Dishwasher Not Draining in the UK: Fix It Yourself

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Quick answer

If your dishwasher isn't draining, first check for a clogged filter or drain hose. Clear any blockages and ensure the drain pump is working. If the problem persists, the pump or float switch might need replacing.

Confirm the symptom

Tools and prep

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Prep & safety

Step-by-step troubleshooting

Check the Filter

Do: Remove the bottom rack and locate the filter. Twist or unscrew it to remove.

Observe: Look for food particles or debris blocking the filter.

Means: A clogged filter can prevent proper drainage.

Next: Clean the filter with a brush and water, then reassemble.

Inspect the Drain Hose

Do: Locate the drain hose at the back of the dishwasher. Check for kinks or clogs.

Observe: Look for blockages or bends in the hose.

Means: A blocked or kinked hose can stop water from draining.

Next: Clear any blockages and straighten the hose if necessary.

Test the Drain Pump

Do: Listen for the drain pump during a cycle. You can also check for obstructions in the pump area.

Observe: The pump should run and push water out.

Means: A faulty pump may need to be replaced.

Next: If the pump is not working, proceed to check the float switch.

Check the Float Switch

Do: Locate the float switch near the bottom of the dishwasher. Try moving it manually.

Observe: The switch should move freely and not be stuck.

Means: A stuck float switch can prevent the dishwasher from draining.

Next: If the float switch is faulty, it may need to be replaced.

Examine the Air Gap

Do: Check the air gap on the countertop for blockages. Remove the cap and clean it.

Observe: Look for debris or blockages in the air gap.

Means: A clogged air gap can hinder drainage.

Next: Clean the air gap thoroughly and reassemble.

Verify the Drain Pipe Connection

Do: Ensure the drain pipe is securely connected to the household drain.

Observe: The connection should be tight and free of leaks.

Means: A loose connection can cause drainage issues.

Next: Tighten or reconnect the drain pipe if necessary.

Common causes table

CauseWhyLikelihoodDifficultyPart often needed
Clogged FilterFood particles and debris can block the filter, preventing water from draining.HighLowFilter
Blocked Drain HoseA kink or clog in the drain hose can stop water from exiting the dishwasher.HighMediumDrain Hose
Faulty Drain PumpA malfunctioning drain pump cannot push water out of the dishwasher.MediumHighDrain Pump
Stuck Float SwitchA float switch that is stuck can prevent the dishwasher from draining properly.MediumMediumFloat Switch
Clogged Air GapAn air gap that is blocked can restrict water flow from the dishwasher.MediumLowAir Gap Cap
Loose Drain Pipe ConnectionA loose connection can cause leaks and drainage problems.LowLowDrain Pipe

Parts matching

When replacing parts, ensure they match your dishwasher model. Check the manufacturer's specifications for compatibility.

Consult your dishwasher's manual for specific part numbers and installation instructions.

Recommended products

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When to call a pro

FAQ

How often should I clean the dishwasher filter?

Clean the filter every 1-2 months to prevent clogs and maintain performance.

Can a clogged air gap cause drainage issues?

Yes, a clogged air gap can restrict water flow and lead to drainage problems.

What should I do if the drain pump is not working?

Check for obstructions first. If the pump is faulty, it may need to be replaced by a professional.

Is it normal for the dishwasher to make gurgling sounds during draining?

Occasionally, gurgling sounds can be normal, but persistent noises may indicate a blockage or pump issue.