Quick answer
A noisy dishwasher during draining may have a clogged drain pump or filter. Turn off power and water, check for blockages, and clean or replace affected parts if needed.
Confirm the symptom
- Loud noise during the drain cycle
- Noise is rhythmic or grinding
- Happens only when draining, not during wash
Tools and prep
- Screwdriver set
- Plumber's putty or sealant
- Bucket or towel
- Flashlight
- Rubber gloves
- Owner’s manual
Step-by-step troubleshooting
- Turn Off Power and WaterDo: Shut off the circuit breaker for the dishwasher and close the water supply valve.Observe: Dishwasher is powered down and water supply is off.Means: Prevents electrical hazards and water leaks during inspection.Next: 2
- Check the Drain HoseDo: Locate the drain hose under the sink or behind the dishwasher and inspect for kinks or clogs.Observe: Hose is clear or shows blockage.Means: Kinks or clogs can restrict water flow and cause noise.Next: 3
- Clean the Drain FilterDo: Remove the drain filter at the bottom of the dishwasher and clean it with warm, soapy water.Observe: Filter is free of food particles and debris.Means: A clogged filter can cause the pump to work harder, creating noise.Next: 4
- Inspect the Drain PumpDo: Access the drain pump (refer to the manual) and check for obstructions or damage.Observe: Pump is clear or shows signs of wear.Means: A clogged or faulty pump is a common source of noise.Next: 5
- Test the DishwasherDo: Reconnect power and water, then run a short cycle to see if the noise persists.Observe: Noise is resolved or still present.Means: Determines if the issue was due to a clog or requires further action.Next: 6
- Replace Damaged PartsDo: If the pump is damaged or the noise continues, replace the drain pump or consult a professional.Observe: Dishwasher runs quietly after replacement.Means: Damaged parts may need professional replacement for safety and efficiency.Next: 7
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Clogged Drain Filter Food particles and debris block water flow, causing the pump to strain. | Common | Easy | Drain Filter |
| Clogged Drain Hose Mineral buildup or debris in the hose restricts drainage and causes noise. | Common | Easy–Medium | Drain Hose |
| Faulty Drain Pump Worn bearings or motor in the pump create grinding or loud noises during drainage. | Sometimes | Medium | Drain Pump |
| Loose or Worn Pump Impeller The impeller may become loose or damaged, causing vibration and noise. | Sometimes | Medium | Drain Pump Assembly |
| Air Gap Blockage An air gap prevents backflow but can become clogged, causing gurgling or bubbling sounds. | Rare | Easy | Air Gap |
| Improper Installation A poorly installed drain hose or pump can lead to noise during operation. | Rare | Medium | Drain Hose or Pump |
| Worn Motor Bearings Over time, motor bearings can wear out, leading to loud noises during the drain cycle. | Rare | Hard | Drain Pump Motor |
Parts matching
Common parts needed to fix a noisy dishwasher during draining include:
- Drain Filter
- Drain Hose
- Drain Pump
- Air Gap
- Drain Pump Assembly
- Drain Pump Motor
Always refer to your dishwasher’s manual to confirm part compatibility before purchasing replacements.
When to call a professional
- Noise persists after cleaning filters and hoses
- Drain pump is visibly damaged or leaking
- You hear electrical sparking or burning smells
- You are unsure about electrical or plumbing connections
- The dishwasher does not drain at all after troubleshooting
FAQ
Can a clogged air gap cause a noisy dishwasher?
Yes, a clogged air gap can cause gurgling or bubbling sounds during drainage. Clean the air gap with a brush and warm water to resolve the issue.
How often should I clean the drain filter?
Clean the drain filter every 1–2 months to prevent clogs and maintain efficient drainage.
Is it safe to replace the drain pump myself?
If you are comfortable with basic plumbing and electrical work, replacing the drain pump is possible. Otherwise, consult a professional to avoid damage or injury.
Why does my dishwasher make noise only when draining?
Noise during drainage often indicates a clog in the filter, hose, or pump. Check these components for blockages or damage.
Can hard water cause drainage noise?
Yes, hard water can lead to mineral buildup in the drain hose or pump, causing noise. Use a water softener or vinegar to clean affected parts.