Electric shower keeps tripping the circuit breaker (Triton & Mira)
⚠️ This needs a qualified professional
This fault involves gas or mains electrical work. Don't attempt a DIY repair — UK law requires gas work to be carried out by a Gas Safe registered engineer. Below is what to check and describe to them, not step-by-step repair instructions.
A circuit breaker that trips specifically when the shower is switched on — rather than randomly, or affecting other circuits — is a clear, useful diagnostic signal. It almost always points to a genuine electrical fault in the shower unit itself, not general house wiring.
What’s safe to check yourself
- Confirm it really is the shower’s dedicated circuit tripping, not a coincidence with something else switching on at the same time (an immersion heater or other high-draw appliance on the same circuit, if incorrectly shared).
- Check the breaker is rated correctly for the shower’s power rating (shown on the shower unit’s rating plate, typically 7.5kW-10.5kW for most UK homes) — an undersized breaker relative to the shower will trip under normal use, which is a wiring issue rather than a fault with the shower itself.
- Note whether it trips immediately on switch-on, or only after running for a while — immediate tripping points more towards a short circuit or earth fault; tripping after a delay can suggest the element overheating.
⚠️ Do not keep resetting the breaker
A breaker that trips repeatedly when switching on an electric shower is very likely protecting you from a genuine fault — most commonly a failing heating element or water ingress into the electrical housing. Do not keep resetting it and trying again, and don’t open the shower unit casing. This needs a qualified electrician, and given it involves a fixed bathroom electrical installation, any repair work falls under UK Part P building regulations.