Honeywell Round CT87A - Page 7

CT87A,B,J ROUND® THERMOSTAT
7 69-0274-6
Fig. 8. CT87A for a 2-wire heating only system.
Fig. 9. CT87A for a 3-wire hot water heating only system.
Fig. 10. CT87B for a 4-wire heating/cooling system.
M2018
3
CT87A WALLPLATE
TO
SYSTEM
R
W
Y
POWER
HEAT
M2018
4
WIRE LABELS
(LETTERS
ON ORIGINAL
THERMOSTAT
TERMINALS)
CT87A WALLPLATE
3-WIRE
HOT WATER
ZONE VALVE
R
W
Y
R
B
W
C
O
O
L
•
O
F
F
•
H
E
A
T
F
A
N
O
N
•
A
U
T
O
M2018
5
POWER
CT87B SUBBASE
TO
SYSTE
M
RH G
R
C
W
Y
FAN
HEAT
COOL
JUMPER R
H TO RC