Wiring - Honeywell TH8321 Product Data

VISIONPRO® 8000 SMART THERMOSTAT

WIRING

Conventional System
Terminal
C Common wire from secondary side of cooling
transformer (if 2 transformers).
Rc* Cooling power
R* Heating power
W Heat Stage 1
W2 Heat Stage 2
Y Compressor Stage 1
Y2 Compressor Stage 2
G Fan Relay
A Connect to Economizer Module or Lighting Panel
(TOD).
U1 / U1 Relay for humidification, dehumidification,
ventilation, economizer control, with fault, or a
stage of heating/cooling.
S1 / S1 Input for a wired indoor, outdoor or discharge
sensor.
Connect to K on C-wire adapter
†
K
* Remove factory installed jumper for two transformer systems.
†
The THP9045A1098 C-wire adapter is used on heat/cool systems when you only have four wires at the thermostat and
you would like the thermostat to be powered with a common wire. Use the K terminal in place of the Y and G terminals on
conventional or heat pump systems to provide control of the fan and the compressor through a single wire—the unused
wire then becomes your common wire. See page 85 and the THP9045 instructions (form 33-00342) for more information.
CAUTION
Electrical Hazard.
Can cause electrical shock or equipment damage.
Disconnect power before wiring.
All wiring must comply with local electrical codes and
ordinances. See Fig. 225–234.
1. Select wiring diagram that corresponds with system
type and the equipment being installed.
2. Loosen the screws for the appropriate terminals.
Insert wires in the terminal block under the loosened
screw. See Fig. 222.
3. Securely tighten each screw.
4. Push excess wire back into the hole.
5. Plug the hole with nonflammable insulation to pre-
vent drafts from affecting the thermostat.
6. See Fig. 225–234 for typical wiring hookups.
33-00096—04
Table 9. Thermostat Terminal Designation Descriptions.
Description Terminal
C Common wire from secondary side of cooling
transformer.
Rc Cooling power
R Heating power
O / B Changeover valve for heat pumps
AUX-E Backup Heat/Emergency Heat
Y Compressor Stage 1
Y2 Compressor Stage 2
G Fan Relay
L / A Connect to Compressor Monitor, Zone Panel,
Economizer Module or Lighting Panel (TOD).
U1 / U1 Relay for humidification, dehumidification,
ventilation, economizer control, with fault, or a
stage of heating/cooling.
S1 / S1 Input for a wired indoor, outdoor or discharge
sensor.
Connect to K on C-wire adapter
†
K
C
K
RC
R
U1
U1
U2
U2
Fig. 222. Inserting wires in thermostat terminal block.
IMPORTANT
Use 18–22 gauge thermostat wire.
84
Heat Pump
Description
CONVENTIONAL
S1 S1
S1 S1
W O/B
Y Y
G G
W2 AUX
-E
Y2
Y2
A
L/A
HEAT PUMP