Info request

[Nick]

I think I can see the point that you are possibly making... that is that the socket (assumed to be a double or have a multiway adaptor plugged in) may be "overloaded".

A boiler will take perhaps 250 watts - say 1 amp and the heater may take another

12 amps or so - that's not more than 16A, and certainly not more than a ring with a 32A CCT breaker protecting it. The possible likely event is that the breaker might trip but that is not "dangerous" (is it ?) The same can happen at every other double socket in the house ! I suppose the boiler would not function if the circuit was tripped out so it might be cold.

I really can't see why this is "dangerous" !

Nick

[John White]

[...]

No, sorry, you're missing the point.

I'm not concerned about the socket being overloaded. The MCB would protect the cable assuming it had been specified correctly at the design stage. Like fuses, MCBs protect the cable and not the appliance.

What I am concerned about is there being (in the example I gave) a socket installed in a bathroom. This is definitely a bad idea - as well as being prohibited by the regs. In this case there was not even a RCD as a backup safety device.

One flat had a hairdryer plugged into the socket and lying on the glass shelf over the basin. Sooner or later somebody will knock it into the basin, and then reach into the water to pull it out...

If the boiler was wired into a FCU then the socket would not have been available to be abused in the first place.

On a PIR I would (and did) flag up such an installation as being unsafe and requiring immediate attention.

John

[Nick]

Oh, absolutely - you naturally see many more installations than I do, and I can understand and completely agree that such an installation should be (is) definitely not permitted, nor should it be done by any D-I-Yer for just that very reason.

One day the house will be sold and almost certainly to someone who doesn't appreciate the danger quite apart from the fact that the installation should not give the opportunity for the danger to arise in the first place.

Thanks for the example

Nick

[Nick]

After considering all replies, I think I will arrange for there to be a SWA cable laid underground from the CU in the house, to a small CU in the garage, with an RCD within, and the lights / power fed from this.

The house system is TN-S ..... would it be correct for the earth to be exported, or kept separate and derived from a local spike, just bringing out live and neutral. ?

Thanks,

Nick