How to Maintain Your Dishwasher (And What Happens When You Don’t)

Your dishwasher works hard. Day after day, it tackles greasy plates, baked-on food, and everything in between. But like any hardworking appliance, it needs a bit of care to keep performing at its best.

After 30 years of attending dishwasher repairs across Bath and the surrounding areas, we’ve seen it all. From machines that have lasted 15+ years with proper care, to relatively new models that have failed because of neglect. The difference? Usually just a few minutes of maintenance each month.

Let’s talk about how to keep your dishwasher running smoothly and what we typically find when homeowners skip the basics.

Why Dishwasher Maintenance Matters

Think of your dishwasher as a small washing machine for dishes. It uses water, detergent, heat, and mechanical action to clean. All of these processes create buildup over time: food particles, grease, limescale (especially here in Bath’s hard water area), and detergent residue.

Without regular maintenance, this buildup leads to:

• Poor cleaning performance
• Unpleasant smells
• Blocked components
• Higher energy bills
• Expensive repairs
• Shortened appliance lifespan

The good news? Most dishwasher maintenance takes less than 10 minutes and can prevent hundreds of pounds in repair costs.

Essential Dishwasher Maintenance Tasks

Daily: Scrape Plates Before Loading

This isn’t really “maintenance,” but it’s the foundation of dishwasher care. You don’t need to pre-wash dishes, but do scrape off large food particles, bones, and excessive grease. Your dishwasher’s filter isn’t designed to handle whole chips or chicken bones.

Weekly: Clean the Filter

This is the single most important maintenance task, yet it’s the one most people skip.

How to clean your dishwasher filter:

1. Remove the bottom rack
2. Locate the filter assembly (usually at the base of the dishwasher)
3. Twist and lift out the filter (check your manual for the exact method)
4. Rinse under hot water, using a soft brush to remove stubborn debris
5. Check the filter cavity for any trapped items
6. Replace the filter, ensuring it’s properly locked in place

What we see when you don’t: Clogged filters are the number one cause of dishwasher problems. When filters get blocked, water can’t drain properly, leading to standing water at the bottom, poor cleaning results, and eventually pump failure. We’ve pulled out everything from broken glass and fruit stickers to small cutlery items lodged in filters.

Weekly: Wipe Down the Door Seal

The rubber seal around your dishwasher door traps food particles, grease, and moisture.

How to clean it:

• Use a damp cloth with a bit of washing-up liquid
• Wipe around the entire seal, getting into the folds
• Pay special attention to the bottom where debris accumulates
• Dry with a clean cloth

What we see when you don’t: Mouldy, smelly seals that eventually degrade and leak. Black mould buildup is common in neglected seals, and once it takes hold, it’s difficult to remove completely. In severe cases, the seal needs replacing.

Monthly: Clean the Spray Arms

Those spinning arms with holes spray water to clean your dishes. When holes get blocked, cleaning performance drops significantly.

How to clean spray arms:

1. Remove both upper and lower spray arms (they usually just lift or twist off)
2. Check each hole for blockages
3. Use a toothpick or skewer to clear blocked holes
4. Rinse under hot water
5. Reattach the arms, ensuring they spin freely

What we see when you don’t: Limescale and food particles block the spray holes, resulting in poorly cleaned dishes. We often find dishwashers where only half the spray holes are functioning. The machine works harder, uses more energy, and still leaves dishes dirty.

Monthly: Run a Cleaning Cycle

Even with regular filter cleaning, grease and limescale build up inside your dishwasher.

How to do it:

1. Remove all dishes
2. Place a dishwasher cleaner in the machine (or use a cup of white vinegar on the top rack)
3. Run the hottest, longest cycle
4. For stubborn limescale (common in Bath), use a dedicated descaler product

What we see when you don’t: Thick limescale deposits on heating elements, spray arms, and internal pipes. Grease buildup creates foul smells and provides a breeding ground for bacteria. The combination reduces efficiency and can cause components to fail prematurely.

Monthly: Check and Top Up Salt and Rinse Aid

If you have a water softener in your dishwasher (most modern ones do), it needs salt to function. Rinse aid helps water sheet off dishes, preventing spots and streaks.

How to maintain them:

• Check the salt reservoir indicator light (if your model has one)
• Top up salt when needed, using dishwasher salt specifically, not table salt
• Keep the rinse aid dispenser filled
• In hard water areas like Bath, you might need to adjust settings to use more of both

What we see when you don’t: In Bath’s very hard water area, running without salt is asking for trouble. Want to check your exact water hardness? Wessex Water provides a water hardness checker where you can enter your postcode. We see extensive limescale damage, cloudy glassware, and failed water softener units. The heating element takes the worst hit, often becoming so encrusted that it burns out.

