7
009-1593-02
Two Power Source Wiring
o
G
Y2
Y1
W2
W1
RC
RH
TX+
T
X-
24
C
Power wire (Rc)
from HVAC
cooling.
Common (C)
wire from HVAC.
Power wire (R)
from HVAC
heating.
RH
Supplies power to the relays connected to terminals
W1, W2, and O.
RC
Supplies power to the relays connected to terminals
Y1, Y2, and G.
24C
Common terminal. The common (C) wire from HVAC
system is required for thermostat to run.
Additional Powering Schemes
Jumper Shunt - JP1
If the HVAC system uses separate power sources to run the
heating and cooling, you should have three wires labeled for
power (R, C, and RC). In this scenario, remove the jumper
shunt from JP1. The next section describes this.
Jumper JP1 on the thermostat board connects the RH and RC
terminals. The thermostat is shipped from the factory with a
jumper shunt installed. For systems with more than one power
source, remove the jumper shunt.
RH
REMOVE SHUNT
24
C
RC
JP1
Powers Relays
W1, W2, and O.
Powers Relays
Y1, Y2, and G.
IMPORTANT!
Remove
jumper shunt from JP1
if more than one power
source is used. Failure
to remove the shunt will
result in damage to the
thermostat.