Opening the dishwasher to find a puddle of dirty water sitting in the bottom is a frustrating way to end a cycle, but it is one of the most common faults we see, and one of the most fixable. A dishwasher that won’t drain is almost always a mechanical blockage or a tired pump rather than a machine that’s on its last legs, so before you start pricing up a replacement, it’s worth understanding what’s actually going on. Here’s what usually causes it and what you can safely check yourself.
The most common reasons a dishwasher won’t drain
A blocked filter
The filter in the base of the tub catches food scraps, grease and the odd bit of broken glass so they don’t reach the pump. Over months of use it clogs up, and once water can’t get through it, the machine can’t drain. This is the single most common cause we find, and on many models it’s a part you can lift out and rinse yourself.
A blocked or kinked drain hose
The drain hose carries waste water out to your sink’s waste trap or a standpipe. It can clog with grease and debris over time, or get kinked behind the machine, especially if the dishwasher has been pulled out and pushed back at some point. A partial blockage here often shows up as slow draining before it stops altogether.
A failed drain pump
If the filter and hose are clear, the drain pump itself may have failed or become jammed. Small items like fruit stickers, a chip of glass or a stray toothpick can foul the pump impeller and stop it turning. Sometimes it’s a genuine motor failure. Either way, this is where a proper on-site diagnosis pays off, because we can test the pump rather than guess at it.
A waste trap or garbage disposal issue
Because the dishwasher usually drains into the same plumbing as your kitchen sink, a blocked sink waste trap can back water up into the machine. If your sink is draining slowly too, that’s often a clue the problem is in the plumbing rather than the dishwasher itself.
A control or leak-sensor fault
Less often, a dishwasher that won’t drain is throwing an error or has tripped its leak sensor, which can hold water in the tub as a safety measure. Door-latch faults and control-board issues can present the same way. If you’re seeing an error code or the machine won’t start its drain cycle at all, that points to the electronics rather than a blockage.
What you can safely check yourself
- Turn it off at the wall before you put your hands anywhere near the machine. Never work on a dishwasher that’s still switched on.
- Bail out the standing water with a cup and a sponge so you can see and reach the base of the tub.
- Remove the bottom rack and lift out the filter (usually a twist-and-lift cylinder in the base), then rinse it under a hot tap and clear anything caught underneath.
- Check the sink your dishwasher drains into. If it’s draining slowly, run some hot water and clear the sink waste trap.
- Look behind the machine for an obvious kink in the drain hose, and make sure it hasn’t been squashed against the wall.
- Run a short cycle and watch whether it drains. If it still holds water, it’s time for a technician.
When to call a technician
If you’ve cleared the filter, checked the hose and the sink still drains fine but the dishwasher won’t, the problem is most likely the drain pump or the electronics, and that’s where a professional dishwasher repair is the sensible next step. We test the pump, read any error code and check the whole water path so the real fault gets fixed, not just the part that looks worn. We can usually fix the fault on-site, so most jobs are sorted in a single visit; if a part is needed to match your model, we quote it first before ordering.
Our call-out fee is $100 for jobs close in across the Illawarra, or $150 for further out, and it covers travel and inspecting your dishwasher. If we can fix it on the spot without parts, there’s a flat $50 labour fee. If parts are needed we quote you first, and that $50 is credited toward the total repair. No overtime or after-hours surcharges.
We come to you across Wollongong, Shellharbour, Kiama and the wider Illawarra & Shoalhaven, so there’s no need to wrestle a heavy machine out of the kitchen. You can book a repair online any time, or give us a call on (02) 4288 2824 and we’ll find you the earliest slot.