Every 6 Months: Deep Clean

Give your dishwasher a thorough clean twice a year.

How to do it:

1. Remove all racks, cutlery baskets, and the filter
2. Inspect and clean the bottom sump area where water collects
3. Check the door hinges and clean any buildup
4. Wipe down the inside of the door and sides
5. Clean the detergent and rinse aid dispensers
6. Check the drain hose connection for kinks or blockages
7. Run an empty hot cycle with a strong descaler

What Happens When Maintenance Gets Ignored

Over the years, we’ve attended thousands of repair callouts. Here are the most common problems we see from lack of maintenance:

The Classic: “It’s Not Cleaning Properly”

What’s usually wrong: Clogged filter, blocked spray arms, or limescale buildup preventing proper water circulation.

The cost: Often preventable with basic maintenance. If caught early, a service visit can fix it. If left too long, you might need new spray arms, a new filter assembly, or even a new pump.

The Smelly Dishwasher

What’s usually wrong: Food debris rotting in the filter, grease buildup on seals, or stagnant water trapped somewhere in the system.

The cost: Usually fixable with thorough cleaning, but persistent smells can mean bacterial growth that’s hard to eliminate. In extreme cases, the smell permeates plastic components and won’t go away.

Standing Water at the Bottom

What’s usually wrong: Blocked filter, clogged drain hose, or failed drain pump. The pump often fails because it’s been working overtime trying to push water through blocked filters.

The cost: Filter cleaning might solve it if caught early. Otherwise, you’re looking at drain pump replacement (parts and labour).

Poor Drying Performance

What’s usually wrong: Empty rinse aid, failed heating element (often due to limescale), or blocked vents.

The cost: Rinse aid is cheap. A new heating element isn’t. In Bath’s hard water, we replace many heating elements that could have lasted years longer with proper descaling.

Complete Breakdown

What’s usually wrong: A combination of issues, usually starting with neglected maintenance and escalating to major component failure.

The cost: Sometimes it’s more economical to replace the dishwasher than repair it, especially if multiple components have failed.

The Real-World Impact: A Case Study

Last month, we visited two homes on the same street in Keynsham, both with the same Bosch dishwasher model purchased around the same time.

House 1: The homeowner cleaned the filter weekly, ran monthly descaling cycles, and kept salt and rinse aid topped up. Their dishwasher was running perfectly after seven years.

House 2: The filter had never been cleaned. It was so clogged that water couldn’t drain. The spray arms were blocked. Limescale had built up so severely on the heating element that it had failed. The cost to repair exceeded the value of replacing it.

Same dishwasher, same water supply, same timeframe. The only difference was maintenance.

Common Questions We Get Asked

“How do I know if my dishwasher needs descaling?”

In Bath’s hard water area, descale every month as a preventative measure. Signs you need it urgently include: cloudy glassware, white residue on dishes, longer cycle times, or visible limescale on internal components.

“Can I use vinegar instead of dishwasher cleaner?”

White vinegar works reasonably well for light cleaning and deodorising. For proper descaling, especially in hard water areas, use a product designed for the job. It’s stronger and more effective.

“My dishwasher is only a year old. Does it really need maintenance?”

Yes! Maintenance isn’t about age, it’s about use. A dishwasher used twice daily needs more care than one used twice weekly, regardless of age. Plus, early maintenance prevents problems from developing.

“Should I leave the door open between uses?”

Yes, leave it slightly ajar to allow moisture to escape. This prevents mould growth and keeps your dishwasher smelling fresh.

The Bottom Line

Ten minutes of maintenance each month can add years to your dishwasher’s life and hundreds of pounds to your pocket. It’s one of the best returns on investment for any household task.

But we also know that life gets busy, and sometimes maintenance slips. If your dishwasher is showing signs of neglect or isn’t performing as it should, don’t wait until it breaks down completely. Early intervention is always cheaper than emergency repairs.

As local engineers who’ve been fixing dishwashers in Bath for over 30 years, we can quickly diagnose problems, remove stubborn limescale buildup, and get your machine back to peak performance. We carry common parts on our vans, so most repairs are completed on the first visit.

Is your dishwasher not cleaning properly, smelling bad, or showing signs of limescale damage? Give us a call on 01225 429127 or 07733 110262. We serve Bath, Chippenham, Trowbridge, Keynsham, and all surrounding areas.