Dishwasher Not Hot Enough (Troubleshooting Guide)

On this page

Quick answer
Confirm the symptom
Tools and prep
Step-by-step troubleshooting
Common causes table
Parts matching
When to call a pro
FAQ
Related guides

Quick answer

Check the water temperature at the inlet, test the heating element with a multimeter, and ensure the thermostat is functioning. Replace faulty parts if needed.

Confirm the symptom

Dishes remain wet or not fully cleaned
Dishwasher runs but water doesn't feel hot
Dishes have food residue after cycles

Tools and prep

Multimeter
Screwdriver set
Thermal probe or thermometer
Safety gloves
Turn off power at the circuit breaker
Close the water supply valve

Step-by-step troubleshooting

Check Water Inlet Temperature
Do: Measure the temperature of the water entering the dishwasher using a thermometer.
Observe: Water temperature below 120°F (49°C)
Means: Insufficient hot water supply from the home's system
Next: Adjust water heater settings
Inspect Heating Element
Do: Visually check the heating element for signs of damage or mineral buildup.
Observe: Cracks, corrosion, or visible damage
Means: Faulty or worn-out heating element
Next: Test heating element with a multimeter
Test Heating Element with Multimeter
Do: Set the multimeter to ohms and test the heating element for continuity.
Observe: No continuity or resistance outside manufacturer specs
Means: Heating element is defective
Next: Replace the heating element
Test Thermostat
Do: Use the multimeter to check the thermostat for continuity.
Observe: No continuity or inconsistent readings
Means: Thermostat is faulty
Next: Replace the thermostat
Check High-Limit Thermostat
Do: Test the high-limit thermostat with a multimeter to ensure it's not tripped.
Means: High-limit thermostat is tripped or defective
Next: Replace the high-limit thermostat
Inspect for Clogs
Do: Clean the dishwasher's filter and check for clogs in the spray arms.
Observe: Debris or blockages in the filter or spray arms
Means: Poor water circulation affecting heat distribution
Next: Clean or replace the filter and spray arms
Verify Power Supply
Do: Ensure the dishwasher is receiving the correct voltage (usually 240V).
Observe: Voltage significantly below 240V
Means: Electrical supply issue
Next: Consult a licensed electrician

Common causes

Cause	Likelihood	Difficulty	Part often needed
Low Water Temperature The water heater isn't set high enough or is malfunctioning.	Common	Easy	None
Faulty Heating Element The heating element is damaged or worn out.	Common	Medium	Heating element
Defective Thermostat The thermostat fails to regulate the heating element.	Sometimes	Medium	Thermostat
Tripped High-Limit Thermostat Overheating or previous issues have triggered a safety shutdown.	Sometimes	Medium	High-limit thermostat
Clogged Filter or Spray Arms Debris restricts water flow and heat distribution.	Sometimes	Easy	Filter, spray arms
Electrical Supply Issues Incorrect voltage or tripped circuit breaker.	Rare	Hard	None
Control Board Failure The control board fails to activate the heating element.	Rare	Hard	Control board

Parts matching

If you need replacement parts, look for these components based on your dishwasher model:

Heating element (check voltage compatibility)
Thermostat (match part number from manual)
High-limit thermostat (specific to model)
Spray arms (ensure correct fit)
Filter (model-specific design)

Use your dishwasher's full model number when ordering parts for accuracy.

When to call a professional

If the heating element or thermostat tests fine but dishes still aren't hot
If you suspect electrical supply issues beyond basic checks
If you're uncomfortable working with electrical components
If the dishwasher is under warranty and you risk voiding it by DIY repairs

FAQ

How do I know if the heating element is bad?

Use a multimeter to test for continuity. No continuity means the element is defective.

Can a tripped high-limit thermostat be reset?

Some models allow resetting, but most require replacement if tripped.

Why is the water temperature low at the inlet?

The home's water heater may be set too low, or there could be a mixing valve issue.

Is it safe to run the dishwasher without a heating element?

It's not recommended, as dishes won't sanitize properly and may not dry well.

How often should I clean the dishwasher filter?

Clean the filter monthly to prevent clogs and maintain performance.