Shower tripping RCD?

lookitsjonno · 10 Feb 2019 at 14:10

My shower keeps randomly tripping my 50A RCD. This first happened when the shower was on, but it also tripped when the shower was turned off.

I replaced the pull switch on the ceiling last year and that still looks healthy. I've isolated and removed the cover and everything looks as it should, nothing burned out etc.

Since it trips when the shower is off I'm hopeful it could be a quick fix, switch, solenoid etc. Any suggestions?

bremen1874 · 10 Feb 2019 at 14:43

How do you know it's the shower tripping it?

Does the shower have its own dedicated RCD?

On my fairly typical consumer unit each RCD protects a number of different circuits and any one of (or a combination of) them could cause an RCD to trip.

lookitsjonno · 10 Feb 2019 at 14:51

I disconnected the shower from the isolation switch and it no longer trips

bremen1874 · 10 Feb 2019 at 15:00

So I'd say that you've either got a faulty shower or an overly sensitive RCD.

Electrical devices with water heating elements are the classic for tripping RCDs.

lookitsjonno · 10 Feb 2019 at 15:04

Never thought of dodgy RCD

Yes, I'd agree with heating element if it only tripped while in the shower.

Steampunk · 10 Feb 2019 at 23:29

I had the same problem. After you get out of the shower, you get a heat soak effect as cold water is no longer running through it, and that trips the thermal protection a couple of minutes later, tripping the RCD. It turned out for me the fault was the RCD, and swapping it with a replacement fixed the issue.

You can tell by looking at the RCD and seeing if it trips more easily than others, and clicks less positively into its on positions. Mine was almost trembling, and the barest touch would trip it open.