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TB7220 ULTRASTAT PROGRAMMABLE THERMOSTAT
63-2636—03 10
Locate and Mount C7089U Outdoor
Temperature Sensor (Optional)
Mount the sensor where (see Fig. 24):
• 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. 24. 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.
1. Wire C7089U Outdoor Sensor to S1 and S2 terminals on
the thermostat. If leadwire provided is not long enough
(60 in.), run a cable to a hole at C7089U location.
a. Using color-coded, 18-gauge thermostat wire is
recommended. For example of general wiring of
C7089U, see Fig. 25.
2. Mount C7089U in its mounting clip.
3. Plug wiring hole using nonhardening caulk or putty.
Fig. 25. Wire C7089U Outdoor Sensor to the thermostat.
Locate and Mount T7770A or C7189U Remote
Indoor Temperature Sensor (Optional)
Locate and mount the sensor in the same fashion as the
thermostat. See the Select Thermostat Location section.
Consider the following as well:
1. Be sure wire distance between sensor and thermostat is
less than 200 feet.
2. Mark the area on the wall selected for mounting the
sensor or junction box.
3. Sensor wire must be separate from the thermostat cable.
4. Run wire cable to a hole at the selected wall location.
5. Pull approximately three inches of wire through the
opening.
NOTE: Color-coded, 18-gauge wire is recommended.
M7514
1
2
2
1
USE APPROPRIATE MOUNTING MEANS FOR THE
TYPE OF STRUCTURE.
PLUG WIRING HOLE WITH NON-HARDENING CAULK
OR PUTTY.
C7089
WIRING HOLE
THROUGH
STRUCTURE
M13664