Light on on frost stat when OFCH boiler running

Passport1

Hi
I have an OFCH central heating system.

I have a froststat in the boiler house - not sure what the brand is - it might be a CTL or something like that - see attached

The stat is set to lowest value -5

I've noticed that when the boiler is running either for heating the water or rad heating or for both that the light on the frost stat is on

They light goes off when the heating system is off

I'm assuming thats ok that the light is on on the frost stat as its wired into the system and there nothing to worry about here as power from boiler is causing the light to appear on the frost stat- right?

Thanks

Dtp1979

Passport1 wrote: »

Hi
I have an OFCH central heating system.

I have a froststat in the boiler house - not sure what the brand is - it might be a CTL or something like that - see attached

The stat is set to lowest value -5

I've noticed that when the boiler is running either for heating the water or rad heating or for both that the light on the frost stat is on

They light goes off when the heating system is off

I'm assuming thats ok that the light is on on the frost stat as its wired into the system and there nothing to worry about here as power from boiler is causing the light to appear on the frost stat- right?

Thanks

Ye that's ok. But the stat is set way too low. Set it to 1 degrees, and wire it through a pipestat(set 30) on the return that'll turn the boiler of at that temp. Make sure you've an open loop or bypass fitted inside

Wearb

I would say that your understanding of it is correct. The light may also be comming on because of some very low internal voltage.
Sometime when the system is very cold, leaving the house calls for heat off, turn the frost stat to its highest setting. The light on it should light a good bit brighter.

Passport1

Thanks all for replies and information