Immersion Heater Reset

The 'Why'

No hot water from an immersion heater usually means a tripped circuit, the wall switch is off, or the thermal cut-out has tripped (e.g. thermostat stuck or element overheating). Most failures are simple resets - but repeated tripping signals a faulty element or thermostat.

The 5-Minute Fix

• Check the consumer unit: Look for Immersion, Hot Water, or Cylinder circuit. If tripped, switch firmly to ON. If it trips again immediately, stop - there is a fault.
• Check the wall switch: Usually near the cylinder (e.g. airing cupboard). Ensure it is ON. Loose or non-staying switches may need replacing.
• Reset the cut-out: Some immersions have a thermal cut-out with a red reset under a flap. Isolate power, wait 10 minutes to cool, press reset, restore power. If it trips again quickly, element or thermostat has likely failed.

When it's more than a simple reset

If the reset trips again or water stays cold, likely causes include:

• Burnt-out heating element - common in older cylinders; requires replacement by a qualified electrician.
• Faulty thermostat - stuck open or failed; needs testing and replacement.
• Thermal cut-out failure - repeated tripping indicates overheating; element or wiring fault.

For immersion diagnostics and repairs, contact Thanet Electrical for a fixed-price check.