If your dishwasher doesn’t drain, it can be caused by a wider issue for a drain specialist, or it may also be an issue with the appliance. Here is a quick checklist you can go through to decide whether an issue with your dishwasher is related to the machine or something deeper in the drainage system that may require an appliance service provider or drain specialist such as ourselves. Whenever working with an appliance, it’s good safety practice to disconnect it from the mains first.
Dishwasher Won’t Drain: Checking the Dishwasher Filters
We often get called out to customers’ homes where they can see that the machine won’t empty water. The most common cause is that the water is never leaving the machine due to blocked filters. As most dishwasher discharge hoses are fitted loosely into the drainage waste pipe, a blocked drain will most likely overflow onto the floor here rather than backing up into the machine. So it’s best to check the machine for blockages before you consider a drain blockage.
Before you begin checking over your machine, it’s a good idea to power it off. Next, open the dishwasher and check the filter located inside at the bottom of the unit. Removing this, you may find debris and large food particles. Remove the food particles and make sure the filter is thoroughly cleaned. You can then try to replace the filter and restart the dishwasher. If the dishwasher won’t drain after this but the drain waste pipe is not backed up, there may be a blockage or failure within the inner workings of the machine in which case you should contact an appliance service specialist. If you feel the drainage waste pipe is backed up, you can try the next step below.
Is water draining slowly in nearby sinks?
Do you know where the wastewater outlet is for your dishwasher? Very often, these will connect into a nearby sink or drain. If a nearby sink is draining slowly, this would indicate a potential local blockage – especially if you don’t have the same issue in other parts of your household or building. You could try to unblock the sink with a homemade drain unblocking solution to clear away those drains (we do not recommend chemical drain unblockers as they damage the pipes). A plunger may also help if you have one to hand (but make sure to use the plunger first as if you pour harsh chemicals into your drain they risk splashing onto your skin or eyes). If this doesn’t clear the blockage, you can attempt to take things further yourself. Or you can consider calling a drain service provider such as Dyno-Rod.
If there are no blockages in the nearby sink, or you don’t see an improvement with the dishwasher when you switch it back on, the next step is to quickly check for any kinks or visible pinching of the drainpipe behind the dishwasher. Be careful when sliding the dishwasher out; The wastewater hose may be short, and too much force can damage the pipe or connection. So take your time and make sure not to pull the machine out too far. If you cannot do this check or you are certain the waste pipe from the machine is clear, you may need to consider getting an appliance service professional to take a look.