picture of Condensate Drain

How to Clean Your Air Conditioner’s Condensate Drain Line

Taking the time to clean your air conditioner’s drain line (or the condensate drain) can have a tremendously positive effect on how efficiently your system runs. Here’s how to quickly and safely prevent problems with your unit.

If you’ve ever taken a good look at your air conditioning unit, you may have noticed a small dripping line on the outside. The condensate drain, which plays a vital role in removing condensation produced by your air conditioner’s evaporator coil. Cleaned the condensate drain line of algae and mold which can grow inside and clog the drain, causing elevated humidity, musty odors and water damage inside your home.

Unfortunately, this part of the system is often overlooked during regular A/C maintenance. Even HVAC technicians may forget to clean the drain during a regular service call, which means that it’s up to you to check and clean the condensate pan and drain line before a problem develops. Cleaning the line will remove clogs and blockages and prevent algae and mold from growing.

You will need these items to clean your A/C condensate drain:

  • Rags/Towels
  • A wet/dry vacuum
  • Bleach and Liquid Plumber
  • A funnel

Instructions on - How to Clean Your Air Conditioner Condensate Drain

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1. Turn off the power to your HVAC system at the thermostat and at the breaker.
2. If you have an indoor air handler in your attic or utility closet, you’ll need to find the condensate pan. Sometimes it will be covered by a removable access panel.
3. If you see standing water in the drain pan, your drain line is probably clogged. Use a handheld or shop vacuum to remove the moisture. You can also use rags to soak up the water. At this point, you can clean the drain pan with soap.
4. If you have a shop vacuum, use it to pull the clog through the drain opening, located outside your house near the foundation. Place your hand on the pipe to improve suction and allow the vacuum to run for a minute. Then, check the vacuum canister to see if the clog is gone.
5. Next, you’ll need to identify the access point on the drain line. Usually, the drain will have a T-shaped vent with a PVC cover. Remove the cover (lid) and inspect the drain line. Use this port to flush the drain line with 1 cup of bleach every time you change your AC filter and pour Liquid Plumber down the drain every three months but do not flush with water. It works better if it sits in the P-Trap. Alternately, you can use hot water and a drop of dish liquid.
6. Allow the solution to sit for 30 minutes. Complete the cleaning by flushing the pipe with water. Have a helper watch the pipe outside and tell you if the water is running freely.

Other Notes:

If you don’t have a shop vacuum, you can use a piece of surgical tubing to free the blockage. Know that this method doesn’t work well if your drain line has sharp turns that are prone to clogs. If your system doesn’t have an access vent, use the opening on the edge of the drain pan. This fitting can be removed to improve access.

Underlying problems with the system can also be responsible for compromised water flow. If the pan and drain line isn’t slightly tilted, water can build up in the back of the pan and will eventually overflow. Many newer systems come equipped with overflow sensors installed within the pipe.

If you’re unable to clean your air conditioner’s drain line, call a local professional HVAC Technicians to do the job. Professionals can clean the drain line and install an access vent, if necessary. Check the drain line periodically throughout the cooling season.

Routine maintenance steps like checking your drain line can help keep your air conditioner running more efficiently.

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