AC leaking — do this now
- Turn the system off at the thermostat to stop producing condensate.
- Soak up standing water around the unit.
- Check the drain pan under the indoor unit — is it full or cracked?
- Look at the condensate line where it exits the house — is water coming out?
- Check the ceiling below if the unit is in an attic. See ceiling water damage.
- Call an HVAC technician for the unit, and Vault at (385) 250-2825 if drywall, flooring, or insulation got wet.
Why AC units leak
Clogged condensate line
The most common cause. Algae, dust, and debris build up in the drain line until water backs up into the pan and overflows.
Cracked or rusted drain pan
Older metal pans rust through; plastic pans crack. Water leaks out slowly, often unnoticed for weeks.
Frozen evaporator coil
A dirty filter or low refrigerant lets the coil freeze. When it thaws, more water than the pan can handle.
Failed condensate pump
Basement and some attic units use a small pump to move water out. When it fails, the reservoir overflows.
High-efficiency furnaces in winter
Condensing furnaces also produce water. The same line-clog and pump-failure problems can happen in heating season.
Signs of hidden damage
- Ceiling stains below an attic unit
- Damp or musty-smelling carpet near a basement furnace closet
- Swollen baseboards or flooring next to the unit
- Musty smell when the system runs. See musty smell in your house.
Prevention
- Change filters on schedule.
- Have the condensate line flushed during annual service.
- Add a float safety switch that shuts the system off if the pan fills.
- Put a secondary pan with its own drain or float switch under attic units.
Typical Utah cost (damage only)
| Scope | Typical range |
|---|---|
| Small area around a basement unit | $600-$1,800 |
| Attic unit leak into ceiling, one room | $1,500-$4,000 |
| Long-term leak with mold | $2,500-$7,000+ |
HVAC repairs are separate. Slow leaks over weeks are usually treated as maintenance by insurers; sudden overflows may be covered.
AC leak caused damage?
Call (385) 250-2825. We’ll dry it and check for mold.
Water damage services · HVAC cleaning · Mold in attic · Hidden water damage signs
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