Happy Drains Blog

How to Keep Your Dishwasher from Clogging

Like sinks, dishwashers face the danger of blockage. Fortunately, there are some simple preventative measures you can take to keep your dishwasher from clogging.


No food allowed

Dishwasher etiquette is the same as your sink; there shouldn’t be any food debris, including oil or grease, going in the dishwasher. As your dishwasher is connected to your sink pipe, any food or oil could lead to a blockage in your dishwasher or sink. It’s best to get into the habit of scraping your food waste into the bin before you place it in your machine. This also means the water used in the dishwasher will stay cleaner because it won’t spray food deposits around your dishes.

Drain cleaner

You can periodically clean away hard water from your dishwasher with non-corrosive dishwasher drain cleaner. Hard water can cause mineral deposits to build up in the pipes and your appliance; this can cause the dishwasher to work less effectively or lead to clogging. Another option is to use a quart of distilled white vinegar in the machines each month. You can do so by throwing some into the bottom of the dishwasher, then running the machine empty.

Hot water cycle

Using the hot water cycle can help remove any build up in the machine which cooler/shorter washes can’t do. Cool/short washes make it easier for the build up to continue because it doesn’t have the heat to break down any deposits. Running a few hot cycles or full cycles a week could keep your machine from blockages.


At times, clogging does take place and there are simple ways you can repair this.

Clean the filter

You can extract the food, oil or fat build up that’s clogging your machine by cleaning out the filter. This can be done with some soap and hot water – there are plenty of online guides that can help. Make sure any gunk you do remove from the filter goes into the bin so it doesn’t end up down the sink’s drain, which would defeat the point of this exercise.

Check the pipes

You can inspect the pipes behind the dishwasher that are connected to your sink. It’s possible that as water has left the dishwasher and cooled down, any grease or fat in the water has solidified and clogged the drain. It’s worth inspecting the pipes if you have fears that any waste left on your dirty dishes have sabotaged your pipes.


The dishwasher pump consists of two impellers. The upper one is for pumping water in the machine and the lower is for pumping it out into the drain. Make sure to clean out any gunk that might be residing in the upper and lower impellers, which could be preventing water from moving efficiently through your machine.

Keeping your dishwasher from clogging can be easily prevented, but sometimes it can’t be helped. In these instances, it’s good to get expert advice and help which you can receive from us. Feel free to call us on the numbers below or contact us online with any enquiries.