nest Learning thermostat - Testing Advanced Heating Stages; Switching Operational Modes; Heat Pump Lockout Temperature Settings; Adjusting Heat Pump Valve Orientation

OpenTherm boiler
L
N
OT boiler
N L 1 2 3 4 5 6 OT1 OT2 T1 T2
OT1 OT2
Input power
12 V
3 A
230 V AC/50 Hz
24