How To Clean A Dishwasher And Get Rid Of Smells

A dishwasher cleans your plates, but it needs a little care itself. Food scraps, grease and limescale build up over time, which can leave bits on your dishes, cause smells and stop the machine draining. This guide covers how to clean a dishwasher step by step, from the filter and spray arms to the door seals, plus how to keep smells and limescale away.

Before You Start

Switch the dishwasher off at the mains before you do any work on it, and make sure it has cooled down if it has just finished a cycle. Empty the racks, then pull out the bottom basket so you can reach the base of the tub. Keep your manual handy, as the way parts come out varies between models.

Stick to simple user maintenance. Never take panels off or try to get at wiring, pumps or hoses behind the machine yourself.

How To Clean A Dishwasher Filter

The filter sits in the base of the tub and catches food before it reaches the drain. Which? suggests cleaning it once or twice a month, or even weekly if you want the best results.

1. Lift out any large bits of food or broken glass you can see around the filter, wearing rubber gloves.
2. Remove the filter. On most machines it twists and pulls out.
3. Rinse the outer metal filter under hot water.
4. Clean the inner filter under the tap with a soft brush, such as an old toothbrush, to reach the mesh.
5. Refit it firmly, following your manual, so it locks back into place.

A dirty filter is behind many common problems. Which? lists four signs it needs attention: food left on dishes, an unpleasant smell when you open the door, a pool of water in the bottom, and visible debris on the filter itself.

Spray Arms And Door Seals

Clearing The Spray Arms

The spray arms spin and push water over your dishes. If their holes block, parts of the load will not get clean, and arms that do not turn properly can even cause leaks from the front. Which? suggests checking them every three months.

Remove the arms as your manual describes, poke the holes clear with a cocktail stick or toothpick, then rinse them under the tap. Refit them and spin them by hand to check they turn freely before you close the door. When you reload, make sure tall items and large pans do not block the arms.

Wiping The Door Seals And Rim

Food that collects on the door rim can make the rubber seals perish, and a damaged seal may start to leak. Which? recommends a quick weekly wipe of the rim and seals with a damp cloth, plus a more thorough clean once a month.

Pay attention to the bottom edge of the door, where drips and crumbs gather. If a seal looks split or has come away, it may need replacing. Which? notes the upper seal can often be swapped easily, but the lower one usually needs professional help.

Standing Water And Smells

If Water Is Left In The Bottom

If water is left in the bottom after a wash, the most common cause is a blocked filter, so clean that first. After that, check the waste hose behind or under the machine is not kinked, and that the sink waste pipe it connects to is not blocked. If you have an integrated dishwasher, Which? advises getting an engineer to deal with a blocked waste hose.

Getting Rid Of Smells

Most dishwasher smells come from old food trapped in the filter, so a thorough filter clean is the first fix. After that, wipe the seals, run a hot maintenance wash and keep the machine in regular use.

Leaving the door slightly ajar after a cycle from time to time lets air circulate, which Which? says helps stop mildew, mould and bacteria building up. Scrape plates into the bin before loading, too. You do not need to rinse them under the tap first. Our guide on how to get the most out of your dishwasher explains how to load it well, and the dishwasher programmes guide covers which settings to use.

A Hot Maintenance Wash With Dishwasher Cleaner

A hot wash with the machine empty helps clear grease and guards against smells. Which? suggests a hot empty wash with a proper dishwasher cleaner every six months, following the instructions on the pack.

Which? advises against home alternatives such as lemon juice or white vinegar, and says you should never use bleach in a dishwasher. If your machine has a self-clean or maintenance programme, use that for the cleaning wash.

The Which? guide to cleaning a dishwasher sets out how often to do each job.

Limescale, Salt And Rinse Aid

In hard water areas, limescale can build up inside the machine and leave glasses cloudy. Dishwasher salt softens the water, which stops limescale forming and helps your detergent work properly. Rinse aid helps dishes dry without streaks.

• Top up salt and rinse aid when the warning lights come on. If your machine has no lights, Which? suggests refilling salt about once a month.
• Use proper dishwasher salt, never table salt, which contains additives that do not suit the softening unit.
• Keep adding salt even with all-in-one tablets, as the salt in them is often not enough on its own.
• Set the water hardness on your machine to match your area. Your water supplier can tell you the hardness level, and your manual will explain the setting.

When To Call An Engineer

If the machine still will not drain after you have cleaned the filter and checked the hose, leaks from the bottom of the door, will not start or makes grinding noises that cleaning the spray arms has not cured, switch it off at the mains and get it looked at. Pumps, motors and control boards are jobs for a qualified engineer. Appliance Repair Men handle dishwasher repairs in Ormskirk and across Merseyside and West Lancashire.

Quick Checklist

• Every week: wipe the door rim and seals.
• Once or twice a month: clean the filter.
• Every three months: clear and rinse the spray arms.
• Every six months: hot empty wash with dishwasher cleaner.
• As needed: top up dishwasher salt and rinse aid.
• Always: switch off at the mains before cleaning.

You will find more practical home guides at Beyond The Garden Gates.

Kaan Rassad

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