boiler powered by a genny

[geoff]

So for those who have actually tried it,

how did you get the flame sensing (referenced to earth) to work, or have you referenced it to neutral, or what ?

[John Rumm]

Not tried it, but;

I would have thought you would need to TT the genny... strap neutral to the chassis[1], and an earth stake, 100mA RCD on the output, and then connect the boiler earth to your TT earth.

Making sure the output is floating to start with ;-)

[Andrew Gabriel]

I've tried a Potterton Profile running from an inverter, and that worked fine. System would have still be grounded through all the pipework, and the inverter has neutral and earth internally connected.

[Piers Finlayson]

It just worked for me. Neutral and earth were already connected together inside the generator.

[Roger Mills]

N & E are *not* automatically connected in my genny - the output is fully floating. But I connected them, using a 13A plug with a wire connected between N & E in one of the two outlets, and the extension lead (with an RCD plug on the end) to the boiler in the other outlet.

[I did initially connect them using a large resistor (100w light bulb) rather than a piece of wire - to make sure nothing nasty would happen. I found that N was happy to be strapped to E - with no voltage measurable across the light bulb, so then fitted the bit of wire.]

In order to do this, of course, the boiler has to fed from a conveniently located 13A plug rather than an FCU. I re-wired my heating a while ago to take all its power fron a 13A socket near the boiler rather than from an FCU in the airing cupboard. As John Rumm says, it's also very desirable (necessary even?) to ground the genny chassis using an earth spike. I installed a spike at the same time as re-wiring the boiler.

[geoff]

In message , Roger Mills writes

So, more or less as I expected

cheers