A puddle of water spreading under the dishwasher or at the foot of the counter is never trivial. Before attempting an improvised teardown, here’s how to identify the source of the problem and determine whether professional help is needed.

The most common causes of a leak

According to data collected by our technicians during leak-related service calls, five causes come up most often and account for more than 8 out of 10 leaks on their own:

  • The drain hose (about 3 leaks out of 10): the most common cause. A loose fitting, a crack, or wear on the hose carrying wastewater to the drain is enough to cause a continuous leak.
  • The door seal (nearly 1 leak out of 4): a worn, hardened, or dirty seal no longer seals the door properly, and water escapes from the front during the cycle.
  • The drain pump (nearly 1 leak out of 5): a failed seal, or an object caught inside (a small piece of dishware, a label, a toothpick), can prevent it from working properly and cause a leak.
  • The filter (about 1 leak out of 20): when clogged, it causes water to overflow instead of circulating properly.
  • The water inlet valve (about 1 leak out of 20): a valve that stays partially open lets water through even outside of cycles.

What you can check yourself

  • Pinpoint exactly where the water is coming from: the front (door) or underneath/behind the appliance. This alone narrows down the diagnosis considerably.
  • Inspect the door seal for cracks or residue, and clean it with a damp cloth.
  • Check that the appliance is properly levelled. A poorly levelled dishwasher can leak from the door even if the seal is in perfect condition. See our installation guide for what to check.
  • Clean the filter regularly: it’s one of the most overlooked maintenance steps. Our article on dishwasher odors explains how and how often to do it.
  • If accessible without disassembly, check the visible fittings under the sink or behind the appliance.

When to call a repair technician

  • The leak comes from underneath or behind the appliance (pump, drain hose). These areas aren’t safely accessible without disassembly.
  • The leak persists despite cleaning the door seal and filter.
  • Water leaks even when the appliance is off, between cycles. This is a likely sign of a faulty water inlet valve. Shut off the water supply valve under the sink while waiting for service: water damage is among the most frequent and costly residential claims in Canada, so it’s best to act before it gets worse.
  • The leak is accompanied by an electrical issue (burning smell, sparks, a tripped breaker). Water and electricity don’t mix, don’t take any chances.

A leak coming from an inaccessible area, or one that persists despite your checks? Our technicians, trained on all brands, serve Laval, Montreal and the greater Quebec City region, with a one-year warranty on every repair performed. Submit a service request.

FAQ

Can a dishwasher with a small leak wait to be repaired?

No. Even a minor leak can signal a seal or hose on the verge of complete failure, and water seeping under the appliance or into the floor can cause damage far more costly than the repair itself.

Can I repair a door seal myself?

Cleaning it, yes. Replacing the seal generally requires removing the door panel and installing the correct original part for your brand and model, a step where professional help avoids unpleasant surprises.

In Summary

Most dishwasher leaks come from the drain hose, the door seal, or the drain pump. Proper levelling and a clean filter prevent a good share of cases, but as soon as the leak comes from an inaccessible area or persists despite your checks, it’s best to call a professional before the water damage gets worse.