Why is My Dishwasher Not Draining?

Although it’s never a pleasant sight to open a dishwasher and realize the machine hasn’t drained properly, don’t overreact just yet. You might manage rectify the fault before you have to call a repair person or purchase a brand-new machine.

Standing water in your machine can be induced by a number of issues a number of which can be simple to rectify. Therefore, before you call a dishwasher repair service here is a list of possible issues you may troubleshoot by yourself. A number of which are not even a fault of the dishwasher itself.

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Ensure the dishwasher wasn’t stopped mid-program

It is possible that there is nothing stopping your dishwasher from emptying. Instead, the program may have been interrupted.

The program might have been cut short for any number of of reasons. Kids pressing controls, inadvertently leaning against the buttons, a power cut or opening the machine mid-program might all interrupt the program and mean your machine doesn’t drain.

If you believe this may be the situation, or you just want to be sure it’s not the issue start the machine again on a quick cycle.

A number appliances could have a drain function meaning it’s worthwhile checking your owners manual or consulting google to make sure.

Examine the waste disposal

If your dishwasher is attached to a garbage disposal inspect this before you move on as a blocked disposal will block the dishwasher from emptying. Turn on the disposal using fast running water to check there are no obstructions.

If you do find an obstruction drain un-blocker or a natural alternative may be sought after to remove the obstruction and so this could rectify the problem.

Check the plumbing for blockages

If you kitchen sink is draining slowly this might indicate an issue with the pipes rather than a problem with your machine.

In the case that the sink is draining inefficiently you may attempt putting some bicarbonate of soda and vinegar down the drain, leaving it for a while and then washing it through with boiling water.

A sink plunger could also be used to attempt to dislodge the obstruction.

This may be enough to allow the machine to empty so start a quick rinse and empty cycle now. If this hasn’t sorted the issue you can remove the dirty water by hand using a jug and a sponge and troubleshoot a few more likely causes.

Make sure you turn off the dishwasher to avoid electrocution.

If in the process of any of these investigations you suspect you have detected and fixed the fault there is no need to continue to the next issue. Just start an empty cycle to make sure your dishwasher is repaired.

Inspect and wash the filters

Corn Kernels, labels from tupperware, plastic lids and broken glass, plus food debris, can all obstruct the dishwasher filter. Clear film may also be difficult to see if you aren’t looking for it.

Take out the filter then give it a thorough wash before replacing it. Not all machines have their filter in the same place so you might need to refer to the instruction manual for this.

Is the waste hose obstructed?

The next place to check is the drain pipe. Stuck food, a kink in the hose or a crushed hose can all stop your dishwasher from emptying.

Depending on the position of the waste pipe (usually the corrugated one) you might have the means to view it by removing the kick board or you may need to move the machine away from the wall.

Visually examine the hose first to find out if there are any kinks or it’s been squashed. You could have the means to fix these issues by hand which will most likely deal with the issue, however, be aware that once this has occurred the probability of it happening again is massively increased so you might need to purchase a new hose.

If you are unable to find any obvious kinks or obstructions you can remove the waste water hose from the machine and blow through it to discover any blockages. Make sure you line the floor with newspaper or towels before you remove the hose as even if you have emptied the dishwasher there could still be waste water in the hose.

If you can’t blow through the waste hose this may be the problem.

Disconnect the other end of the hose and then give it a thorough clean to clear the blockage. If you can’t get rid of the blockage or the waste hose is cracked or degraded buy a new one. If you can clear the blockage then put the hose back and start a short program to make sure you have solved the problem.

You can also inspect where the hose connects under your sink as well. This is a common point for blockages to occur so if you do remove the waste pipe give this point a good clean as well.

Inspect the drain valve

You may manually inspect the drain valve to check it hasn’t got stuck. The drain valve will generally be located in the bottom of the machine on the valve bracket. Check your owners manual if you’re not sure.

Depressing the valve or giving it a wiggle should be enough to let you know if it’s stuck. If you are able to see an object blocking it carefully extract this. If you can’t, this may be the right time to ring a repair person unless you are confident in procuring and replacing the part on your own.

Check your pump is not blocked

Your appliance pump uses impellers that may become obstructed by pieces of glass or other objects. Check your pump isn’t blocked by taking off the cover and ensuring that the impellers can be easily rotated.

Listen to your dishwasher while it’s on

If it is making funny noises your pump or motor may be broken and need replacing.

Call a plumber

If none of the above investigations has repaired the issue, or you have reason to believe the pump, pump valve or motor are damaged, it may be a good time to get the professionals.

At least having tried to troubleshoot you have avoided having to pay a big repair fee for a blocked drain.