Dishwasher Not Cleaning Properly - What to Check in Arundel

Published September 2026 | Dishwasher Not Cleaning Properly

How Long Should a Dishwasher Last and What Affects That

Dishwashers commonly last between 10 and 15 years when they're looked after properly. Some machines from reliable brands like Bosch or Miele push past that comfortably - our engineers have serviced Bosch dishwashers in West Sussex that are still running well at 17 or 18 years. Budget models from brands like Beko or Hotpoint tend to sit closer to the 8 to 10 year mark, and that's not a criticism - they're priced accordingly.

What cuts that lifespan short is almost always neglect rather than inherent weakness in the machine. The three biggest factors our engineers see repeatedly are water hardness, filter maintenance, and loading habits.

Water hardness is a serious issue in this part of England. West Sussex sits on limestone geology, and the water coming out of your tap in Arundel carries a significant mineral load. That limescale deposits on heating elements, spray arms, and internal seals with every single cycle. Left unchecked, it's the single biggest cause of premature dishwasher failure we deal with in this area.

The filter at the base of the machine catches food debris from every cycle. If you're not cleaning it regularly, that debris decomposes, restricts water flow, and forces the pump to work harder than it should. A pump that's been straining against a blocked filter for two years doesn't last as long as one that's been properly looked after.

Loading habits matter more than people expect. Overloading, blocking spray arm rotation, and using the wrong programmes all contribute to poor wash results and, over time, to mechanical strain. The brand matters too. Our engineers consistently find that Bosch, Siemens, and Miele machines last longer and develop fewer fault patterns than some of the budget alternatives. LG and Samsung sit in the middle ground - solid machines but with specific fault patterns we see regularly on callouts across West Sussex.

The Maintenance That Actually Makes a Difference

Most dishwasher problems that lead to poor cleaning results are entirely preventable. Here's what actually moves the needle, based on what our engineers find on the majority of callouts where the machine is less than 10 years old.

Clean the filter regularly. This is the single most important maintenance task and the one most people skip. The filter assembly sits at the bottom of the dishwasher tub - on most machines it's a cylindrical mesh filter that twists out, plus a flat filter underneath it. Rinse this under the tap every two to four weeks. If you're running the machine daily, do it fortnightly. Food debris left in that filter doesn't just smell - it recirculates onto your dishes and causes the exact problem you're trying to fix.

Descale the machine on a schedule. In an area like Arundel, where water hardness is high, running a dishwasher cleaner or descaler through a hot cycle every one to three months is essential. Products like Finish Dishwasher Cleaner or Durgol work well. Don't substitute white vinegar for a proper descaler - it's mildly acidic and can damage rubber seals and pump components over time.

Check and clear the spray arms. The spray arms - the rotating components at the bottom and sometimes mid-level of the drum - deliver water under pressure to clean the dishes. Their holes block with mineral deposits and food particles. Remove the spray arms (they usually unclip or unscrew depending on the model) and use a cocktail stick or thin wire to clear each hole, then rinse thoroughly. If water can't spray out evenly, dishes won't get clean regardless of what detergent you're using.

Use the right detergent. Cheap detergent tablets deliver inconsistent results. The major brands - Finish Quantum, Fairy Platinum - are more expensive for a reason. If you're getting poor results and switching to a premium detergent fixes it, that's a cheap solution. Also check that your detergent dispenser is actually opening during the cycle. It's a common fault that goes unnoticed - the dispenser door jams and the tablet never dissolves.

Keep the salt topped up. Most modern dishwashers have an internal water softener that uses dishwasher salt to counteract limescale. If your machine has a salt compartment - check your manual, as most Bosch, Siemens, and Hotpoint machines do - keep it topped up at all times. Running without salt in a hard water area accelerates limescale damage significantly and shortens the machine's working life.

Warning Signs It Is Reaching End of Life

There's a clear difference between a dishwasher that needs maintenance and one that's on its way out. Here's what our engineers look for when assessing whether a machine is worth repairing.

Poor cleaning that persists after full maintenance. If you've cleaned the filter, descaled the machine, cleared the spray arms, and confirmed your detergent is working - and the results are still poor - you're likely looking at a pump fault, a failing water inlet valve, or a deteriorating heating element. These are mechanical problems that need a qualified engineer.

Dishes coming out cold or greasy. If dishes are dirty and the interior feels cool at the end of a cycle, the heating element or thermostat is probably failing. The heating element raises water to the temperature needed to dissolve grease and activate detergent enzymes. Without it, even a brand new detergent tablet won't save the wash.

Unusual noises during operation. Grinding, rattling, or a persistent humming that wasn't there before usually indicates a failing wash pump or drain pump. These are not cheap repairs. Pump replacements commonly run to 100 to 200 pounds including parts and labour, which raises the repair-or-replace question depending on the machine's age.

Water pooling under the machine. A small amount of condensation around the door seal is normal. Water pooling on the floor is not. Door seals are usually a reasonable repair, but internal leaks from the sump or pump housing often indicate the machine is approaching the end of its economic life.

Error codes on the display. Modern dishwashers display fault codes when sensors detect problems. Our engineers use the Voltrade GoFIX diagnostic tool to read these codes accurately across brands including Bosch, Samsung, LG, and Hotpoint. A code that looks alarming is sometimes a minor sensor fault, while a code that looks minor can indicate a deeper control board issue. Don't try to diagnose these by Googling the code alone - the same code means different things on different models.

