Dishwasher Not Cleaning Properly What to Check in Addlestone

Published September 2026 | Dishwasher not cleaning properly what to check

This guide walks you through the most common reasons a dishwasher stops cleaning properly and how to check each one yourself at home. It's aimed at homeowners in Addlestone and the surrounding Surrey area who want to diagnose the problem before spending money on a call-out.

Before You Start - Safety First

Before you touch anything inside or underneath your dishwasher, switch it off at the wall socket and unplug it. This isn't optional. Even when a dishwasher isn't running, there's residual water sitting in the sump and electrical components that can pose a risk if you start probing around without isolating the power first.

A few other things worth knowing before you begin:

• If you can smell burning plastic or see scorch marks inside the machine, don't investigate further yourself. Switch off and call an engineer.
• If your dishwasher is throwing up an error code on the display (common on Bosch, Samsung and LG models), photograph it before you reset the machine. That code tells a technician a lot about what's gone wrong.
• Water and electricity are a dangerous combination. If the floor around the machine is wet and you're unsure why, step back and get professional help rather than kneeling down to look.
• Keep children and pets out of the kitchen while you're working. Dishwasher filters and spray arms have sharp edges.

With those precautions in place, most of what follows is well within what a careful homeowner can handle themselves.

What You Will Need

You don't need specialist tools for most of these checks. Here's what to have on hand before you start:

• A soft cloth or sponge
• An old toothbrush (essential for getting into filter mesh and spray arm holes)
• White vinegar (cheap, effective for descaling)
• A dishwasher cleaning tablet or powder - Finish Quantum or Fairy Platinum both work well
• A torch or your phone's torch function
• A flathead screwdriver
• Replacement dishwasher salt and rinse aid if you're running low
• A replacement filter if yours turns out to be beyond cleaning - these typically cost between 8 and 20 pounds depending on the brand

Time estimate: Allow 30 to 45 minutes to work through all the checks below. If you find the filter is completely blocked and needs a thorough soak, add another 30 minutes for that alone.

Step-by-Step Instructions

Step 1: Clean the Filter

The filter is the single most common cause of poor cleaning results, and it's the first thing our engineers check when attending a job in Addlestone. It's located at the bottom of the dishwasher tub, usually in the centre or towards the back. On most machines - Hotpoint, Bosch, Beko and others - it twists out anticlockwise and lifts free in two parts: a coarse mesh cylinder and a flat fine filter beneath it.

Rinse both parts under the hot tap. Use your toothbrush to scrub the mesh thoroughly. You're looking for grease build-up, food debris, broken glass fragments and limescale. In hard water areas like much of Surrey, limescale is a particularly common culprit - a 20-minute soak in white vinegar will break it down where scrubbing won't. Once clean, reassemble and click it firmly back into place. A filter that's only partially seated will let debris recirculate through the wash cycle.

Step 2: Inspect and Clear the Spray Arms

Your dishwasher has at least two spray arms - one at the bottom and one mounted beneath the upper rack. Some machines have a third at the top of the tub. These arms spin during the wash cycle and jet water onto your dishes. If the holes along the arms are blocked with food or limescale, water can't reach everything in the load.

Pull each arm free - most clip off without tools, though some older Hotpoint models need a screwdriver. Hold each arm up to the light and look through each hole. Blocked ones will be clearly narrowed or sealed entirely. Use a cocktail stick or toothpick to clear the holes, then rinse the arms under the tap. Before refitting, spin them by hand to check they rotate freely on their mountings. A spray arm that wobbles or won't spin properly needs replacing - new ones typically cost between 10 and 30 pounds for most brands.

Step 3: Check the Detergent Drawer

Open the detergent drawer and look closely at the dispenser compartment. A drawer that doesn't open properly during the wash cycle means your detergent is sitting unused for most of the programme. The spring-loaded lid on the main compartment can fail over time, particularly on older machines. Test it by hand - it should snap open cleanly with light pressure.

Also check whether detergent residue has built up inside the drawer itself. A caked-up drawer restricts how much detergent gets into the wash. Clean it out with warm water and your toothbrush. If you've been using pods or tablets, make sure you're placing them correctly in the main compartment, not the pre-wash section. Placing a tablet in the wrong section means it dissolves too early and washes away before the main cycle begins.

Step 4: Check Salt and Rinse Aid Levels

In Surrey's moderately hard water zones, dishwasher salt is not optional - it's what keeps the water softener inside the machine functioning. Without it, limescale builds up on the heating element and inside the spray arms, and your dishes come out with a white, chalky film.

The salt reservoir is at the bottom of the tub, accessed by unscrewing a cap (usually on the left-hand side). Top it up with dedicated dishwasher salt - not table salt, which has additives that can damage the softener unit. The rinse aid reservoir is inside the door. Check the indicator window or light on your machine. Running low on rinse aid is a very common reason dishes come out streaky or spotted even when they're technically clean. Top both up and run a full cycle before deciding whether the problem persists.

