T7350 COMMERCIAL PROGRAMMABLE THERMOSTAT
23 63-2605—5
TROUBLESHOOTING GUIDE (TABLE 19)Table 19. Troubleshooting Information.
Symptom Possible Cause Action
Display will not come on. Thermostat is not being powered. Check that X terminal is connected to the system
transformer.
Check for 24 Vac between X and RH or RC 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.
Temperature display is
incorrect.
Room temperature display has been
recalibrated.
Use PDA configuration software to recalibrate as desired.
Thermostat is configured for °F or °C
display.
Press both Run Schedule and Copy, then reconfigure the
display.
Bad thermostat location. Relocate the thermostat.
Display shows three dashes and a degree
sign (all systems shut down).
T7350 is set for remote sensing and sensor is missing or
circuit is either open or shorted.
Temperature settings will
not change.
(Example: Cannot set
heating higher or cooling
lower.)
Upper or lower temperature limits were
reached.
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)
Occupied setpoint temperature range
stops were configured.
Using a PDA, check setpoint stops. If necessary,
reconfigure the stop(s).
Keypad is locked. When a locked key is
pressed, LOCKED appears momentarily
on the LCD.
•Use PDA (Set, Display) to unlock keypad.
•Press both Run Schedule and Copy, then change
keypad lock level.
Room temperature is out
of control.
Remote temperature sensing is not
working.
Check all remote sensors.
Heat will not come on. No po wer to the thermostat. 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.
Thermostat minimum off time is activated. •Wait up to five minutes for the system to respond.
•Use PDA to configure heating response.
System selection is set to Off or Cool. Set system selection to Heat or Auto.
DAT high limit has been reached, or
OAT lockout is engaged.
•If the setpoints are correct, do nothing.
•Use PDA (Heating Config) to adjust or disable DAT
high limit and/or OAT lockout.
•Check HVAC equipment to ensure proper operation.