Dishwasher Not Draining in Exeter - What to Check and What to Do

Published July 2026 | Dishwasher Not Draining

What Causes a Dishwasher to Stop Draining

Standing water in the bottom of your dishwasher is one of the most common appliance faults our engineers attend across Exeter and the wider Devon area. The good news is that the cause is usually something mechanical and identifiable - not a sign that the whole machine needs replacing.

There are several typical culprits worth understanding before you start poking around.

A blocked or clogged filter is the number one cause. Every dishwasher has a filter system at the base of the tub that catches food particles. When this becomes clogged, water can't pass through quickly enough and sits at the bottom. Brands like Bosch, Hotpoint, and Beko all use variations of this design, though how easy the filter is to remove varies between models.

A kinked or blocked drain hose is the second most common cause. The drain hose runs from the pump to either your sink trap or a dedicated waste connection. If it's been pinched behind a unit, filled with grease build-up, or installed without the right high-loop arrangement, water backs up into the machine rather than draining away.

A faulty drain pump becomes the likely cause when the filter and hose are clear but water still won't shift. The drain pump is an electric motor with an impeller that forces water out of the machine. When the impeller breaks, gets jammed with glass or debris, or the motor burns out, drainage stops completely. This is a common issue in older LG and Samsung machines but it can happen to any brand.

A blocked sink trap or waste connection is often overlooked. If your dishwasher drains into the sink's waste system and that trap is blocked, water has nowhere to go. This is especially common if you've recently had a kitchen sink blockage alongside the dishwasher problem - the two issues are often related.

A faulty check valve can also be responsible. This small component sits inside the drain hose or pump assembly and stops water from flowing back into the machine after draining. When it fails, water flows back in, leaving you with standing water even though the machine drained fine mid-cycle.

Control board or door latch faults are less common but worth knowing about. Some dishwashers won't complete a drain cycle if the door latch sensor fails or the control board develops a fault. You may notice other symptoms alongside the drainage problem, such as error codes on the display or programme lights that don't respond correctly.

How to Diagnose a Dishwasher That Won't Drain

Before calling out an engineer, it's worth working through these checks yourself. Many Exeter homeowners find the issue and resolve it without spending anything.

Step 1 - Switch off and unplug the machine. Before you put your hands anywhere near standing water inside an appliance, isolate it from the mains. Pull the plug from the socket or switch off the dedicated circuit at the fuse board.

Step 2 - Remove any standing water manually. Use a cup or a turkey baster to scoop out the water, then soak up the remainder with old towels. You need to see the floor of the tub clearly before you can check the filter properly.

Step 3 - Locate and remove the filter. On most machines, the filter sits at the very bottom of the tub, often near the back. It typically consists of a cylindrical mesh filter that unscrews and a flat mesh plate beneath it. Refer to your machine's manual if you're unsure - Bosch and Siemens machines, for example, require a quarter turn to release the filter. Rinse it thoroughly under a warm tap. If it smells bad and looks like it hasn't been cleaned in months, that's very likely your problem.

Step 4 - Check the sump area beneath the filter. With the filter removed, look into the sump - the well at the base of the tub. Use a torch. Look for broken glass, food debris, a stray piece of plastic, or anything that could be jamming the pump impeller. A small fragment of crockery getting through a damaged filter and jamming the pump is one of the most common causes we find in Exeter call-outs.

Step 5 - Run a short cycle and observe. Replace the filter, restore power, and run the shortest cycle available. Watch whether the machine starts to drain at all. Can you hear the pump motor trying? A humming sound with no drainage often points to a jammed or failed pump. No sound at all can suggest an electrical or control fault.

Step 6 - Check the drain hose. Pull the dishwasher forward carefully and inspect the drain hose at the back. Look for kinks, cracks, or obvious blockages. If the hose connects directly to the sink trap, disconnect it carefully and check whether the trap itself is clear. Run water down the sink to confirm it flows freely before reconnecting everything.

