Installing a nest learning thermostat in the uk use heat link terminals
1,2 and 3. (Or OT which is open therm) Push and hold the button on the
Heat link for 30 seconds, and it should start pulsing blue. On the
thermostat find settings then equipment....
Call the manufacturer ask if third party controls can be fitted to
control the heat pump. Looks like wiring the heat link to the current
thermostat will not work. Needs to be on/off control or open therm
