A clogged air conditioning condensate drain line can be a real hassle, especially if the line empties into a bathroom sink drain. However, cleaning out the clogged drain line isn't difficult if you know how to do it. Keep reading to learn more about condensate drain line clogs as well as how to clean them yourself.
What causes your drain line to clog?
Central air conditioning units remove a considerable amount of moisture from the interior air, especially in humid environments. Most of the time, this water is quietly drained from the system into a special pipe "tee" located underneath a bathroom sink. However, bacteria or mold growth can occur inside the wet, dark line and clog it with slime.
If you have noticed water in the evaporator overflow pan, your unit's condensate drain line is probably clogged and water is backing up as a result. You must respond quickly to prevent the water from overflowing the pan and causing damage to your home.
How can the drain line be unclogged?
The simplest way to clean the drain line is by suctioning the drain line from the sink; this will pull the slime and other materials out of the drain line in the same direction as the condensate flows. Below is a list of tools as well as a step-by-step procedure:
Tools and materials needed
1. Access the the sink drain - The condensate drain will be attached to the bathroom sink drain via a tee that is immediately above the P-trap, so you will need to disconnect the P-trap to gain access to the drain line. First, place the bucket beneath the P-trap to capture water that might spill from the trap or drain during the removal process. Next, use adjustable pliers to gently grasp the ring that fastens the trap to the vertical pipe above and turn it counterclockwise to loosen it. Once the ring has been loosened completely, pull the P-trap down and rotate it out of the way; you do not need to remove the trap completely.
2. Prepare the sink to make it airtight - In order for the vacuum to apply suction just to the incoming condensate drain line, you will need to seal any other areas where air can escape. For most sinks, there are two points where this can occur: the pop-up drain and the overflow drain. As a result, close the pop-up drain so it forms a tight seal against the sink basin, then place a small strip of duct tape over the sink's overflow drain located high on the sink rim.
3. Tape the vacuum nozzle to the sink's drain pipe - Position the nozzle of a wet/dry vacuum immediately below the sink's vertical drain line, then while holding it in place, wrap duct tape around the joint between nozzle and drain. Use three to four wraps of tape to form a secure, airtight seal between the sink and nozzle.
4. Suction the material from the condensate drain line - Once everything is sealed and attached, there should be a direct path between the wet/dry vacuum and the entrance to the condensate drain line at the evaporator unit. Turn on the vacuum and allow it to begin sucking the slime and other clog-causing material from the drain line.
Allow the cleaner to run for one or two minutes to fully suction the line, then turn it off. Unwrap the tape around the hose nozzle and sink drain, then pull away the nozzle. Replace the P-trap by aligning its top opening with the drain pipe and turn the ring to reconnect the trap to the drain pipe threads. Keep turning the ring until it is hand-tight. Finally, use adjustable pliers to turn the ring clockwise less than one-fourth of a full rotation. Do not tighten it further, or you may crack the P-trap or cause damage to the drain pipe.
If there are complications during the process, or you aren't comfortable doing this yourself, reach out to a local plumber, such as A Absolute Plumbing & Heating.