Hi all,
My friend has recently bought a house with a load of problems with the central heating but before I go into all of them, I was hoping one of you could help me with a relatively simple problem.
The heating system is an S-type system with 2 x two port valves, a British Gas UP1 controller and a British Gas RS1 room thermostat (see pic).
Once the heating is switched on from the controller, it stays on, even if you turn it off from the controller. I've worked out that this is likely to be a stuck valve.
However, the room thermostat does nothing at all, i.e. it doesn't "click" when turned. I've tried replacing it for a new Drayton RTSI 2400I Room Thermostat but that doesn't "click" either.
My question is, although the stuck valve would render the room thermostat useless, surely it should still "click" if it was wired correctly? And if not, can someone tell me why not please?
Thank you in advance for your responses. Below I have provided information about additional testing I have completed, in case it is useful...
I opened up the room thermostat (see pic) and used my voltage tester to determine the following:
i) When the controller has no mains power from the FCU, there is a no voltage between L and N, nor between the yellow wire (Switched Live) and either L or N.
ii) When the controller has mains power from the FCU but the heating is Off at the controller there is a voltage of 12v between L and N. Nothing between the yellow wire (SL) and either L or N.
ii) When the heating is turned on at the controller, there is a voltage of 230v between L and N but nothing between (SL) and N (I guess this is two be expected since the thermostat hasn't been switched as the cover is off).
My friend has recently bought a house with a load of problems with the central heating but before I go into all of them, I was hoping one of you could help me with a relatively simple problem.
The heating system is an S-type system with 2 x two port valves, a British Gas UP1 controller and a British Gas RS1 room thermostat (see pic).
Once the heating is switched on from the controller, it stays on, even if you turn it off from the controller. I've worked out that this is likely to be a stuck valve.
However, the room thermostat does nothing at all, i.e. it doesn't "click" when turned. I've tried replacing it for a new Drayton RTSI 2400I Room Thermostat but that doesn't "click" either.
My question is, although the stuck valve would render the room thermostat useless, surely it should still "click" if it was wired correctly? And if not, can someone tell me why not please?
Thank you in advance for your responses. Below I have provided information about additional testing I have completed, in case it is useful...
I opened up the room thermostat (see pic) and used my voltage tester to determine the following:
i) When the controller has no mains power from the FCU, there is a no voltage between L and N, nor between the yellow wire (Switched Live) and either L or N.
ii) When the controller has mains power from the FCU but the heating is Off at the controller there is a voltage of 12v between L and N. Nothing between the yellow wire (SL) and either L or N.
ii) When the heating is turned on at the controller, there is a voltage of 230v between L and N but nothing between (SL) and N (I guess this is two be expected since the thermostat hasn't been switched as the cover is off).
