IBC AHU Series - Thermostat Connections

Thermostat connections
Three types of thermostats are compatible with the appliance: conventional, power stealing, and
OpenTherm.
Low Voltage Terminal Description Notes
R 24V power Power to the low voltage
thermostat.
W1 Heating Stage 1
Thermostat connects R to
W1 for first stage heating.
Note: A jumper between W1
and W2 will initiate W2
speed.
W2 Heating Stage 2 Thermostat connects R to
W2 for second stage
heating.
Y1 Cooling Stage 1 Thermostat connects R to
Y1 for first stage cooling.
Y2 Cooling Stage 2 Thermostat connects R to
Y2 for second stage cooling.
G Fan Thermostat connects R to G
to energize fan for ventilation
speed.
C 24V common Common return from the
thermostat – not required for
all thermostats.
T-T
Dry Contacts
Boiler call for heat.
Auxiliary
Com
S1 O/B Reversing valve
Connects to outdoor
appliance on heat pump.
Note: Energized for cooling.
S2 Not used
Compressor
14
Section: Specifications