Dishwasher Problems: When to DIY and When to Call an Engineer

A dishwasher that stops cleaning properly, smells off or makes a racket isn't always a job for an engineer. Plenty of common gripes come down to simple maintenance you can sort out yourself in twenty minutes. The trick is knowing which problems are quick fixes and which point to a fault in the pump, motor or electrics that needs proper attention.

This guide walks you through the difference, with a step-by-step on the single most useful bit of dishwasher upkeep there is: cleaning the filter. If your machine is still struggling once you've worked through it, that's usually the moment to book a dishwasher repair rather than keep guessing.

Start with the filter (most problems begin here)

The filter does the heavy lifting in any dishwasher. Its job is to trap food particles and debris washed off your plates so they don't clog the spray arms and pump. When it gets blocked, the knock-on effects show up fast, and many people assume the machine is broken when it just needs a clean.

Here's what a neglected filter tends to cause:

• Poor cleaning performance. A clogged filter restricts water flow inside the machine. Dishes come out badly rinsed, with food residue and stains left behind.
• Unpleasant odours. Trapped food becomes a breeding ground for bacteria, creating foul smells that can transfer onto your dishes so they smell and taste off.
• Damage to the dishwasher. When water can't circulate freely, the pump and motor work harder. Over time that extra strain wears out critical components and can lead to expensive repairs.
• Hygiene concerns. Without proper cleaning and rinsing, harmful bacteria and pathogens may not be removed from your dishes during the cycle.
• Higher energy and water bills. A struggling machine runs longer to get dishes clean, wasting both electricity and water.

The good news is that all of this is preventable with a regular clean.

How to clean your dishwasher filter

Most dishwashers use one of two filter types: a cylindrical filter, a fine mesh filter, and some models have both. Whichever yours has, the process is much the same.

Safety first: unplug the dishwasher or disconnect it from the power supply before you start. If you want a refresher on doing this properly, see our guide on how to safely isolate an appliance before a DIY repair.

1. Consult the manual. Check your user manual to find the filter and read any specific instructions from the manufacturer.
2. Prepare your workspace. Lay down a towel or mat to catch water and debris, and pop on a pair of gloves to keep your hands clean.
3. Open the door fully. The filter usually sits at the bottom of the dishwasher, near the spray arm.
4. Remove the lower rack. Sliding it out gives you much easier access.
5. Identify the filter. Locate the filter assembly, which may be cylindrical, fine mesh, or both.
6. Remove the filter assembly. Depending on the model, it will either twist or lift out. Follow the manufacturer's instructions and go gently, as there may be dirty water trapped inside.
7. Clean the filter. Take it to the sink and rinse under warm running water. Use a soft brush or an old toothbrush to lift any stubborn residue, making sure every part is properly clean.
8. Inspect and clean the housing. While the filter is out, check the filter housing inside the machine and clear away any food particles that have built up.
9. Reassemble the filter. Refit the assembly according to the manufacturer's instructions and make sure it's locked securely in place.
10. Replace the lower rack. Slide it carefully back in.
11. Close the door. Shut it securely.
12. Run a test cycle. Put a short, empty cycle through to confirm everything's working as it should.

Do this at least once a month, or more often if you notice your dishwasher's cleaning dropping off. It takes minutes and saves a lot of bother.

What you can safely tackle yourself

Alongside the filter, a few jobs sit firmly in the DIY camp:

• Cleaning the filter and the filter housing
• Checking the spray arms (remember, a clean filter is what stops them and the pump clogging in the first place)
• Reviewing how you load the machine so water can reach everything

These are maintenance tasks, not repairs. They don't involve opening up the machine or touching wiring, and they fix a surprising number of complaints about dirty dishes and odd smells.

When it's time to call an engineer

If your dishwasher is still underperforming after you've cleaned the filter, something else is going on. Some faults need testing tools and trained hands, and trying to bodge them can make things worse or unsafe.

Call a professional for:

• Pump faults
• Motor faults
• Leaks
• Electrical faults
• Persistent underperformance after the filter has been cleaned

The everyday symptoms that usually trace back to these include dishes remaining dirty despite a clean filter, a door that won't close, water leaking onto the floor and excessive noise during a cycle. A local NAC technician can assess what's actually wrong and carry out a dishwasher repair if one's needed.

How NAC repairs work

We keep the costs straightforward. Before an engineer attends, we quote a service charge that covers all labour, the callout and VAT where it applies. The only thing that might be added is parts, and if any are needed we'll quote those separately and get your go-ahead before any work happens. There's no extra labour charge on top, it's all included in that initial service charge.

Every repair comes with a guarantee, too. The exact length depends on the parts fitted and is set out in our terms and conditions, so you've got peace of mind once the job's done.

NAC is a family-run business. Husband and wife team Adrian and Amanda set the standards here, drawing on over 40 years of experience, and our engineers are fully trained by us across all the makes and appliances we work on. We aim to send someone out the same day you report a fault, or the next day where possible.

Book your dishwasher repair

If a clean filter hasn't solved it, don't keep running a machine that's struggling, since that only puts more strain on the pump and motor. Get in touch with NAC or call 0333 016 9622 to book your dishwasher repair appointment, and we'll get it sorted properly.

Want to keep on top of your other appliances too? Our help section has practical guides like how to clear a blocked fridge drain hole and a cooker hood maintenance checklist to keep things running smoothly around the kitchen.