How to Fix a Dishwasher Not Draining

Overview

A dishwasher that won't drain leaves water in the bottom. This guide covers diagnosing and fixing drain issues.

Step-by-Step Fix

1. First and foremost, ensure your safety by completely switching off the dishwasher at the mains power supply; this usually involves flipping the corresponding breaker at your consumer unit or unplugging it directly from the wall socket. Confirm the power is off by trying to turn the dishwasher on before proceeding with any further steps.
2. Carefully pull out the lower dish rack from the dishwasher tub to gain clear access to the bottom of the appliance. Locate the filter assembly, which typically involves twisting or unclipping a cylindrical or flat component in the centre or rear of the base.
3. Once the filter is removed, rinse it thoroughly under a running tap, using an old toothbrush or stiff brush to dislodge any food particles, grease, or debris trapped in its mesh. Ensure all parts of the filter, including any fine screens, are completely clear before reinstalling it securely.
4. Locate the drain hose at the rear of your dishwasher; it's usually a corrugated plastic hose that connects to your under-sink plumbing. Visually inspect the entire length of the hose for any obvious kinks, bends, or crushing that could be restricting water flow, and carefully straighten any you find.
5. Before testing, always ensure the power is off. Using a multimeter set to measure resistance (Ohms), disconnect the wires leading to the drain pump and touch the multimeter probes to the pump's terminals; a reading between 10-20 Ohms generally indicates a healthy pump, whereas an infinite reading suggests an open circuit and a faulty pump.
6. If your multimeter test confirmed the drain pump is faulty (e.g., an infinite resistance reading), you'll need to replace the component. Purchase a new pump specifically designed for your dishwasher model and carefully follow the manufacturer's instructions for installation, ensuring all connections are secure before restoring power and testing.

Common Symptoms & Diagnostic Resolutions

Review the common error codes and operating symptoms below to quickly identify the root cause of the fault before ordering replacement parts.

Frequently Asked Questions