Honeywell T7351F2010 - Digital Thermostat, 3h Installation Instructions Manual page 12

T7351 COMMERCIAL PROGRAMMABLE THERMOSTAT
TR23-H REMOTE SENSOR
1 2 3
SUBBASE
1 2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
1
2
ENSURE TRANSFORMER IS SIZED TO HANDLE THE LOAD.
3 HEAT/COOL SYSTEMS WITH ONE TRANSFORMER REQUIRE THE FACTORY-INSTALLED JUMPER.
4 USE ECONOMIZER INSTRUCTIONS FOR INSTALLATION DIRECTIONS.
5 WHEN USING THE TR23-H FOR HUMIDITY SENSING THERE IS NO NEED TO WIRE HC TERMINAL
BECAUSE THE T3 TERMINAL IS INTERNALLY TIED TO HC, WHICH IS ALSO TIED TO TERMINAL 1
COMMON AT THE SENSOR.
Fig. 9. Typical hookup of T7351F2010 in three-stage heat and three-stage cool conventional system
TROUBLESHOOTING GUIDE (TABLE 7)
Symptom
Display will not Thermostat is not being
come on. powered.
Temperature Thermostat is configured
display is for °F or °C display.
incorrect.
Bad thermostat location.
Display shows three
dashes and a degree sign
(all systems shut down).
Temperature Upper or lower temperature
settings will not limits were reached.
change.
(Example:
Occupied setpoint
Cannot set
temperature range stops
heating higher or
were configured.
cooling lower.)
Keypad is locked. When a
locked key is pressed,
LOCKED appears
momentarily on the LCD.
Room Remote temperature
temperature is sensing is not working.
out of control.
62-0258—05
4 5 6 7 8 9 10 11 12
T5 T6 T7 T4 T3
5
HS HC HP
HUMIDITY
SENSOR
L2
L1
(HOT)
Table 7. Troubleshooting Information.
Possible Cause
OUTDOOR
AIR
SENSOR
DISCHARGE
HEAT
AIR
RELAY 3
SENSOR
OS OS AS AS W3/Y4 Y3
M M X RH RC AUX
3
MOTION
SENSOR
4
ECONOMIZER
with one transformer.
Check that X terminal is connected to the system transformer.
Check for 24 Vac between X and RH terminals.
If missing 24 Vac:
• Check if circuit breaker is tripped; if so, reset circuit breaker.
• Check if system fuse is blown; if so, replace fuse.
• Check if the HVAC equipment power switch is in the Off position; if
so, set to the On position.
• Check wiring between thermostat and HVAC equipment. Replace
broken wires and tighten loose connections.
If 24 Vac is present, proceed with troubleshooting.
Press both Run Schedule and Copy, then reconfigure the display.
Relocate the thermostat.
T7351 is set for remote sensing and sensor is missing or circuit is
either open or shorted.
Check the temperature setpoints:
• Heating limits are 40 to 90°F (7 to 31°C)
• Cooling limits are 45 to 99°F (9 to 37°C)
Check setpoint stops. If necessary, reconfigure the stop(s).
Press both Run Schedule and Copy, then change keypad lock level.
Check all remote sensors.
12
COMPRESSOR
CONTACTOR 2
HEAT
RELAY 2
W2 Y2
W1 Y1 G
COMPRESSOR
CONTACTOR 3
HEAT
FAN
RELAY 1
RELAY
COMPRESSOR
CONTACTOR 1
Action
M29255