Boiler switching on by itself!

[rocky_robin]

Firstly, the boiler is a old Camray oil boiler. 90/110 or something like that.

Anyway, the hot water tank is Santon main pressurised.
No room stats nor any TRV's on the rad's (will be upgrading to these in the summer)

The programmer is CL Lifestyle LP520

During the week, we have the boiler going for the hot water and CH.
At the weekends however, we have the coal fire going to heat the house up and the boiler to operate the HT once a day. The tank is in the living room beside the fire.

However, these past 2 weekends, the pumps have started running below the tank (they vibrate) and the boiler kicks in mins later, even though the programmer is off!!

No rads get hot, so must not be circulating, which is fine (as its flipping hot with the fire going!!)

I've had to switch the suystem off at the wall to shut the boiler off.

Is the boiler getting confused with the heat from the fire, or is the boiler firing cause the hot water tank is getting cold, or am I missing the point somewhere?

Any help would be great.

Thanks in advance!

 

[Agile]

Is the boiler outside somehow with a frost stat operating???

Tony

 

[rocky_robin]

Thanks for the reply.

Yes the boiler is outside.
I switched it back on before going to bed and the boiler kicked in again.

Having read quite a few threads on here and opened the cupboard and manually switched off the CH valve. That shut down the boiler & pump.

I'll have to look at the boiler. Been a novice at boilers, I'm gonna have to do some amount of reading first.