Residential Plumbing & HVAC Experts
Signs of a Clogged A/C Drain Pipe

Identifying a Clogged A/C Drain Line

Will a clogged A/C drain pipe cause severe water damage before you’re even aware of it? Consider this fact: on a hot summer’s day, your central air conditioner condenses gallons of water out of indoor air. Because dryer air cools more efficiently than humid air, it’s a critical part of the cooling process. Condensate drips down from the A/C evaporator coil in the indoor air handler into the condensate drip pan, then flows out through a drain pipe connected to the household sewer. As long as nothing goes wrong, you’re not even aware of this continuous cycle of water flowing from the air down the drain.

If a clogged A/C drain pipe occurs, however, the signs of the problem become hard to miss.

Signs of a Clogged A/C Drain Pipe

  • As the air conditioner keeps cycling on and extracting water from the air, the drip pan continuously overflows due to the clogged drain line. Pools of water spread out around the air handler, causing water damage to floors and walls. Because the air handler is usually located inside a dedicated closet or other enclosed zone, occupants may not immediately notice the problem. This means the severity of water damage may be compounded.
  • If the condensate drain pipe is only partially clogged and flow is sluggish, drip pan overflows may be intermittent and less conspicuous. However, this ongoing source of unseen spillage beneath the air handler will trigger toxic mold growth as well as rot the floor under the unit.

Resolving Drain Pipe Issues

If you notice unexplained water pooling in the area around the HVAC indoor air handler—or frequently smell the musty odor of mold growth in that area—shut off the A/C and call professional HVAC service. A qualified service technician can blow out the clog in the drain line and remove any debris or algae growth. In addition, he can install time-release biocide tablets in the pan to inhibit drain-clogging algae for the entire cooling season.

If you suspect a clogged A/C drain pipe, prevent further water damage by contacting the service pros at Sherlock Plumbing, Heating & Air now.