pappajohn
LIFE MEMBER
I have a bit of a problem and need advise.
It concerns an S plan heating system.
The problem is the heating run continuoisly even with the programmer removed from its back plate.
The room stat has no effect at all.
From what i can see the power is first supplied by the grey wire to both ch and hw port valves (single port spring return) then when either valve is opened via the brown wire (room stat or tank stat) it closes a contact in the respective valve and energises the orange wire which in turn powers the boiler and pump.
If im correct that would constantly power the boiler regardless of stat or programmer if the valve was stuck open.
Am i correct ???
I havent had a proper look at the zone valves yet to see if they have a manual lever due to poor access.
It concerns an S plan heating system.
The problem is the heating run continuoisly even with the programmer removed from its back plate.
The room stat has no effect at all.
From what i can see the power is first supplied by the grey wire to both ch and hw port valves (single port spring return) then when either valve is opened via the brown wire (room stat or tank stat) it closes a contact in the respective valve and energises the orange wire which in turn powers the boiler and pump.
If im correct that would constantly power the boiler regardless of stat or programmer if the valve was stuck open.
Am i correct ???
I havent had a proper look at the zone valves yet to see if they have a manual lever due to poor access.
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