Step 7 - Check for error codes. Modern dishwashers from Bosch, Samsung, LG, and other manufacturers display error codes when there's a drain fault. Common drain-related codes include E24 on Bosch machines and OE on LG models. Look the code up in your manual or enter it into the Voltrade GoFIX diagnostic tool - it can help narrow down whether you're looking at a mechanical blockage, a pump fault, or something electronic, and point you towards the right next step.

DIY or Professional - When to Call an Engineer

Knowing when to stop and call a professional is as important as knowing what to check yourself. Here's a clear breakdown.

You can handle it yourself if:

• The filter was visibly clogged and cleaning it resolves the problem
• The drain hose was kinked and straightening it fixed the drainage
• The sink trap was blocked and clearing it sorted the issue
• The machine runs cleanly after you removed debris from the sump area

Call a qualified engineer if:

• The filter is clean, the hose is clear, but water still won't drain
• You can hear the pump humming but nothing is moving - this usually means a jammed or failed pump impeller
• The machine is showing persistent error codes that don't clear after basic checks
• There's any sign of water leaking underneath the machine during the drain cycle
• The machine is tripping the circuit breaker, which can indicate a motor or wiring fault
• The machine is still under warranty - opening up the pump housing yourself may void it

As a rule of thumb, filter cleaning and hose checks are well within most people's ability. Anything involving the pump, the wiring, or the control board needs someone with the right tools and knowledge. Our engineers cover Exeter and surrounding Devon towns and can typically diagnose drain faults within the first 15 to 20 minutes of a visit.

What a Qualified Appliance Engineer Will Do

When one of our engineers attends a drainage fault, they follow a structured diagnostic process rather than just replacing parts and hoping for the best.

They'll start by confirming the basics - running a drain cycle, listening to the pump motor, and checking whether the machine responds to commands correctly. They'll use diagnostic modes where available. Many modern dishwashers, including Bosch and Miele models, have a built-in service mode that runs individual components in sequence so the engineer can isolate exactly where the fault lies without unnecessary guesswork.

If the pump motor is suspected, the engineer will measure resistance across the motor windings with a multimeter. A failed motor will show an open circuit reading. If the impeller is jammed, they'll disassemble the pump housing carefully, extract whatever's causing the blockage, and check whether the impeller blades are damaged. In many cases the impeller can be cleared rather than replaced, saving you the cost of a new part.

If the drain pump does need replacing, they'll source a compatible part. Many common pumps - including those used in Hotpoint, Indesit, and Beko machines - are shared across product ranges, which makes parts availability generally good in the UK. Genuine manufacturer parts typically cost more than compatible alternatives, and the engineer will advise on which option makes most sense for the age and value of your machine.

For control board faults or check valve failures, the approach is the same - test, confirm, replace with the correct part. A professional visit should always end with a full test run to confirm the drainage is working correctly before the engineer leaves.

Costs and What Affects the Price

Appliance repair costs in Exeter follow a similar pattern to the rest of the South West, though they vary depending on the engineer and the complexity of the fault.

Call-out and diagnostic fee: Most local engineers charge a call-out fee covering the visit and initial diagnosis. This typically sits between 50 and 80 pounds. Some services include this within a fixed diagnostic charge; others apply it to the total cost if you go ahead with the repair.

Simple blockage clearance: If the engineer attends and finds a blocked filter or a jammed pump that can be cleared without new parts, the total cost is typically between 60 and 100 pounds including the call-out.

Drain pump replacement: This is the most common repair for persistent drainage faults. Parts vary in cost depending on the brand and whether you use genuine or compatible components. A drain pump for a Bosch or Siemens machine typically costs between 40 and 80 pounds for the part alone. Labour to fit it is usually 40 to 60 pounds on top. Total cost for a drain pump replacement therefore commonly falls between 80 and 150 pounds all in.

Control board replacement: This is a more expensive repair. Control boards for brands like LG or Samsung can cost between 100 and 250 pounds for the part alone, making total repair costs potentially between 150 and 350 pounds. At that level, it's worth comparing the repair cost against the price of a new entry-level dishwasher, which typically starts around 250 to 300 pounds for a basic freestanding model.