Repair vs Replace - The Honest Calculation

The repair versus replace decision comes down to a simple calculation. If the repair costs more than half the price of a comparable new machine, replacement is usually the better call. For a budget Beko or Hotpoint, that threshold is low - a new machine might cost 300 to 400 pounds. For a high-end Bosch Serie 6 or 8, where replacement costs 600 to 900 pounds, a 200 pound repair is clearly worthwhile.

Age matters enormously here. A repair on a 3-year-old machine is a good investment. The same repair on a 12-year-old machine, where the next fault is likely within 18 months, often isn't. Common repair costs our Arundel customers typically encounter are as follows:

• Filter and spray arm service call: 60 to 100 pounds (avoidable with regular maintenance)
• Door seal replacement: 80 to 150 pounds
• Water inlet valve: 100 to 180 pounds
• Wash pump replacement: 120 to 220 pounds
• Heating element: 100 to 170 pounds
• Control board: 150 to 300 pounds or more - rarely worth doing on machines over 8 years old

Parts availability also drops significantly after 7 to 10 years for most brands. Samsung and LG parts can become very difficult to source once a model is discontinued. Bosch and Siemens tend to maintain better parts availability for longer, which is part of why their machines often work out cheaper to own over the long term, even though they cost more upfront.

Annual Service - What It Should Include

An annual dishwasher service from a qualified appliance engineer should cover considerably more than just cleaning the filter. Here's what a proper service visit should include, so you know what to expect and what to ask for.

A thorough clean of the filter assembly, spray arms, door seal, and interior is the starting point. The engineer should also check the door hinges and springs - a door that doesn't close properly under spring tension wastes water, causes poor wash results, and can allow steam to escape and damage surrounding cabinetry. The detergent dispenser mechanism should be tested and the door seal checked for cracks, mould, or compression failure.

On the mechanical side, the pump inlet should be checked for debris, the water softener inspected and salt topped up if needed, and the machine run through a diagnostic cycle to check temperature performance, water inlet pressure, and cycle completion time. Our engineers run the Voltrade GoFIX diagnostic tool on every service visit - it picks up fault codes and sensor drift that wouldn't be obvious from a visual check alone, and often catches problems before they develop into a breakdown.

The engineer should also verify that water connections are secure and that the drain hose is routed correctly. A kinked drain hose or a drain hose positioned without the proper high loop can cause drainage problems that produce exactly the same symptoms as a failing pump - dishes sitting in dirty water, residue left behind on glassware and cutlery.

An annual service typically costs between 60 and 100 pounds in the West Sussex area, depending on the engineer and whether any minor parts are needed. On machines under 10 years old, it's a worthwhile investment that extends life and catches issues early.

Simple Habits That Extend the Life by Years

You don't need to be technical to add several years to your dishwasher's life. These habits cost almost nothing and make a real difference over time.

Scrape, don't rinse. You don't need to rinse dishes before loading them - modern detergent is formulated to work with food residue present. But do scrape off large food pieces to protect the filter. Putting dishes in coated with leftover food blocks the filter fast and forces you to clean it more often.

Don't overload. It's tempting to squeeze in one more bowl, but overloading blocks spray arm rotation and prevents water from reaching all surfaces. The result is dirty dishes that need running through again - doubling the wear on the machine for no gain.

Use rinse aid consistently. In hard water areas like the Arundel area, rinse aid isn't optional - it's essential. It prevents limescale spotting on glassware, helps dishes dry properly, and reduces the mineral load on the interior of the machine. Set the dispenser to a mid-to-high level to account for local water hardness.

Run hot cycles regularly. If you mainly use eco or quick cycles, run a full 65 or 70 degree cycle every couple of weeks. The higher temperature dissolves grease and prevents build-up in the pump and drain system that a lower-temperature cycle won't shift.

Leave the door ajar after a cycle finishes. Open the door slightly once the programme ends to let steam escape. Trapping moisture inside encourages mould on the door seal and accelerates seal deterioration, especially in warmer kitchens.

Check that the machine is level. A dishwasher that's not sitting level doesn't drain completely at the end of a cycle. Over time, standing water causes pump wear and seal deterioration. Use a spirit level and adjust the feet if needed - it takes five minutes and can prevent years of gradual damage.

Maintenance Questions

How often should I clean my dishwasher filter?

For a household running the dishwasher daily, the filter should be removed and rinsed under the tap every two weeks. If you use the machine less frequently, once a month is typically sufficient. A blocked filter is the most common cause of poor wash results that our engineers encounter on callouts across Arundel and the surrounding West Sussex area - and it's entirely preventable with a few minutes of routine maintenance.

Why are my dishes still dirty after a full cycle?

The most common causes are a blocked filter, clogged spray arm holes, low or empty rinse aid, or a detergent dispenser that isn't opening properly during the cycle. In hard water areas, limescale on the heating element also reduces the wash temperature, leaving dishes greasy and poorly cleaned. Work through these checks in order before calling an engineer - in most cases one of them is the issue and can be fixed without a callout.

How much does it cost to repair a dishwasher that is not cleaning properly in Arundel?

For maintenance issues such as blocked filters, spray arm cleaning, or a descale service, a visit typically costs between 60 and 100 pounds. For mechanical faults like pump or heating element replacement, expect to pay between 100 and 220 pounds depending on the part and the machine's age. If the repair cost exceeds roughly half the price of a comparable new machine, replacement is usually the better financial decision in the long run.

Is it worth repairing a dishwasher that is more than 10 years old?

It depends on the fault and the brand. Minor repairs - door seals, inlet valves, thermostat faults - are often worth doing on a well-maintained machine regardless of age. Major repairs like pump or control board replacement rarely make sense on a machine past the 10 year mark, because further faults are likely within the next couple of years. Our engineers will always give you a clear assessment of the options before quoting for any repair work.