AC Leaking Water? Check the Drain Line, Flush $75 to $250

Prices are national ranges from the publisher named. Add a $75 to $200 service call (HomeGuide, HomeAdvisor).

Do this now: AC leaking water inside

1. Turn the AC off at the thermostat. Bryant says to switch it off at the thermostat and, when appropriate, at the breaker or outdoor disconnect, which stops more condensate from forming. Carrier says running a leaking unit can make the damage worse.
2. Shut the breaker only from a dry spot. The Red Cross says not to touch electrical equipment that is wet or while you are standing in water. If the panel is in a wet area, leave it and call.
3. Catch and soak up the water. Towels and a bucket under the indoor unit. Keep cords and electronics out of the water, without touching anything that is already wet.
4. Look for ice. Ice on the copper lines means a frozen coil. Leave the system off until it melts, which Bryant says can take several hours, and do not chip at it. See why an AC keeps freezing.
5. Check the filter. Bryant lists a dirty filter as a leak cause because it can freeze the coil. Replace it if it is gray and clogged.
6. Leave the unit's panels closed. Carrier warns that AC capacitors store high-voltage electricity that can cause serious injury or death even when the power is disconnected.
7. Photograph wet ceilings, walls and floors before you clean up, and call your insurer if anything is damaged.

Why is my AC leaking water? The usual causes

A clogged condensate drain line is the most common reason an AC leaks water inside, Carrier says. The indoor coil pulls moisture out of the air as it cools, and that water runs into a pan and out a drain line. HomeGuide says a clogged line can make the pan overflow and leak. Bryant adds that an AC that leaks while it still cools most likely has a clogged drain line or a cracked pan. Other causes on Bryant's and Carrier's lists:

• A frozen evaporator coil. A dirty filter or low refrigerant lets ice build on the coil; when it melts, the water can overwhelm the drain. Carrier says this is why some ACs leak after they shut off.
• A damaged or rusted drain pan, more common on older units (Bryant).
• A condensate pump that has failed, clogged or lost power (Bryant).
• A disconnected or damaged drain line, or a unit that is not level (Bryant).
• High humidity or a system that is the wrong size, which Bryant says can increase condensate.

How to unclog an AC drain line

A wet/dry vacuum can clear a minor clog from an AC drain line, Bryant and Carrier say, but Bryant adds the caveat that you should only try it if you can safely identify the drain and how it connects. With the system off:

1. Find where the drain line leaves the unit and check that end for a visible clog (Bryant).
2. Hold a wet/dry vacuum hose over the end of the line and pull the clog out (Carrier).
3. Check that the line slopes so water flows freely (Carrier). The DOE also suggests passing a stiff wire through the unit's drain channels from time to time.
4. Look at the pan. If it still holds water, or you cannot tell which pipe is the drain, stop and call.

A dealer quoted by Bryant advises leaving drain maintenance and treatments to a licensed dealer because doing it incorrectly can damage the equipment. A professional flush runs $75 to $250 in HomeGuide's guide, and Bryant says clearing a clogged line is often under $150.

How to clean an AC drain line so it stays clear

ENERGY STAR puts checking the condensate drain on its yearly maintenance checklist, and Bryant recommends professional AC maintenance at least once a year, ideally in spring. Between visits:

• Replace the filter every 1 to 3 months, as Bryant and Carrier suggest. The DOE says a clean filter can also cut AC energy use 5% to 15%.
• Ask the technician at the spring visit to clear the drain line and check the pan. Bryant mentions drain tablets or pads as one preventive treatment.
• Book a yearly AC tune-up before the hot months.

Is water dripping from an AC dangerous? When it is an emergency

Water dripping from an AC is an emergency when it is damaging a ceiling, floor or drywall, or when a refrigerant leak is involved, Carrier says. The clock matters: the EPA says wet materials dried within 24 to 48 hours usually will not grow mold. Treat it as urgent when:

• Water is coming through a ceiling below an attic air handler. The Red Cross warns that a sagging ceiling is likely waterlogged and dangerous, so keep people out from under it. See ceiling water damage repair.
• Water is near outlets, cords or the electrical panel. Do not touch anything electrical while you are standing in water (Red Cross).
• You hear hissing or bubbling, which HomeGuide lists as a sign of low refrigerant. Bryant says refrigerant leaks should be addressed right away, by an EPA Section 608 certified technician.
• The house is getting hot with the AC off. Hot house, someone at risk? The CDC says a fan can raise body temperature once indoor air is above 90 F; move people 65 and older, infants and anyone with heart disease or asthma somewhere cool (dial 2-1-1 to find one). Heat stroke signs such as a body temperature above 103 F or confusion mean call 911 (Ready.gov).

How much does it cost to fix an AC leaking water

Most AC water leaks cost $75 to $250 to fix when the cause is the drain line, HomeGuide says; a cracked pan, a pump or a refrigerant leak costs more. Carrier puts fixing an AC leak at $200 to $1,500 overall, depending on how bad it is and where.

National figures. HomeGuide's text and table differ on drain pans; the table figure is shown.

If the leak traces back to a frozen coil from a refrigerant leak on an older system, price a replacement too: HomeAdvisor and HomeGuide both suggest replacing an AC that is over 10 years old or uses R-22. Prices are on AC replacement cost.

Does homeowners insurance cover an AC water leak?

Homeowners insurance may cover water damage the leak caused, but usually not the repair of the AC itself, Bryant says. The Texas Department of Insurance says most policies cover sudden and accidental water damage but not gradual leaks, so a drip that went on for weeks may be excluded.

• Photograph the damage before you clean up, and keep the repair invoice that names the cause.
• Call your insurer before you hire anyone for drywall or ceiling work.
• Never sign an assignment of benefits or any contract that hands your claim to a contractor. Florida bans assignments of post-loss benefits on policies issued on or after January 1, 2023.

For drying and rebuilding, see water damage restoration; if growth has started, mold remediation.

Who fixes an AC leaking water

An HVAC technician fixes the cause: the drain line, pan, pump or a frozen coil. HomeGuide and HomeAdvisor both put the service call at $75 to $200 and say most companies apply it to the repair. Before you book, ask:

• What is the service call fee, and does it go toward the repair?
• Will you clear the drain and check the pan, the pump and the coil for ice?
• If it is a refrigerant leak, is the technician EPA Section 608 certified? It is required for refrigerant work.
• What is your license number, and can I see proof of insurance? Check the license with your state board.

If the AC also stopped cooling, start with AC not cooling; if it will not start at all, see AC not turning on. Every common fix is priced on AC repair, and the HVAC repair hub covers heating too. Compare other jobs on home repair costs.

Calls go to an independent company that serves your area and takes this kind of job. Ask for its license number and proof of insurance yourself. Some companies take emergency calls; hours vary. How calls work.