What pushes the price up: The age of the machine matters - parts for older models can be harder to source and may cost more. Brand also plays a role; parts for premium brands like Miele tend to cost significantly more than those for Beko or Hotpoint. Location within Devon can affect travel costs if you're well outside Exeter.

A useful general guideline: if a repair is going to cost more than half the replacement value of the machine, and the dishwasher is more than eight years old, it's usually worth replacing rather than repairing.

How to Prevent Drainage Problems in Future

Drainage faults are among the most preventable appliance issues. A few simple habits will keep your machine draining reliably for years.

Clean the filter every month. This is the single most effective preventative step. Remove the filter, rinse it under warm running water, and use a soft brush to scrub any debris from the mesh. It takes about two minutes. Manufacturers including Bosch, Hotpoint, and Beko all recommend monthly filter cleaning in their user guides - it's consistently the most ignored advice we come across in Exeter.

Scrape plates before loading. You don't need to pre-rinse plates thoroughly, but you should scrape off large food particles. Rice, pasta, and leafy greens are particularly effective at clogging filters and blocking pump impellers over time.

Run a hot maintenance wash monthly. Run an empty cycle at 65 or 70 degrees with a dedicated dishwasher cleaner, or place a cup of white vinegar upright on the bottom rack. This clears grease build-up from the hose and pump housing before it becomes a full blockage.

Use the correct amount of rinse aid and dishwasher salt. In hard water areas across Devon and Exeter, limescale can build up inside the pump and spray arms over time, restricting flow. Keeping the salt dispenser topped up protects the machine's internal components from scale deposits.

Check the drain hose position after moving the machine. If you've had kitchen work done, pulled the dishwasher out for any reason, or had a new kitchen fitted, confirm the drain hose is back in the correct high-loop position - ideally secured above the level of the sink trap connection. This prevents backflow and slow drainage developing over time.

Act on early warning signs. If you notice the machine is taking longer to drain than usual, or there's a small amount of residual water after a cycle, address it before it becomes a full blockage. A maintenance wash and filter clean at the first sign of slow drainage can save you a repair visit entirely.

Frequently Asked Questions

Why is there always a small amount of water at the bottom of my dishwasher?

A small amount of water in the very bottom of the tub - around a cup's worth - is completely normal on many machines. It's intentional and there to stop the door seal from drying out and cracking between washes. If there's significantly more than that, or water is pooling above the level of the filter, that's a drainage fault and worth investigating. Start by cleaning the filter and checking the drain hose.

Can I keep running my dishwasher if it won't drain properly?

It's not a good idea. Running a machine with a drainage fault can cause water to overflow onto your kitchen floor, potentially damaging your flooring and the units underneath. It can also put extra strain on the drain pump motor, turning a relatively minor fault into a more expensive repair. Switch the machine off, identify the cause, and resolve it before running another cycle.

How long does a dishwasher drain pump typically last?

In most cases, a drain pump will last somewhere between seven and twelve years with normal use. How long it actually lasts depends on how often the machine runs, how consistently the filter is maintained, and whether debris has been allowed to pass through to the pump housing over time. Machines run regularly with a dirty filter tend to develop pump faults earlier than well-maintained ones.

Is it worth repairing an older dishwasher that won't drain in Exeter?

It depends on the age of the machine and the cost of the repair. If the dishwasher is under eight years old and the repair is going to cost less than 150 pounds, repair is usually the more economical choice. For machines over ten years old, or where the repair cost is approaching the price of a new replacement, investing in a new machine often makes more financial sense. One of our Exeter engineers can advise you on this after diagnosing the fault - there's no obligation to proceed with a repair if the numbers don't stack up.

Do appliance engineers in Exeter carry dishwasher parts with them?

Most experienced appliance engineers carry commonly used parts - drain pumps, door seals, and standard components for popular brands like Bosch, Hotpoint, Beko, and Indesit. Parts for less common models or premium brands like Miele may need to be ordered in, which can add a few days to the repair timeline. When booking, let the engineer know the make, model number, and the fault you're experiencing so they can check parts availability in advance.