How to Troubleshoot a Central Air Condenser That Won't Drain?

Your HVAC condenser will need cleaning out every spring, or it may clog.

Your central air conditioning condenser produces a small amount of water during the cooling exchange from the house. A drain line carries this condensation away from the condenser. This drain line should be cleaned every year. Water stuck in the drain line over winter will make the right conditions for the growth of algae in the pipes. If the algae becomes too thick, the condenser line won't drain, causing your condenser to leak. Cleaning the condenser line in the spring will prevent this from happening.

Things You'll Need

• Wrench
• Bleach
• Funnel
• Shop vacuum

Instructions

1. Unplug your condenser from its outlet to turn it off.

2. Remove the cover for the drain line access hole and pour a cup of bleach into it using a funnel. Let the bleach sit for an hour to kill any mold, mildew, and algae.

3. Unscrew the drain line from the unit with a wrench to disconnect it. Let the bleach run out.

4. Remove the paper filter from the shop vacuum. Attach the end of the vacuum hose to the end of the drain pipe and wrap a rag around the two. Turn on the vacuum for a few seconds to suck out the debris.

References

• The Family Handyman; Cleaning Air Conditioners in the Spring
• Danny Lipford; AC Drain Clean Out; Joe Truini