thanks for the response. To I need to link the SCR 1 and 3 wires together? Or can I remove completely?
I read on another thread about doing this. (But removing completely is much easier)
I want to replace the existing LP822 and wireless thermostat and thought the backplate wiring was identical. However there are no connections for H or HW OFF. So advice would be great.
System boiler and cylinder.
photos are attached.