Talking About Air Conditioners

2 Common AC Condensate Drain Problems

Condensation is a natural byproduct of any AC or refrigeration system. Central air conditioners handle excess condensation by removing it from your home through the condensate drain. Unfortunately, issues can sometimes arise with the condensate drain that prevent your air conditioner from operating correctly. Here's what you should know about two common AC condensate drain problems.

1. Clogs and Overflows

The condensate drain and drain pan are located in a dark area under your evaporator coils in the furnace assembly. When you consider that the drain is constantly exposed to moisture, it's easy to see why algae growth can become a problem.

Algae in the condensate drain can become compacted inside the drain line and create a clog. A clogged drain can cause water to back up in the drain pan until it overflows, which can lead to significant water damage in your home. In other cases, a float switch in the drain pan may prevent your AC from running until the pan is emptied.

Adding algae tablets or strips to the condensate drain pan can do wonders to discourage algae growth. If a clog has already formed, you may be able to remove it by shutting off your AC and pouring diluted bleach or vinegar into the drain. When professional repairs are needed for a clogged condensate drain, your technician will typically remove the clog with a wet/dry vac or another specialized tool.

2. Unpleasant Odors

In most homes, the central AC condensate drain is connected to the main sewer line. A P-trap integrated into the drain line holds water to prevent the HVAC system from pulling noxious sewer gases into the home.

If the P-trap dries up, you may notice a persistent foul odor in the area around your furnace housing. The trap can dry up due to extreme cold weather or prolonged disuse of your HVAC system. Professional repairs are always the best solution for this problem.

Your HVAC technician may install a fluidic control device to manage air pressure inside the P-trap and prevent the water inside from evaporating. In some cases, redesigning the condensate drain system may be necessary to avoid future odor issues. This may include adjusting the slope of the drain line or installing a new vent pipe to blow the trap.

Condensate drain problems are rare and typically simple to solve, but they can have a big impact on the function of your central air conditioner. If you suspect that your AC condensate drain isn't working correctly, consider scheduling a professional HVAC inspection and repair.