Newish boiler but old wiring to thermostat

TornAtTheShoulder

Please ignore my last question! The black wire is doubled back, that's all!

Myser

Be careful while poking around inside the thermostat. If wired to the boiler, one of those wires will be permanent live!

TornAtTheShoulder

It's a Honeywell Thermostat T6360B1028. I googled for info and came across wiring diagrams. I think I've bothered you enough with this though. I clearly need to have a look what's been done between the boiler and the unit.

TornAtTheShoulder

I will switch off at the mains!

Myser

TornAtTheShoulder wrote: »

I clearly need to have a look what's been done between the boiler and the unit.

You should start by looking at the boiler connections rather than suspecting in between. You can check the integrity of the wiring between the boiler and the thermostat using a multimeter which will only cost you around £5.

:exclamatiDon't go prodding around if you aren't competent though!

Myser

TornAtTheShoulder wrote: »

I will switch off at the mains!

There should be a dedicated isolation FCU (Fused Connection Unit) for the boiler wiring/controls. It should look something like this:

TornAtTheShoulder

Oh yes! There is but I didn't know what it was for. I'll still switch off at the mains though. And thanks for your advice - I'm VERY wary of electrical stuff but do try to fix things if I can. Probably not in this case! :-)

Myser

The reason why I suggested using the dedicated isolation switch is because if you switch off the mains to the circuit or the whole house, you may have to go round resetting all the clocks etc.

TornAtTheShoulder

That's thoughtful but I there is actually nothing in my house that would be affected by the mains being off! But I'd do it anyway, I'd be too scared not to.

TornAtTheShoulder

I've been looking at multimeters on Ebay. Can you recommend one that's simple to use or are they all much the same?