ICM Controls SC2000L Installation, Operation & Application Manual page 10

4-Wire, Single Transformer
Transformer
HOT
120 VAC 24 VAC

Heating/Cooling
Pre-Installed Jumper
RH
RC
Heating
W
Control
Cooling
Y
Control
B
O
Fan
G
Control
SC2000
RH RC
HOT
120 VAC
T
(Heating)
H
Transformer
E
R
M
O
S
T
A
T
HOT
120 VAC
(Cooling)
Transformer
Note: Both transformers must be in phase
5-Wire, Two Transformer
Pre-Installed
24 VAC
Heating
Control
Cooling
Control
24 VAC
Fan
Control
RH RC
Remove
Jumper
RH
RC
T
H
E
W
R
M
Y
O
S
T
B
A
T
O
G