Power The Thermostat; Installing Batteries - Honeywell VisionPRO TB8220 User Manual

POWER THE THERMOSTAT

You can choose from three methods to power the thermostat:
• Batteries only (AAA alkaline).
• 24 Vac direct connection only.
• 24 Vac direct connection with battery backup (AAA alkaline).
Wiring 24 Vac Common
• Single-Transformer System—Connect the common side of
the transformer to the C screw terminal of the thermostat
wallplate. Leave the metal jumper wire in place between Rc
and R.
• Two-Transformer System—Connect the common side of
the cooling transformer to the C screw terminal of the
thermostat wallplate. Remove the metal jumper wire
between Rc and R.

Installing Batteries

1. Install three AAA alkaline batteries on the back of the
thermostat as marked. See Fig. 23.
BATTERIES (3)
Fig. 23. Installing batteries.
2. Locate and remove tab labeled Remove. See Fig. 24.
IMPORTANT
This tab must be removed in order to set the real-time
clock.
REMOVE
TAB
Fig. 24. Remove tab labeled REMOVE from thermostat
TB8220 COMMERCIAL VISIONPRO™ PROGRAMMABLE THERMOSTAT
M19918
M19920
back.
Locate and Mount C7089U Outdoor
Temperature Sensor (Optional)
Mount the sensor where (see Fig. 25):
• cannot tamper with settings.
• there is good air circulation.
• it can measure true outdoor ambient temperature.
• surface is flat.
• wire distance between C7089U and thermostat is less than
200 feet.
Do not mount the sensor:
• in direct sunlight.
• where hot or cold air blows on the sensor. Discharge line
from an outdoor compressor unit, vent or fan causes
inaccurate temperature readings.
• where snow, ice or debris can cover it.
Use the following steps to mount the sensor:
1. Remove the sensor from the mounting clip.
2. Mark the area on the location selected for mounting the
sensor mounting clip.
3. Mount the clip.
Fig. 25. Typical locations for C7089U Outdoor Sensor.
Wire C7089U Outdoor Sensor
CAUTION
Electrical Interference (Noise) Hazard.
Can cause erratic system operation.
Keep wiring at least one foot away from large inductive
loads such as motors, line starters, lighting ballasts and
large power distribution panels.
Use shielded cable to reduce interference when
rerouting is not possible.
9
M7514
63-2625—3