OK, I have a Back boiler, Pumped CH and Gravity Hot water system.
Controller is a Horstmann H21
the other week I found that the fuse to the system had blown, and after killing a couple of fuses I found that the wall Thermostat had died. Replaced that and thought all was ok, but have since found that the hot water doesn't appear to work...
Basically the controller will let you try to schedule, advance or boost the HW, but the LED to indicate that the HW is on comes on, but very dimly, sometimes flickers a little, but it never seems to actually kick the boiler off (and presumably doesn't open the valve either).
My suspicion is that something in the controller is fried but before I replace that (at not inconsiderable expense), Does anyone have any other suggestions for this? Since the operation of the HW light is not connected - If I recall correctly - to the actual operation of the boiler or the tank 'stat (if HW is 'ON' then the light is ON regardless of whether it thinks the temperature of the HW in the tank warrants the boiler/valve being open), then I don't think a faulty tank stat or zone valve should cause this... and the CH works fine.
I intend to check that all connections are secure to the back of the controller, but need to work out how to get into it first... (no obvious screws, only looked at it for a couple of mins last night)
Anyone seen something like this? Anything obvious I've missed?
Cheers
Controller is a Horstmann H21
the other week I found that the fuse to the system had blown, and after killing a couple of fuses I found that the wall Thermostat had died. Replaced that and thought all was ok, but have since found that the hot water doesn't appear to work...
Basically the controller will let you try to schedule, advance or boost the HW, but the LED to indicate that the HW is on comes on, but very dimly, sometimes flickers a little, but it never seems to actually kick the boiler off (and presumably doesn't open the valve either).
My suspicion is that something in the controller is fried but before I replace that (at not inconsiderable expense), Does anyone have any other suggestions for this? Since the operation of the HW light is not connected - If I recall correctly - to the actual operation of the boiler or the tank 'stat (if HW is 'ON' then the light is ON regardless of whether it thinks the temperature of the HW in the tank warrants the boiler/valve being open), then I don't think a faulty tank stat or zone valve should cause this... and the CH works fine.
I intend to check that all connections are secure to the back of the controller, but need to work out how to get into it first... (no obvious screws, only looked at it for a couple of mins last night)
Anyone seen something like this? Anything obvious I've missed?
Cheers
