Why is water dripping out of my indoor unit instead of going down the drain?

Almost always a blocked drain line or a failed pump. The indoor coil pulls moisture out of the air every time the system cools, and that water has to leave by gravity through PVC or by a small pump. When slime, dust, or a sagging line blocks the path, the drain pan fills and spills over the edge. Shut the system off at the thermostat and call before the water finds drywall.

How much does it cost to unclog an AC condensate drain line?

A straightforward clear-and-flush visit sits at the low end of the $150 to $1,500 repair range used across standard Puget Sound markets, with affluent and luxury markets running $175 to $1,800 and $200 to $2,000. You get a price before any work starts. If the line has to be re-piped or a pump replaced, the number moves up within that range.

How long does a condensate pump last?

Most residential condensate pumps run five to ten years. They are small, inexpensive, mechanical, and they live in a wet environment, so they are a wear item rather than a lifetime component. A pump that hums without moving water, cycles constantly, or trips the safety switch is usually at the end of its life rather than repairable.

Can I pour bleach down my condensate drain line?

We do not recommend it. Bleach degrades some drain pan materials and metal components in the air handler cabinet. A cup of distilled white vinegar poured into the access tee once or twice during cooling season is the safer home maintenance step, along with keeping the air filter clean so less dust reaches the coil.

Does a clogged drain line mean my whole AC needs replacing?

No. A clog is a maintenance failure, not an equipment failure, and the fix is usually inexpensive. It becomes a replacement conversation only when water has been overflowing long enough to corrode the coil, rust the cabinet, or damage the blower, or when the system is already old enough that a bigger repair is stacking on top of it.

Condensate Pump and Drain Line Repairs: What They Cost

Nobody calls us about a condensate drain line. They call about a water stain on the ceiling, a puddle in the garage, or an air conditioner that shut itself off in the middle of a July afternoon in Kent. The drain line is the cause in a surprising share of those calls, and it is one of the few cooling repairs where the fix is cheap and the delay is expensive.

Here is the honest breakdown: what the condensate system does, what fails, what it costs across Puget Sound, and which part of it you can handle yourself.

What the condensate system actually does

When your system is cooling, the indoor coil runs colder than the air moving across it. Water vapor condenses on the fins and runs into a drain pan underneath. On a humid Western Washington afternoon, a working system can pull gallons of water out of your house per day. That water has to leave.

It leaves one of two ways:

By gravity. A PVC line slopes from the drain pan to the outdoors, a floor drain, or a standpipe. No moving parts, nothing to fail — until it clogs.
By pump. When the air handler sits below the drain exit, in a basement, a closet, or on a slab, a small condensate pump collects the water and pushes it up and out through vinyl tubing.

Both paths are quietly critical, and both are on the cheap end of the hardware in your mechanical room. That is exactly why they get ignored.

What actually fails

The drain line clogs

This is the number one cause. The drain pan is dark, wet, and fed by air that just passed through your house, so dust and biological slime build up at the trap or the first elbow. Once the line restricts, the pan backs up. Any system installed with a proper float safety switch shuts down at that point. Any system installed without one keeps running and overflows.

The pump dies

Condensate pumps are small mechanical devices living permanently in water. Five to ten years is a normal life. They fail by seizing, by losing the float, or by running continuously without moving water. A pump that hums but does not discharge is finished.

The line was never sloped right

We see this on installs where someone fought the framing instead of re-routing. A flat or back-pitched section of PVC holds standing water, and standing water grows the exact slime that causes clogs. This one clogs again every single season until the pipe gets rebuilt.

The discharge tubing kinks or freezes

A pump line routed through an unconditioned crawl space or pinched behind a water heater will stop moving water. Same result, different cause.

What condensate repairs cost in Puget Sound

Repairs on cooling equipment in this region run $150 to $1,500 in standard markets, $175 to $1,800 in affluent markets like Seattle, Normandy Park, Maple Valley, Black Diamond, Steilacoom, and Fircrest, and $200 to $2,000 in luxury markets like Bellevue, Gig Harbor, and Fox Island. Condensate work sits mostly at the bottom of those ranges. Here is how the common jobs stack up.

