nest Learning thermostat, Installation Manual, Page: 12 / 144

3. Connect to the thermostat wires
Skip to the next step if you’re installing the
Nest Thermostat on the stand and are using
the USB cable for power .
Take two wires from the wire bundle that goes
to the current thermostat and attach them to
the T1 and T2 terminals on the Heat Link .
Installing the Heat Link
HEATING
Call-for-heat (normally open)
Common
Satisfied (normally closed)
12 V DC power
Earth
OpenTherm (42 V DC max)
HOT WATER
Call-for-heat (normally open)
Common
Satisfied (normally closed)
230 V AC live and neutral
input power
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