AC Leaking Water in Los Altos Hills, CA

AC Leaking Water in Los Altos Hills

An AC pulls moisture out of your air and drains it away as condensate. When water turns up near the indoor unit, that drainage has failed. Maybe the line is clogged. Maybe the pan cracked, or is simply overflowing. Maybe the pump quit, or the float switch that should have caught it stuck. In nearly every case it is one part, and the system itself is fine.

The foothill climate matters here. Los Altos Hills sits above the South Bay, warmer and drier than the bayside towns, and the cooling side genuinely earns its keep through summer. That means these systems run long and hard and push real volumes of condensate through their drains. A line that was marginal all along clogs when it finally has to move that much water.

These are large estates with spread-out floor plans, usually more than one air handler, and long line sets running across steep lots. Condensate routing here is rarely short or simple, and the air handlers often sit in attics over finished space. We find which unit is leaking, trace the drainage, and put the repair on a written estimate first.

Common causes

Clogged condensate drain line. The most common leak we find. Hard summer runtime moves a lot of water, and any algae or debris in the line eventually backs it up into the pan. We clear the line with a wet vac and flush it, confirm free drainage, and add a treatment tab at the cleanout when there is one.

Cracked or overflowing drain pan. When the line plugs or the pan cracks, water spills from the air handler. On attic units over finished rooms that means a ceiling stain below. We inspect the primary and secondary pans, clear the secondary drain, and replace a cracked or corroded pan.

Failed condensate pump. The spread-out plans and steep grade here often mean an air handler can't drain by gravity and depends on a condensate pump. A dead motor or stuck float floods the unit. We test the pump with its reservoir filled and replace it when it won't kick on.

Frozen evaporator coil melting off. With AC running hard in this heat, a low refrigerant charge or a clogged filter freezes the coil, and the ice sheds far more water than the pan holds when it thaws. We read refrigerant pressures and coil temperature to find the real cause rather than just clearing the water.

Stuck float safety switch. The float switch should shut the AC down when the pan fills. Stuck open, the system keeps running and overflows. We test it and replace it if it isn't interrupting the circuit, then confirm it actually stops the unit.

Long line-set or zoning airflow problems. On these large multi-zone systems, a stuck zone damper or a restricted long line set can starve one coil of airflow and freeze it. We check damper operation and airflow as part of the diagnosis so the coil doesn't just freeze again after the repair.

How we diagnose it

Identify which system on the estate is leaking and locate its air handler.
Clear and flush the condensate line and confirm it drains, checking the full run on these long routes.
Inspect and clear primary and secondary pans and drains for cracks and overflow.
Read refrigerant pressures and coil temperature to rule out a frozen coil in the summer heat.
Test the condensate pump, float switch, and zone damper operation to pin the failed component.

$75 diagnostic, credited toward any repair over $200. You get a written quote before any work begins.

AC Leaking Water in Los Altos Hills: common questions

Will you drive out to Los Altos Hills for this?

Yes. Los Altos Hills is one of the 39 Bay Area cities we serve from our San Ramon base. A leaking unit is a same-day priority when we have the slot, because standing water reaches the blower motor and control board quickly. We'll give you a straight answer on timing when you call.

It gets hot here. Could the heat itself be causing the leak?

Indirectly, yes. The real cooling load in these foothills means the system runs long and hard, which both moves more condensate through the drain and makes a low refrigerant charge or dirty filter freeze the coil. A frozen coil melting off looks just like a drain leak. We read pressures and coil temperature to tell the two apart before quoting anything.

Is a leaking AC an emergency?

It's urgent, not catastrophic. Turn the system off so water stops reaching the blower, the board, and the ceiling below. The underlying fix is usually a small drain or pump repair, often $150 to $450, but the water damage it causes if left running is the expensive part. Shut it down and call.

Nearby and related

AC Leaking Water near Los Altos Hills: Los Altos · Palo Alto · Mountain View · Cupertino .

This is usually a ac repair in Los Altos Hills job. See our ac repair overview or the Los Altos Hills service area.