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AEG Dishwasher Not Heating
AEG Dishwasher Not Heating
Cold Washes – Common Causes
Is Your AEG Dishwasher Not Heating?
When your AEG dishwasher isn’t heating water, every wash cycle runs cold. Dishes come out with grease still on them, glasses stay cloudy, and detergent doesn’t dissolve properly. The cycle completes normally but cleaning performance is poor because water never reaches the correct temperature.
Most AEG dishwashers don’t display an error code when the heating fails – they simply run through the cycle without heating. You’ll notice the problem when dishes come out dirty despite using the correct program and detergent.
Quick check: Run a quick wash cycle and carefully open the door at the end. The dishes and interior should be hot to the touch. If everything is cold or lukewarm, the heating element has likely failed or there’s a fault preventing it from working.
What Causes AEG Dishwashers Not to Heat?
1. Failed Heating Element (Most Common)
The heating element is submerged in water and heats it during the wash cycle. Over time – typically 7-10 years – elements fail, either burning out electrically or developing a break in the heating coil.
In hard water areas like Bath and Wiltshire, limescale accelerates element failure. Heavy limescale coating insulates the element, preventing efficient heat transfer and eventually causing the element to overheat internally and fail.
2. Low Salt Levels Causing Heater Failure
AEG dishwashers use salt to regenerate the water softener, which protects the heating element from limescale damage. When salt levels run low, particularly in hard water areas, limescale builds up rapidly on the element causing premature failure. Many heating faults we see are directly linked to poor salt maintenance.
3. Faulty Temperature or Turbidity Sensor
The NTC temperature sensor monitors water temperature and tells the control board when to switch the heating element on and off. The turbidity sensor measures water cleanliness. On some AEG dishwashers, both sensors are built into a single combined unit located at the base of the machine. If either sensor fails or becomes dirty, it can affect the dishwasher’s heating behaviour – the control board may not activate the element, or the machine may run shorter cycles or skip heating phases.
4. Control Board Fault (Rare)
The main control board sends power to the heating element. If the board develops a fault or there’s damaged wiring, heating won’t work even though the element itself is fine. This is less common but needs checking if a new element doesn’t solve the problem.
Why Hard Water Causes More Heating Failures
Bath, Wiltshire, and Somerset have very hard water – typically 200-300 mg/l calcium carbonate. This causes significant problems for dishwasher heating elements:
Limescale accelerates element failure
Elements in hard water areas typically fail after 5-7 years compared to 10+ years in soft water areas. The constant heating and cooling cycles cause limescale to build up in thick layers on the element surface, eventually causing the element to overheat internally and burn out.
Salt usage is critical in hard water
Regular dishwasher salt top-ups are essential in Bath and surrounding areas. The water softener needs salt to function – without it, hard water goes straight through to the element causing rapid limescale buildup and heating failure. We see many element failures that could have been prevented with proper salt maintenance.
Prevention tip: Keep salt levels topped up, use rinse aid, and run a maintenance wash with dishwasher cleaner every 1-2 months. Read our dishwasher maintenance guide for more tips on protecting your dishwasher in hard water areas.
How We Diagnose Heating Faults
When you call us for an AEG dishwasher that won’t heat, here’s our diagnostic approach:
1. Test the heating element
We test the element electrically for continuity and earth leakage. We also visually inspect for limescale damage which confirms long-term hard water exposure and accelerated failure.
2. Check sensors and salt system
We verify the temperature and turbidity sensors are functioning correctly. On some AEG models these are combined into a single unit. We also check salt levels and the water softener system is working properly.
3. Verify control board and wiring
If the element tests fine electrically, we check the control board is sending power to the element and all wiring connections are secure.
4. Replace faulty component
Once we’ve identified the cause – usually the heating element – we replace it and advise on proper salt maintenance to prevent future failures.
Most heating repairs are completed in one visit. We carry common heating elements for AEG dishwashers and can source less common ones quickly. Element replacement is one of the more straightforward dishwasher repairs.
AEG Dishwasher Not Heating in Bath or Wiltshire?
We’re dishwasher repair specialists serving Bath, Chippenham, Trowbridge, Keynsham, Melksham, Radstock and surrounding areas of Somerset and Wiltshire. Over 30 years experience with AEG and all major brands. Which? Trusted Traders.
Email: glen@bathwashco.com
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• Dishwasher Maintenance Guide – Preventing heating failures in hard water areas
• Bosch E09 Error Code – Heat pump fault on Bosch dishwashers
• All Dishwasher Repairs – Our main repair services
Which? Trusted Trader