Step 5: Review How You're Loading the Machine

Loading a dishwasher sounds obvious, but poor loading is responsible for more "dishwasher not cleaning" complaints than most people realise. Our engineers hear about this regularly from customers across Addlestone and the wider area. The main issues to watch for:

• Tall items in the lower rack blocking the upper spray arm from spinning
• Bowls and cups loaded right-side up so water pools in them rather than draining off
• Pots and pans stacked so tightly that water can't get between them
• Cutlery basket loaded with spoons nested together, which prevents water reaching the surfaces that need cleaning
• Large items like chopping boards placed at the front of the lower rack, blocking the detergent drawer from opening fully

Try a half-load with everything well-spaced and run a cycle to see if the results improve. It's a quick way to rule out loading as the issue.

Step 6: Check the Water Temperature

Dishwashers need hot water to clean effectively. Most cycles run at 55 to 65 degrees Celsius, and an eco cycle typically runs cooler - around 45 to 50 degrees. If your machine's heating element is starting to fail, the water won't get hot enough to cut through grease regardless of what detergent you use.

You can do a rough check by running a short cycle and carefully opening the door mid-wash (on machines that allow this). The steam and heat you feel should be significant. If the water inside feels only lukewarm, a failing heating element is a likely diagnosis. On a machine like a Samsung or LG with a digital display, an error code related to heating will often appear before you notice cleaning problems - another reason to note any codes you see.

Step 7: Run a Hot Maintenance Wash

If the machine is mechanically sound but results are still poor, a maintenance wash often clears the problem. Load nothing into the machine. Place a dishwasher cleaning tablet or a cup of white vinegar in the bottom of the tub. Select the hottest, longest programme available on your machine - typically a 70-degree intensive cycle. Let it run to completion.

This clears grease and biofilm from internal pipes, the sump and the heating element. Our engineers recommend doing this once a month as standard practice, particularly in older homes in Addlestone where limescale is an ongoing issue. After the maintenance wash, run a normal load and compare the results.

What to Do If This Does Not Fix It

If you've worked through all seven steps and the machine still isn't cleaning properly, the problem is likely mechanical rather than maintenance-related. The most common underlying faults at this point are:

• Pump failure: The circulation pump pushes water through the spray arms. A weak or failing pump means insufficient water pressure regardless of how clean your spray arms are. You may notice the machine sounds different - quieter than usual, or with a faint humming rather than the normal spray noise.
• Heating element failure: Confirmed if water remains cold throughout the cycle. This is a relatively common fault on machines over five years old.
• Control board issues: Intermittent cleaning problems that don't follow a pattern can point to a control board fault, particularly on Samsung and LG models. These are harder to diagnose without diagnostic equipment.
• Water inlet valve: If the machine isn't filling to the correct level, it won't clean effectively. A partially blocked or failing inlet valve can cause this.

If you're not sure which of these applies, the Voltrade GoFIX diagnostic tool can help you narrow it down before booking an engineer. Enter your appliance make, model and the symptoms you're seeing, and it'll give you a likely fault category and estimated repair cost - useful for deciding whether a repair makes sense versus replacing the machine.

When to Stop and Call a Professional

Some dishwasher faults are not worth attempting yourself, and pushing further can make things worse or create a safety risk. Call a qualified appliance repair engineer if you notice any of the following:

• A burning smell or visible scorching inside the tub
• The machine tripping the circuit breaker when it runs
• Water leaking from the base of the unit
• An unresolved error code after you've cleared and restarted the machine
• No water entering the machine at all, or water not draining after the cycle

In terms of repair costs, here's a realistic guide for the Addlestone area and across Surrey in 2026:

• Call-out and diagnosis: typically 50 to 80 pounds
• Heating element replacement: typically 100 to 180 pounds including parts and labour
• Circulation pump replacement: typically 120 to 220 pounds depending on the brand
• Control board replacement: typically 150 to 300 pounds - often not economical on machines over eight years old
• Water inlet valve: typically 70 to 130 pounds

As a rough rule, if the repair quote exceeds 50 to 60 per cent of the cost of a new equivalent machine, replacement usually makes more financial sense. A basic built-in dishwasher from Beko or Hotpoint now costs around 300 to 400 pounds, while a mid-range Bosch runs 500 to 700 pounds. That context helps when you're weighing up a repair estimate.

Questions About This Process

Why are my dishes coming out cloudy even though the dishwasher seems to be running fine?

Cloudy or filmy dishes are commonly caused by one of three things: low rinse aid levels, insufficient dishwasher salt in a hard water area, or limescale build-up on the heating element causing the water to heat unevenly. Check your salt and rinse aid levels first and top them up if needed. If the cloudiness persists after two or three cycles, run a hot maintenance wash with a descaler to clear limescale from the internal components. In Surrey's water supply areas, this is a routine issue rather than a sign the machine is broken.

How often should I clean my dishwasher filter in Addlestone?

In a typical household in Addlestone, cleaning the filter once a month is a good baseline. If you're running the machine daily or washing particularly greasy pots and pans regularly, every two to three weeks is more appropriate. A blocked filter is the most common cause of poor cleaning performance we see, and it's usually because the filter hasn't been touched in six months or more. It takes less than five minutes to remove, rinse and replace, so it's worth building into your routine.

Is it worth repairing an older dishwasher or should I just replace it?

It depends on the age of the machine and the nature of the fault. For machines under six years old with a simple fault like a failed heating element or pump, repair is typically the better value option. For machines over eight years old facing a control board or motor replacement, the repair cost often approaches or exceeds what a new entry-level machine costs. Our engineers across Surrey generally recommend getting a written quote before committing, and using that figure to judge against the cost of a replacement model with a warranty.