DIY Doctor UK DIY Forums

Hi, my central heating system has been coming on upstairs when the heating is supposed to be turned off. I have a wall thermostat downstairs and upstairs. The heating is on a timer and it goes off downstairs when the timer ends but stays on upstairs and the radiators are incredibly hot + I can obviously still hear the boiler working but the lights on the wall panel are off as they should be to indicate that the central heating should not be on.

Does anyone know how to fix this or what is causing the problem as if it was a timer or wall panel problem with the clock, then the heating should stay on in the whole house and not just upstairs and why is it coming on hotter than normal?

I managed to knock the boiler off by moving the timer back round to switch the heating on so the lights on the panel lit up to indicate it was on and then moved it back round to a time to knock it off and this managed to knock the heating off but it has stayed on again today after the heating should have knocked off on the timer and again it is just the upstairs of the house and boiling hot again.

If you have two room thermostats as you have said , i'm imagining there must be at least one 2 port valve on this system, zoned for upstairs and downstairs heating. The actuator/valve is obviously sticking and keeping the heating upstairs on.

What happens if you turn the room thermostat down upstairs ? does it go off ?

If the upstairs room stat is off, and the downstairs one on - do only the downstairs radiators heat up ?

Can you confirm this is the way the system is set up ?