How to Fix a Clogged Central Air Conditioning Drain
Many modern homes are outfitted with central air-conditioning systems. Maintenance on these systems is critical, especially if you are trying to sell your home. One potential issue that can occur is a clogged drain. The indoor system portion generates condensate, or water residue, that must be drained to the outside. A pipe extending from the home’s exterior wall usually allows this condensate to leave the interior, but it can become clogged with algae or other buildup. A simple clog removal process will allow you to have a properly functioning system for home inspection and a possible sale.
- Locate the drain line on the exterior of the home. This line is normally placed near or behind the outside air-conditioning unit; it is typically a black or white PVC (polyvinyl chloride) pipe extending from the wall.
- Remove the cover from the access hole on the drain line with a wrench. Each pipe might have a different cover type depending on the original installation. Consult your system’s manual for specific cover removal directions.
- Place a wet/dry vacuum near the access hole. Confirm that the vacuum is set for a wet suction process by removing any paper filters from its interior. Each vacuum manufacturer has a different setup process for wet suction procedures. Consult the vacuum’s manual for specific instructions.
- Hold the hose tightly against the access hole. Turn the vacuum on. Allow the vacuum to suck the clog out of the drain pipe.
- Turn the vacuum off. Look inside the vacuum’s storage tank by hand-releasing the cover. Visually verify that the clog entered the vacuum. There should be a visible amount of algae or other residue inside. Reattach the tank’s cover.
- Remove the vacuum from the access hole. Reattach the access hole’s cover with a wrench. Turn on the air-conditioner system and allow it to run through its processes. Water should slowly drip from the drain pipe indicating the clog has been removed.
Source: https://homeguides.sfgate.com/fix-clogged-central-air-conditioning-drain-24929.html