Plumbing

New Triton shower flips the mcb switch when switching on

Anonymous user 23/02/2024 - 3.01 PM

Hi there, I bought a Triton electric shower and my plumber mate fixed it in for me. We've fitted it fine, but found whenever we switch it on it trips the main left bank side mcb in the fusebox. When the power cables are disconnected from the shower the pull cord switches on fine. Also, when we connect it to the shower it lights up fine - only when we turn it to heat water does it throw the mcb. We thought it was a daily shower, but another brand new one does the same when powering on. We've used 10mm2 6242Y cable and a 50 amp BG mcb to feed it, so can't be overloaded. We've also checked every wire for earthing problems, and confident we've not nicked a wire because the shower ceiling pull cord powers on fine. Triton say the main mcb needs to be 80 or 100amp, but mine is 63 amp. Is this likely to be the problem, or should we have used 6242YH spec wire? Is it something in the shower needs resetting? Is has no pcb, so only other thing is the solenoid perhaps? But as we tried 2 brand new showers we doubt it Totally stumped and totally grateful for advice Mark