Same-day AC repair
By Arman Hakobyan, lead technician1 min read
An AC removes moisture from the air and drains it through a condensate line. Water inside the house almost always means that line is clogged with algae or the drain pan is cracked or rusted. Switch the system off at the thermostat to stop the water, then have the drain cleared and the safety float switch checked.
Do this right away
- Set the thermostat to Off so the coil stops producing water.
- Put a bucket or towels under the leak and move valuables away.
- If water comes through a ceiling, check for a sagging spot; poke a small hole to drain it into a bucket rather than letting the drywall fail.
- Check the filter; a frozen coil that thaws can overflow the pan.
Why it happens
- Clogged condensate drain: algae and sludge build up over a season. The most common cause, especially with attic units.
- Cracked or rusted drain pan: common in air handlers older than 15 years.
- Failed condensate pump: in closets and basements where water must be pumped out.
- Frozen coil thawing: low airflow or low refrigerant causes ice, which melts faster than the drain can carry it.
- Missing or failed float switch: the safety switch that should shut the system off before an overflow.
How we fix it
We clear and flush the drain line, treat it to slow algae regrowth, test or add a float switch, and check the pan. Drain service starts at $189. A maintenance plan includes a drain flush every spring, which prevents most of these calls.
Questions
Is a leaking AC dangerous?
The water itself is not, but it damages drywall and insulation quickly and can lead to mold. Switch the system off until it is fixed.
Can I clear the drain line myself?
Many systems have a cleanout tee where a wet-dry vacuum can pull the clog from outside. If the water keeps coming back, the pan or float switch needs attention.
Need it fixed today?
Open Mon-Sun 7 AM-9 PM. 24/7 emergency line.
Arman leads diagnostics at Airwork. He has spent nine years on residential systems across the San Fernando Valley and the foothills, from 1950s ranch houses with attic ducts to new heat pump installs, and writes our guides from what he sees on calls.
Airwork Heating & Cooling, Burbank, CA (CSLB #1148919). Published .More guides
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