Dishwasher Leaking? 7 Places to Check and Fix

A dishwasher leaking onto the kitchen floor is worth acting on the same day, because even a slow drip can soak the cabinet base and lift flooring before you notice. The good news is that the source is usually one of seven places, and a dry-towel test finds it in about fifteen minutes.

Before anything else, stop the cycle, switch off the breaker for the dishwasher, and mop up. Standing water around a plugged-in appliance is not a place for bare feet. Once the floor is dry and the power is off, you can start looking.

The dry-towel test for a dishwasher leaking

Pull the bottom rack out, dry the tub and the floor around the machine, and lay dry towels or paper sheets in front of it and, if you can see it, under the front panel. Run a short cycle with the power back on, stopping to check the towels every few minutes through the fill, wash, drain and rinse stages. Note when the puddle appears:

• At the start, while the machine fills: think inlet valve, water supply line or door seal.
• During the wash: think spray arm, door gasket, or too many suds.
• During drain: think drain hose, clamps or the sink connection.
• Only when the door is opened mid-cycle: that is normal splash and not a fault.

Where the water shows up matters as much as when with a dishwasher leaking. Water at the front edge of the door points to the gasket, latch or spray arm. A puddle toward the back or underneath points to hoses and the pump. If the cabinet under the sink is wet, check the supply line and the drain connection there too.

7 places to check when a dishwasher is leaking

Work through these in order whenever you find a dishwasher leaking. The first four need no tools.

1. The door gasket. Run a finger around the rubber seal. If it is cracked, flattened, torn or covered with grime, water slips past. Wipe it with warm water and check that it sits fully in its groove.
2. The spray arms. A cracked or loose arm, or one blocked by a bit of glass or a toothpick, sends water against the door. Spin each arm by hand and look for cracks.
3. Dish loading. A tall pan or platter that sticks into the spray path, or a handle that blocks the door from latching, can cause a leak that is not a defect.
4. Soap and suds. Hand dish soap in a dishwasher foams and pushes water out around the door. Use a detergent made for the machine. If it has happened, run an empty rinse and wipe the tub.
5. Door latch and hinge. A door that does not close squarely or a worn latch keeps the gasket from sealing.
6. Hoses, clamps and the water inlet valve. Check the fill line, the drain hose and the clamps. A loose clamp, a worn hose or a weeping inlet valve leaks at the back or underneath.
7. The tub, pump or float. A cracked tub, a worn pump seal or a stuck float switch can let water out or let the machine overfill. These are technician jobs.

Sorting a dishwasher leaking from the front from one at the back

A dishwasher leaking from the front is usually the cheaper kind: gasket, loading, suds or spray arm. Leaks from underneath are more serious, because the water has traveled from a hose, a pump or the tub. If you see rust at the base of the tub or water pooling after the machine has been off, treat it as a leak that needs a professional, not a cleaning fix.

If a leak followed a recent hookup or a moved machine, the problem may be the install. Our article on dishwasher installation lists the connections to look at, including the drain loop.

Water damage risk from a dishwasher leaking

A slow leak is the one that costs the most, and a dishwasher leaking a little each cycle is easy to ignore. Water travels under the dishwasher, into the subfloor and the cabinet base, and chipboard cabinets swell and fail. Signs of earlier damage include a soft or springy floor in front of the machine, lifting laminate, a musty smell under the sink or a stain on the ceiling below the kitchen in a two-story home.

Until the source is found, do not run a dishwasher leaking water. If you cannot find the leak, close the water supply valve under the sink as well. That valve is usually a small quarter-turn or a screw-type stop near the supply line. Place a tray under the machine if the leak continues when it is off.

If the water came from the dishwasher’s supply line and keeps running when the machine is off, close the valve and call someone. Do not try to repair a pressurized line with tape.

When to stop and call us about a dishwasher leaking

Stop and book a repair if the leak shows up at the back or underneath, if the breaker trips or the control panel is wet, if the floor is soft, or if the tub is cracked or rusted through. The same goes if the dishwasher keeps leaking after you have cleaned the gasket, changed the soap and checked the loading. Switch off the breaker before anything else and keep the power off until the water source is found, since the wiring sits near the bottom of the machine.

Never bypass the float switch or any safety device to keep a leaking dishwasher running. Those switches are there to stop a flood. A dishwasher leaking past a failed float should not be used until it is repaired.

If the leak points to the machine’s age or cost, use the appliance diagnosis tool to narrow it, then think about whether the unit is worth the repair.

What we do when we arrive

For a dishwasher leaking in West Sacramento, Sacramento, Davis, Woodland or the rest of our service area, our technician comes to your home in a marked vehicle and offers to wear shoe covers. The tool bag and the troubleshooting schematics come with them, along with common parts, so many leaks are fixed the same day. We look at the gasket, spray arms, hoses, valve, pump and tub, and tell you the repair price after looking. You can read more on our dishwasher repair page.

Many people ask whether a dishwasher leaking is the machine or the sink plumbing. A quick check is to look under the sink with a flashlight and run only the kitchen tap. If the pipes stay dry, the dishwasher is the suspect.

The ENERGY STAR dishwasher guidance is useful if you are considering a newer unit. If your dishwasher leaking problem is still unsolved, book a visit and we will find the source. The service call is $80.

Common questions

Is a leaking dishwasher dangerous to use?

Using it risks water on the floor and near the wiring at its base, plus hidden damage to the cabinet and subfloor. Switch off the breaker, mop up and keep the power off until the source of the leak is found.

Can too much detergent make a dishwasher leak?

Yes, especially regular dish soap. It foams, and suds push water out around the door. Use dishwasher detergent in the right amount, run an empty rinse after an incident, and wipe the gasket before the next load.

How do I know if the leak is the dishwasher or the sink?

Run only the kitchen tap and check under the sink with a flashlight. If everything stays dry, run a dishwasher cycle with dry towels around it and watch when the puddle appears. The timing points to the cause.