Frost Stat on CH System ??

[self builder 123]

Hi

I have a Grant oil fired condensing boiler.

I have a frost stat wired to the boiler. I understand that if the frost stat activates that it over rides the clock setting and powers up the CH system. This assumes that there is power to the boiler.

I have the on off switch on the front of the boiler switched to off, but found that the frost stat over rides this as well ?

Is this normal ? I was wondering what might happen if someone was servicing the boiler on a cold day and assumed that the on off switch on the front of the boiler had electrically isolated it ?

Any help would be appreciated.

Cheers

 

[ollski]

It can be normal, electrical isolation is done from the fused spur not an on / off switch.