Immersion heater repair and replacement
Immersion heater elements, thermostats and switches repaired or replaced across South Wales. Fast diagnosis, correct circuit checks and certification.
No hot water from the immersion is normally one of three things: a tripped thermostat, a failed element, or the circuit itself. A failing element also causes RCD trips, so it accounts for a fair share of "the board keeps tripping" calls.
We test rather than assume, and we check the supply and switch as well as the element so the same fault does not return in a month.
- Element, thermostat and switch tested individually
- Circuit and RCD behaviour checked at the board
- Correct heat-resistant flex and double-pole switching
- Certificate issued for any circuit work
Why a failing element trips the RCD
As an element degrades, insulation resistance falls and current leaks to earth. That leakage adds to everything else on the RCD until it trips — often intermittently and usually when hot water is being heated.
The switch and flex matter too
Immersion switches sit in hot cupboards and degrade. Heat-damaged switches and hardened flex are common, and replacing the element while leaving those in place is a false economy.
Twin elements and cylinder type
Some cylinders have two elements at different heights, and unvented cylinders have specific requirements. We identify the cylinder type before ordering parts.
Common questions
Can you replace the element the same visit?
Often yes, where the cylinder type is standard and accessible.
Why does my hot water trip the electrics?
Most commonly a degraded immersion element leaking to earth. Testing confirms it in minutes.
Do you drain the cylinder?
Element replacement requires draining down; we allow for that in the quote.
Get a fixed price
Losing hot water and tripping the board at the same time? Mention both when you call — it usually points straight at the element.