Why Your Dishwasher Needs Cleaning Too

A dishwasher is one of the hardest-working appliances in the kitchen, and yet it is often the last thing we think to clean. That is a little unfair, because every cycle it runs leaves behind a thin film of food debris, grease and limescale inside the machine. Over time those deposits build up in the filter, the door seal and the spray arms, and the result is exactly what you would expect: cloudy glasses, gritty plates, a lingering smell and a machine that seems to be working harder for noticeably worse results.

The good news is that a proper clean takes about half an hour, needs nothing more exotic than bicarbonate of soda, and will genuinely improve how your dishes come out. Here is how to do it properly.

Start With the Filter

If you only do one thing, do this. The filter sits at the bottom of the tub, usually as two or three interlocking parts. Twist the top section anticlockwise to release it and lift everything out.

• Rinse the parts under a warm tap to shift the loose debris first.
• Scrub the mesh with an old toothbrush and a little washing-up liquid, working around the rim where grease collects.
• Check the recess the filter sits in, too — a quick wipe with a damp cloth removes the sludge that gathers underneath.
• Never put the filter in the dishwasher itself; the heat can warp the plastic.

Aim to rinse the filter weekly and give it a proper scrub once a month. If you live in a hard-water area or cook a lot of rich, greasy food, do it a little more often than that.

Scrub the Door Seal and the Hidden Edges

The rubber gasket around the door is where odours like to hide. Food particles and moisture collect in its folds, and if you leave them, you will often find black spots of mould appearing there.

• Wipe all the way around the seal with a cloth dipped in warm soapy water, pulling the rubber gently apart so you can reach inside the fold.
• Use a cotton bud or a small brush for the awkward corners.
• Wipe the door edges, the hinge area and the detergent dispenser recess while you are at it.
• For stubborn spots, make a paste from bicarbonate of soda and a little water, dab it on, leave for ten minutes, then wipe away.

Dry the seal properly afterwards rather than leaving it damp, and leave the door slightly ajar between washes so air can circulate.

Run a Hot Cycle With Bicarbonate of Soda

With the machine empty, sprinkle around 200g of bicarbonate of soda across the base of the tub. This is the workhorse step: it neutralises odours, lifts grease and gently deodorises the whole interior without harsh chemicals.

Now select the hottest and longest cycle your machine offers and let it run all the way through. If you have hard water, add a tablespoon of citric acid to the base alongside the bicarbonate — it is brilliant at dissolving limescale.

For a freshening rinse, you can also place a heatproof bowl holding about 250ml of white vinegar on the top rack. Keep the vinegar separate from the bicarbonate rather than mixing them in the same place, as they simply cancel each other out. When the cycle finishes, wipe round the inside with a clean cloth and leave the door open to dry.

Check the Spray Arms

It is easy to forget, but blocked spray arms are a common reason for poor washing results. Unclip them if your model allows, then hold them up to the light and look through the holes. Poke out any debris with a cocktail stick or a piece of thin wire, and rinse them under the tap before refitting. If the arms are removable, a soak in warm soapy water will loosen anything stubborn.

Keep It Fresh Between Deep Cleans

Once you have done the hard work, a few small habits will keep your machine performing well for months.

• Run a hot cycle occasionally even when the machine is only half full, as this helps flush through grease.
• Top up the salt reservoir with proper dishwasher salt, not table salt, and keep rinse aid topped up for better drying and less spotting.
• Scrape plates rather than rinsing them heavily; too much food going down the drain can clog the filter.
• Load sensibly — don't block the spray arms or nest bowls tightly together.

Repeat the full routine every month and you should notice the difference within a couple of cycles: clearer glasses, cleaner plates and no lingering smell when you open the door. It is a small job that quietly pays for itself, and your dishwasher will thank you for it.