TB8220 COMMERCIAL VISIONPRO™ PROGRAMMABLE THERMOSTAT
63-2625—3
6
Table 5. Terminal Designation Descriptions.
NOTES:
1.
When used in a single-transformer system, leave
metal jumper wire in place between Rc and R. If
used on a two-transformer system, remove metal
jumper wire between Rc and R.
2.
Common wire is optional when thermostat is used
with batteries. When using separate transformers
for heating and cooling, the common must come
from the cooling transformer.
3.
If thermostat is configured for a heat pump in the
Installer Setup, configure changeover valve for
cool (O-factory setting) or heat (B).
4.
Reference economizer literature for wiring details.
When set for economizer operation, the A terminal
provides the occupancy signal. (Power indicates
occupied.)
5.
Sensor wires must have a cable separate from the
thermostat control cable.
Terminal “A” Wiring Details for Economizers
— Wire the A terminal to the W7212 “N” terminal, or the
W7459 “TR” terminal.
— When using dual transformers at the thermostat, the
heating transformer must power the economizer.
— The A signal is powered from the R terminal and energizes
the economizer to signal occupied status and drive the
damper to the set minimum position.
Conventional System Wiring
Fig. 12. Typical wiring of single transformer 1H/1C system.
Fig. 13. Typical hookup of dual transformer 1H/1C system.
Terminal
Designation
Description
Rc
(see Note 1)
Power for cooling—connect to secondary side
of cooling system transformer.
R
(see Note 1)
Power for heating—connect to secondary side
of heating system transformer.
Y
Compressor output.
C
(see Note 2)
Common wire from secondary side of cooling
system transformer.
W
Heat relay.
G
Fan relay.
W2
Second stage heat relay.
Y2
Second stage cooling.
O/B
(see Note 3)
Changeover valve for heat pumps.
A
(see Note 4)
Economizer/Time-Of-Day (TOD) output—
powered via R terminal.
S1
(See Note 5)
Optional outdoor or indoor remote sensor.
S2
(See Note 5)
Optional outdoor or indoor remote sensor.
L
Powers red LED behind plastic in upper right
corner of the thermostat.
COMPRESSOR CONTACTOR
M22781A
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
HEAT RELAY
ECONOMIZER
FAN RELAY
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
FACTORY INSTALLED JUMPER.
WHEN USING BATTERIES, THE 24V COMMON CONNECTION
IS OPTIONAL.
1
2
3
Y2
L
A
W2
S1
S2
2
3
RC
R
W
Y
G
C
L1
(HOT)
L2
1
24 VAC
COMPRESSOR CONTACTOR
M22782A
OUTDOOR/INDOOR
TEMPERATURE
SENSOR
HEAT RELAY
FAN RELAY
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
REMOVE FACTORY INSTALLED JUMPER.
WHEN USING BATTERIES, THE 24V COMMON CONNECTION
IS OPTIONAL. WHEN USED, THE COMMON MUST CONNECT
TO THE COOLING TRANSFORMER SECONDARY.
1
3
2
3
2
Y2
L
A
W2
S1
S2
2
RC
R
W
Y
G
C
ECONOMIZER
L1
(HOT)
L2
1
24 VAC
L1
(HOT)
L2
1
24 VAC
