Your air conditioner doesn't just cool the air; it removes moisture. This water drips into a pan and flows out through a PVC pipe drain line.
Over time, algae and mold love to grow in this dark, wet pipe. Eventually, they form a clog. When the water can't drain, it backs up into your attic or closet and overflows, causing major water damage to your home.
⚠️ Do NOT Use Bleach
Bleach can damage the PVC glue and corrode older metal pans. Use plain distilled white vinegar instead. It's safe and effective.
Preventative Maintenance: The Vinegar Flush
You should do this once a year, ideally in the spring.
Step 1: Locate the Drain Line Access
Find your indoor unit (in the attic, garage, or closet). You should see a white PVC pipe coming out of it. Look for a T-shaped fitting with a removable cap on top. This is your cleanout access.
Step 2: Pour the Vinegar
Remove the cap. Pour 1 cup of distilled white vinegar slowly into the pipe. The acidity of the vinegar kills the algae and mold.
Step 3: Let it Sit
Let the vinegar sit in the pipe for about 30 minutes. This gives it time to break down the gunk.
Step 4: Flush with Water
After 30 minutes, pour a bucket of warm water down the pipe to flush everything out. Go outside to where the drain line exits (usually near the foundation) and make sure water is flowing freely.
Pipe Already Clogged?
If water is already overflowing, vinegar won't help fast enough. You need high-pressure nitrogen to clear the blockage.
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