What To Do When Your A/C Drain Line Is Clogged

It’s a beautiful warm day in sunny Tampa, and you go to turn on your AC only to be met with…nothing. While there are many reasons why cool air isn’t coming from your air registers, a clogged drain line is often the culprit!

Our team at Super Heat & Air discusses why this happens and some easy ways to fix a clogged drain line. Let’s go!

Signs of a Clogged Drain Line

Two common signs of a clogged drain line are:

A leaking drain pan
Your AC won’t start

The drain line and pan are at the bottom of your HVAC unit’s air handler. As the system runs, moisture from the air condensates on the indoor coil, and runs off into the pan and then down the drain.

Sludge can build up over time in the drain line and is usually composed of dust, dirt, mold, and algae. Drain line clogs are especially common in areas of high humidity.

If your AC won’t start, the drain pan might be full due to a clog in the drain line. If the condensate cannot drain, the drain pan will fill up, and the float switch will shut down the AC to prevent damage.

If you find puddles or the area around your air conditioner is wet, shut the system down immediately. The float switch might have failed, and your drain pan is overflowing.

How to Unclog a Drain Line

While inconvenient, unclogging the drain line is simple. There are two approaches that you can take:

Clearing the drain line by hand
Using a vacuum

Super Heat & Air tip: We recommend using both methods to ensure that the pan is empty and that the drain line is clear.

Clearing a Clogged Drain Pan by Hand

The first step is to find the drain pan. It can be found beneath the indoor coil in the air handler. Next, you’ll clean the drain line and the pan.

Clean out the pan: If the pan is full of water, use a wet vac or towel to remove the water. Scrape out any debris or sludge that you find there.

Locate the drain line: When you find the hole that leads to the drain line, use a thin stiff wire brush to clean the hole as far as you can reach. Then, check the line that leads outside your home, if it is dripping, this means that you have cleared the clog. If not, there might still be a clog in the drain line.

Sanitize: Mix 1 cup of bleach with half a cup of water. Pour the mixture into the pan to sanitize the pan and drain line and help prevent future clogs. Or for an eco-friendly option, use 2 cups of undiluted white vinegar instead of the bleach mixture.

Unclog the AC Drain Line with a Vacuum

This approach cleans the drain line from the drain outside your home up to the drain pan.

A shop vac might be enough to clear the clog without needing to go into the attic where your air handler is.

Located the condensate drain outside your house.
Fit the end of the vacuum over the condensate line and secure it with duct tape.
Turn the vacuum on for a few minutes.
Your drain line should be clear!

Related Reading> What to Do if Your AC Drip Pan is Full of Rust

Clear a Clog Fast!

If these DIY steps don’t help when your AC drain line is clogged, or your HVAC system is still not working even when the drain line is cleared, it’s time to bring in the pros!

Our technicians at Super Heat & Air can clear your clogged drain line and troubleshoot your entire system. And don’t forget about our Super Fast Guarantee!

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