1. Failed Heating Element (Most Common)

The heating element is an electrical component submerged in the water that 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. This is by far the most common cause of washing machines not heating, especially in hard water areas like Bath and Wiltshire where limescale accelerates element failure.

When elements fail, they can also trip the fusebox or RCD. If your fusebox trips when the washing machine starts a hot wash, a faulty heating element is the likely cause.

2. Faulty Thermistor (Temperature Sensor)

The thermistor (also called NTC sensor) monitors water temperature and tells the control board when to switch the heating element on and off. If the thermistor fails, the control board doesn’t know the water is cold, so it never activates the heating element. Less common than element failure but still a regular cause we see.

3. Limescale Buildup on Element

In hard water areas, limescale builds up on the heating element surface. Heavy limescale coating insulates the element, preventing efficient heat transfer to the water. The element might still work electrically but can’t heat the water properly. Eventually, the extra stress from limescale causes the element to fail completely.

4. Control Board or Wiring Fault

The main control board sends power to the heating element. If the board develops a fault or there’s damaged wiring between the board and element, 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.

5. Incorrect Program Selected

Before assuming a fault, check you’ve selected a hot wash program. Eco programs and quick washes often use cold or lukewarm water only to save energy. If every program runs cold including dedicated hot cycles (60°C, 90°C), then there’s a genuine fault.

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 layers on the element surface, eventually causing the element to overheat internally and burn out.

Visual signs of limescale damage

When we remove failed elements from machines in Bath and surrounding areas, they’re often completely encased in thick white limescale. A healthy element should be smooth metal; a failed one from hard water looks like it’s covered in chalky rock.

Prevention tip: Using limescale prevention products (descaler in every wash or regular maintenance washes) can extend element life in hard water areas. We’ve seen machines with original elements still working after 12+ years when owners have been diligent about limescale prevention.

1. Test the heating element

We test the element electrically for continuity and earth leakage. A failed element shows either no continuity (open circuit) or leaks to earth. We also visually inspect for limescale damage which confirms long-term hard water exposure and accelerated failure.

2. Check thermistor and wiring

If the element tests fine electrically, we check the thermistor sensor and verify all wiring connections are secure. We also check the control board is sending power to the element.

3. Replace faulty component

Once we’ve identified the cause – usually the heating element – we replace it. Most heating repairs are completed in one visit.

Most heating repairs are completed in one visit. We carry common heating elements for major brands and can source less common ones quickly. Element replacement is one of the more straightforward washing machine repairs.