Hi,
I have replaced an old honewell analogue room thermostat with a honeywell CM 901 digital programmable one. Previously unless the main central heating timer was set to ON the heating would not come on no matter what temperature the stat was set to - as you would expect. HOWEVER now i have the new digital stat installed the central heating comes on even if it is set to off on the main central heating timer. In theory this will still work but I find it really weird and cannot understand how the heating can come on when the main control panel is set to off.... can anyone explain?
In terms of wiring there were 3 wires previously but the new stat only required 2 so i blanked off the neutral connection which i beleive is no longer required.
Thanks
Marc
I have replaced an old honewell analogue room thermostat with a honeywell CM 901 digital programmable one. Previously unless the main central heating timer was set to ON the heating would not come on no matter what temperature the stat was set to - as you would expect. HOWEVER now i have the new digital stat installed the central heating comes on even if it is set to off on the main central heating timer. In theory this will still work but I find it really weird and cannot understand how the heating can come on when the main control panel is set to off.... can anyone explain?
In terms of wiring there were 3 wires previously but the new stat only required 2 so i blanked off the neutral connection which i beleive is no longer required.
Thanks
Marc
