Immersion Heater and White Meter

[SantaUK]

Hi guys - I went and bought a replacement immersion heater for friends tank. The old immersion heater has two thermostats, and I believe one is fed from the white meter. Only one immersion heater can be fitted to this old copper tank.

I went to Grahams Plumbing for the replacement, and they looked at me as if I had two horns out my head when I asked if they had a direct replacement with two thermostats built in. A plumber that was in the shop at the time, suggested that I wouldn't be able to find an identical replacement for it, or it may be on a shelf in some shop next to the rocking horse shit, and as such, I should just join both live cables into the single thermostat on the new immersion heater. He said that this is what he has done in the past.

Now, I'm just sceptical, I appreciate that he is a plumber, and may be a dam good one at that, but as for the electrics, I would just like to confirm his theory. Does anyone else have a view on this?

Regards

SantaUK

[Andy Wade]

Twaddle, it's a readily available item, e.g.

such, I should just join both live cables into the single thermostat on the

Cowboy alarm! That's potentially a very dangerous thing to do. It could result in the E7 switched supply (if any) being back-fed. Also it could put fuses in parallel and nullify s/c & overload protection, etc.

[NT]

would back feed the entire CU in fact. Really bad idea.

NT

[SantaUK]

And thats why I asked on here! It just didn't ring true. And thats why he aint a sparky.

Many thanks!

[John]

Surely the original concept of two circuits connected through two thermostats is equally wrong. If both stats are making contact (calling for heat) then a reverse current path is made. Such an arrangement should have two separate immersion heaters.

[The Wanderer]

Err, prolly a bad choice of words on the part of the OP. Dual element/dual thermostat immersion heaters are readily available and intended for use on E7 tarrif. See post by Andy Wade above. The long element heats the whole tank overnight, using cheap rate, with the short element providing a top up (not heating the whole tank) if needed during the day.

[SantaUK]

Yes, apologies for the misunderstandning. I believe the original immersion heater actually has two elements, and as such I really need to find a direct replacement. Anyone know of a cheaper alternative rather than the 60+ VAT one quoted?