Earth cable to a bathroom radiator... how critical?

[Cheekster247]

So I'm partway through decorating my new place and have discovered an earth cable which runs all the way from behind the main fuse box, around the edge off the living room carpet, across the front of the stairs, into the kitchen and up through the ceiling to the bathroom radiator. I need to level the uneven floor downstairs before laying laminate and the cable is going to be a bit of a pain because of the way it's been routed.

How critical is having the bathroom radiator earthed in this way? None of the others are at all.

[Tye Green]

do you have copper pipes ?

[Cheekster247]

Unfortunately so. Older house so it's mainly copper throughout. None of the others are earthed though, but I'm presuming it's needed because of the proximity to water etc in the bathroom?

[Mr Pointy]

Are all circuits - especially any serving the bathroom - protected by a 30mA RCD?

[OutInTheShed]

Cheekster247 said:

So I'm partway through decorating my new place and have discovered an earth cable which runs all the way from behind the main fuse box, around the edge off the living room carpet, across the front of the stairs, into the kitchen and up through the ceiling to the bathroom radiator. I need to level the uneven floor downstairs before laying laminate and the cable is going to be a bit of a pain because of the way it's been routed.

How critical is having the bathroom radiator earthed in this way? None of the others are at all.

You want your plumbing bonded to your mains ground, but it doesn't have to be done in the bathroom.
If all the plumbing is continuous copper, bonding it anywhere should be enough.
Normally it's done at the boiler.

If somebody has messed with the plumbing of that bathroom rad, using plastic 'cheat's plumbing', so it's no longer electrically connected to the rest of the CH system, then it may require bonding. more so if it has a towel heater element in it.

This is my opinion based on a knowledge of electricity, which is not the same as knowing the latest regs!!!
I ain't no 'lectrishun...

Some body has added that wire for a reason.
Likely reasons might include strange interpretation of the regs, or someone feeling a voltage difference between the rad and some other metal in the bathroom. Been there, not pleasant!

Proper answer would be to check out the earthing, bonding and wiring generally.
Best do this before any decorating etc!
You really don't want to be told your wiring is duff after you've laid a floor, painted walls etc.

[Mr Pointy]

OutInTheShed said:

Some body has added that wire for a reason.
Likely reasons might include strange interpretation of the regs, or someone feeling a voltage difference between the rad and some other metal in the bathroom. Been there, not pleasant!

It's possible that previous versions of the regs did require supplementary bonding but that is no longer emphasised especially if the piping is copper (& properly bonded at a visible point) & the bathroom circuits are RCD protected. Personally if they are I'd remove the cable. Similarly you don't seem to see any emphasis on bonding kitchen sinks & taps these days.

[OutInTheShed]

I'm reluctant to advise removal of an earth without appropriate acts of poking about with a multimeter.

[dhutch]

I presume you are not doing any re-wiring at the time. Did you get an EICR when you bought the place?
Maybe get whoever did that, or a-another local spark in to advise?

[Little Lofty]

It’s an old reg that was only around for a shortish period of time, I remember when all the pipes to a boiler were cross bonded too, in fact just about bloody everything was earthed. That doesn’t mean you can rip it out though, other criteria has to be met I believe. Ideally you’ll need an electrician to take a look.

[Cheekster247]

Cheers all I'll leave it where it is and work around it. To answer all the questions, yes there are RCDs in place for all the bathroom electrics (lights and boiler separately). The bathroom rad is furthest away from the main board, so why that one is specifically earthed over the one literally two foot away is a bit of a mystery but I suppose it's better being safe than sorry and just leave it as it is.

[Little Lofty]

Cheekster247 said:

Cheers all I'll leave it where it is and work around it. To answer all the questions, yes there are RCDs in place for all the bathroom electrics (lights and boiler separately). The bathroom rad is furthest away from the main board, so why that one is specifically earthed over the one literally two foot away is a bit of a mystery but I suppose it's better being safe than sorry and just leave it as it is.

As far as I remember it was only the bathroom rad that needed the earth.