Remove Rust From The Outdoor Condenser Unit That Is Part Of Your Home's Central Air Conditioning System

Posted on: 27 July 2016

If the outdoor condenser unit that is part of your home's central air conditioning system is often exposed to moisture and high humidity, you may have noticed that rust has formed on its exterior and interior components. If the corroded areas are not eliminated, they can become larger and damage key parts that are needed for the unit to operate properly. Learn how to remove rust spots, clean the condenser, and apply a rust inhibitor to it in order to protect the condenser unit from rusting again.

Materials Needed

  • water hose​
  • screwdriver
  • rust dissolving agent
  • sponges
  • wire brush
  • bucket of soapy water
  • rust inhibiting spray
  • drop cloth
  • rubber gloves

Remove Loose Debris From And Apply A Rust Dissolving Agent

Turn off the central air conditioning system. Go outside and spray the condenser unit's exterior to eliminate loose debris. Use a screwdriver to assist with loosening and removing hardware that is attached to the unit's cover before removing it. Spray the interior parts of the condenser with water to remove dirty residue. Wipe a sponge that has been dipped into a rust dissolving agent to treat rust spots.

Many rust dissolving products come in a gel form that will not drip while being applied. Wait a few minutes for the rust spots to begin dissolving. Afterward, move a wire brush swiftly back and forth over each spot. Apply more of the rust dissolving agent if it is needed. Rinse the treated portions of the condenser off with water when finished. 

Eliminate Stains And Apply A Rust Inhibitor

Fill a bucket with water and a small amount of detergent. Clean stained parts of the condenser unit's interior and exterior with a soapy sponge. Rinse the sponge out with water and move it over the same parts of the unit. Wait for the unit's interior and exterior to dry. Place a drop cloth on the ground, next to the condenser unit so that the rust inhibitor does not spill onto the grass or pavement.

Put on a pair of rubber gloves and apply an even coat of rust inhibiting spray to the inside of the condenser unit. Apply a coat of the spray to the condenser's cover, as well. Wait for the inhibitor to dry. Once this occurs, replace the condenser unit's cover and secure it. Turn the power to the central air conditioning system back on. Keep the condenser unit maintained by occasionally removing debris from its cover and wiping off its interior and exterior parts.

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