Appliances
Dishwasher Not Draining: Troubleshooting Guide
Work through the common causes of standing water in a dishwasher before replacing parts.
Common symptoms
- Water remains after the cycle
- The dishwasher hums but does not drain
- Water backs up into the sink
- A drain error appears
Likely causes
Start with the simplest observable cause and avoid replacing parts until the failure has been identified.
- A clogged filter
- Blocked drain hose
- A clogged sink connection or air gap
- A jammed pump
- A disposal inlet plug left in place after installation
Tools and materials
- Sponge
- Bucket
- Screwdriver
- Flashlight
- Gloves
Step-by-step procedure
- Cancel the cycle and use the model’s drain function once.
- Disconnect power and remove standing water with a sponge or wet vacuum.
- Remove and clean the filter according to the manufacturer’s instructions.
- Inspect the sump area for food, labels or glass without forcing pump components.
- Check the sink drain, disposal connection and air gap. Confirm a new disposal’s dishwasher inlet plug was removed.
- Inspect the drain hose for kinks and verify its required high loop or air-gap arrangement.
- Restore power and run a short test cycle while checking all hose connections for leaks.
Common mistakes to avoid
- Reaching into cloudy water without gloves
- Running repeated cycles while water remains
- Removing pump covers without model-specific instructions
- Leaving the drain hose flat beneath the sink
Verify the repair
Test the repaired component through several normal operating cycles. Watch, listen and feel for leaks, heat, movement, unusual noise or odour. Stop immediately if the condition worsens. Document the work and retain part numbers, receipts and manufacturer instructions for future maintenance.
When to call a professional
Call an appliance technician if the pump is noisy, electrically unresponsive, leaking or inaccessible, or if error codes persist.
Editorial note
This guide is written for general homeowner education. Building codes, product instructions, warranties, condominium rules and licensing requirements vary. The safest compliant method for your property always takes precedence.