replace an air conditioner,” the answer is no, however you do need to shut off the power before cleaning it.
  2. There will be an outdoor shutoff switch near the condenser unit, resembling a square box on the wall.
  3. Turn the included switch to the “OFF” position.
  4. To be extra safe, find the circuit breaker box and switch that to the “OFF” position as well.

STEP 2 Vacuum the Condenser Fins

  1. Do you see those narrow slats of metal lining the sides of the compressor? Those are the condenser fins.
  2. Run the nozzle of a wet/dry vacuum over these fins, removing debris, which allows the compressor to pull in the air without any issues.
  3. While you are at it, straighten any crooked or twisted condenser fins gently using a butter knife or kitchen utensil.
  4. Rent a wet/dry vac or borrow one from friends if you lack this tool.

STEP 3 Unscrew and Remove the Fan

  1. The fan is located on top of the compressor, covered by a metal grate.
  2. Use a screwdriver to remove the wiring on top of the fan, unscrew all relevant areas, and remove the fan.
  3. If removal isn’t possible, just lift it as far as you can from the housing for cleaning.

STEP 4 Wash the Fan and Reassemble

  1. Use a garden hose to rinse debris and dust from the fan blades.
  2. Follow this with a clean cloth or rag, wiping down the fan as needed.
  3. Use the hose again to spray water through the compressor fins to the interior of the unit.
  4. Put everything back together, working in reverse from the disassembly procedure.


Should you clean AC coils?

Cleaning evaporator coils is a crucial part of the process for some AC units, but for others, you should wait for a professional before tackling those evaporator coils. Discuss the specifics of your air conditioner unit with a pro.

How do you clean the outside AC unit?

Use a garden hose or a pressure washer on low power, taking care to follow the above steps.

Does spraying water on my air conditioner help it run more efficiently?

Yes, spraying the condenser fins can help with the efficiency of your outdoor unit, but it really depends on the make and model and the specifics of regular cleaning methods.

STAT: Air conditioner units consist of a condenser (which itself contains the compressor, cooling tubes, and a fan), an evaporator (the large internal unit which cools the air), tubes to drain moisture from the dehumidified air, and a fan to blow the cool air out into the house or apartment. (source)

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