Repair	Where it lands in the range	Typical time
RepairClear and flush a clogged drain line	Where it lands in the rangeLow end	Typical timeUnder an hour
RepairAdd or replace a float safety switch	Where it lands in the rangeLow end	Typical timeUnder an hour
RepairReplace a condensate pump	Where it lands in the rangeLow to mid	Typical time1 to 2 hours
RepairRe-pipe a badly sloped drain line	Where it lands in the rangeMid	Typical time2 to 4 hours
RepairClear the clog plus clean a fouled coil	Where it lands in the rangeMid	Typical timeHalf a day
RepairDrain line plus water damage to the air handler	Where it lands in the rangeUpper end, or a replacement conversation	Typical timeVaries

The honest framing: on its own, this is one of the least expensive things that can go wrong with your air conditioning system. You get a price before any work starts, not after. What makes it expensive is ignoring it, because condensate that overflows for a week finds drywall, subfloor, and the electrical components inside the cabinet.

Why Puget Sound homes clog faster than you would expect

We are a mild, damp marine climate. People assume that means less condensate than Phoenix or Atlanta, and in total volume it often does. But two local factors work against the drain line:

Crawl space and garage air handlers. A huge share of homes here put the indoor unit in an unconditioned space where humidity, dust, and temperature swings all encourage biological growth in the pan.
Short, intense cooling seasons. A system that sits dormant from October to June develops a dried biofilm in the trap, then gets hit with a sudden heat stretch. The first big cooling week of the year is when the calls spike.

If your system only runs hard for a few weeks a year, the drain line gets inspected a few weeks a year. That is the gap.

The float switch is the cheapest insurance in your house

A float safety switch sits in the drain pan or on the drain line and cuts power to the system when water backs up. Your AC stops cooling. That is annoying on a hot day, and it is also the switch doing exactly its job — trading one uncomfortable afternoon for a ceiling you do not have to replace.

If your system shut off on its own during a heat stretch and you found water near the indoor unit, do not reset it and walk away. The water is still there. The same logic applies to any system that cuts out unexpectedly; our walkthrough on a system that stops producing covers the free checks worth doing before you call.

Not every older install has a float switch. Adding one is a low-end repair and it is one of the first things we recommend on any air handler sitting above finished space.

If your indoor unit is in an attic or above a finished ceiling and there is no float switch, fix that before you fix anything else. The pan is one clog away from your drywall.

What you can do yourself, and what to leave alone

Reasonable homeowner maintenance:

Change the air filter on schedule. Less dust at the coil means less sludge in the pan.
Pour about a cup of distilled white vinegar into the drain line access tee once or twice during cooling season. Skip the bleach — it is hard on pan materials and metal cabinet components.
Keep the area around the indoor unit dry and visible so you notice a problem early.
Check the pump's discharge tubing for kinks or crushed sections.

Leave this to a technician:

Pulling a wet-vac on the exterior drain termination without knowing where the trap is. You can pull the trap dry and get sewer gas or an air short-circuit instead.
Opening the air handler cabinet. Electrical and refrigerant components live in there.
Re-piping. Slope matters, and so does the trap depth relative to blower pressure. Done wrong, it drains backwards.
Diagnosing why the pan is overflowing when the line is clear — that usually points to an iced coil or a drain pan crack, which are different repairs.

When the drain problem is really a different problem

A few times a season we clear a line, run the system, and the pan fills again anyway. That means the clog was a symptom.

An iced indoor coil dumps far more water than the pan was designed for when it thaws. Low refrigerant charge or severe airflow restriction is usually behind it.
An oversized system short-cycles. It cools the air fast, shuts off before it dehumidifies properly, and leaves a damp coil sitting idle — good conditions for growth.
A rusted or cracked drain pan on an aging air handler leaks regardless of how clear the line is. On a system that is already a decade-plus old, that is where the repair-or-replace conversation starts, and we will show you both numbers side by side rather than steering you.

If your system is older and this is the third thing that has gone wrong in two seasons, the pattern matters more than the individual repair. That is true for cooling equipment the same way it is for heat pump repair and replacement decisions.

Getting a real number

Condensate work is scheduled service, not a guessing game. Describe what you are seeing — water location, whether the system shut itself off, where the indoor unit sits — and we can usually tell you on the phone whether this is a one-hour visit or something bigger.

Want pricing on a bigger project while you are at it? The instant estimate tool gives you Good, Better, and Best starting prices in about 60 seconds, and a free in-home estimate confirms the real number against your actual equipment. Call (253) 785-4622, Monday through Friday, 8 to 6. We serve 45 cities across King, Pierce, Thurston, and Kitsap counties from our shop in Federal Way, and every installation we do carries a 10-year parts and labor warranty.

Local utility rebates may apply on equipment replacements — the amount depends on what is being replaced and the equipment installed. Programs change, so we read the utility off your bill, confirm what it actually pays, and file the paperwork. Rebates do not apply to a drain line clear, and we are not going to pretend otherwise.