Hello,
I'm trying to replace a conventional Drayton central heating programmer with the above Viessmann wireless programmer, in my Viessmann 100W system boiler.
I have a Y plan setup, and am unsure how I can get the programmer to output to the 3 port valve to call for CH or DHW. Does anyone have a wiring diagram that may be of help, as the boiler wiring diagram is next to useless, and the programmer just tells me to clip it in to port X7!
Any help would be appreciated.
Many thanks.
I'm trying to replace a conventional Drayton central heating programmer with the above Viessmann wireless programmer, in my Viessmann 100W system boiler.
I have a Y plan setup, and am unsure how I can get the programmer to output to the 3 port valve to call for CH or DHW. Does anyone have a wiring diagram that may be of help, as the boiler wiring diagram is next to useless, and the programmer just tells me to clip it in to port X7!
Any help would be appreciated.
Many thanks.