Cleaning Coils in an Air Conditioner: A How To

Cleaning Coils in an Air Conditioner: A How To
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The working principle of an air conditioner is based on heat transfer from inside air to outside air. This work of exchanging heat is done with the help of air conditioner coils. Two types of coils are used in an air conditioner:

1. Condenser Coil

The condenser coils are placed in the outer part of the air conditioner. These coils are made up of aluminum and cover the air conditioner compressor. A fan is fixed inside the system, which is responsible for moving air across the condenser coils. These types of coils are affected by debris from trees, lawn mowing, and airborne d­ust.

2. Evaporator Coil

This type of coil is fixed inside the air conditioner at the main duct junction that is above the furnace. These coils are responsible for changing the state of refrigerant from liquid to gas.

The process of air conditioning is based on a state change cycle of refrigerant. The refrigerant is changed to gaseous form by evaporator coils. This gas is then passed through the compressor, which compresses the gas under high pressure. This process increases the temperature of the gas, which is then passed through the condenser coils. The work of the condenser coil is to change the hot gas back into a liquid. This liquid comes back to the evaporator coils, and the cycle repeats again and again.

Coils blocked by dirt and dibris will affect the working cycle. This results in the failure of the compressor and the air conditioner stops working properly. Cleaning the coils in your air conditioner is necessary to increase the service life of compressor and the efficiency of the air conditioner.

Here, we take a look at cleaning solutions for air conditioner coils and fins.

Steps to Clean Condenser Coils

You will need a few tools before cleaning these coils. Make sure you have a fin comb, soft brush, grass shears, carpenter’s level, pry bar and coil cleaner. These tools will make the whole process simple.

Here is the step by step process:

  • Remove grasses, weeds or trailing plants that have grown around the condenser. They restrict the air flow through the condenser coil.

  • Clean the condensor coils with a coil cleaner. Commercial coil cleaners are readily available in the market and are very effective.

  • Clean the fins with a soft brush to remove collected dirt. Remove the protective grill very carefully to reach the fins of the condenser unit. A tool called a fin comb is used to make the fins straight.

  • It is very important to make the level of condenser unit horizontal. Check the level of the concrete pad on which the condenser sits with the help of carpenter’s level. If the condenser is not horizontal then make it in level with a pry bar and shims.

  • After all the above steps, all the parts of the condenser unit that are disturbed from their places for cleaning should be placed in their particular place carefully.

Steps to Clean Evaporator Coils

Evaporator Coils

Actually, you do not need to clean these coils regularly as you do with condenser coils. These coils are not in direct contact with outside dust. It is enough to clean them once a year.

You will need different tools to clean these coils: Make sure you have a screwdriver, stiff brush, a large hand mirror and household bleach.

Steps for cleaning these coils are as follows:

  • Remove the foil-wrapped insulation that is fixed at the front of plenum. An access plate is situated using several screws behind this insulation. You will need to remove this plate with the help of the screwdriver.

  • Now, you will be able to see the dust on the evaporator coils. Clean the evaporator coils with a stiff brush. A large hand mirror will help you to see the dust.

  • There is a tray below the evaporator unit that can also be cleaned with the stiff brush.

  • If you are unable to reach every part of the coil you can pull the evaporator unit out a little. This will help you to clean properly.

  • You can put household bleach into the weep holes of the tray to prevent fungus and mold buildup.

  • The last step is to fix all the parts of the entire unit in their places. Be careful.

Disclaimer: This is a generic how-to article and should not be taken as professional advice. Please use caution and know we are not responsible for any damage you may do to yourself or your air conditioner. If you have any doubts about the process call a professional service provider.


Content from author’s own experiences.

Image Evaporator Coils-