T7200D,E, T7300D,E,F AND Q7300 SERIES 2000 PROGRAMMABLE COMMERCIAL THERMOSTATS AND SUBBASES
63-4355—1
24
Table 14. 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 R or RH terminals.
—
If missing 24 Vac:
—
check if the circuit breaker is tripped—reset the circuit
breaker.
—
check if the system fuse is blown—replace the fuse.
—
check if the power switch on the HVAC equipment is
in the Off position—set to the On position.
—
check wiring between thermostat and HVAC
equipment—replace any broken wires and tighten any
loose connections.
—
If 24 Vac is present, proceed with troubleshooting.
Temperature display is
incorrect.
Room temperature display has
been reconfigured.
Enter Installer Setup number 37 and reconfigure the display.
Thermostat is configured for
°
F or
°
C display.
Enter Installer Setup number 14 and reconfigure the display.
Bad thermostat location.
Relocate the thermostat.
Display shows two dashes and a
degree sign.
Installer Setup 22 is set for remote sensing and the sensor is
missing or the circuit is open or shorted.
Temperature settings
will not change.
(Example: Cannot
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)
set heating higher or
cooling lower.)
The setpoint temperature range
stops were configured.
Check Installer Setup number 34 and 35 and reconfigure the
setpoint stops.
Keypad is locked. When a locked
key is pressed, LOC will flash on
the LCD.
•
Reset DIP switch 1 on back of thermostat to enable keypad.
•
Enter Installer Setup number 25 or 40 and reconfigure keypad
lockout level.
Unable to configure
Installer Setup
Installer Setup is locked out
Reset the DIP switch 1 on back of thermostat to enable keypad.
Temperature settings
change from original
setting.
Trying to set heating and cooling
setpoints too close together. There
is a deadband in automatic
changeover thermostat models.
Example: cool setpoint=72,
deadband=3, heat setpoint=68,
changing heat setpoint to 70 will
automatically change the cool
setpoint to 73.
•
Check that the heating setpoint is lower than the cooling
setpoint.
•
Check Installer Setup number 30 to identify the deadband
between heating and cooling setpoints. Reconfigure if
desired.
Room temperature is
out of control.
Remote temperature sensing is
not working.
Checkout all remote sensors.
Heating will not come
on.
No power to the thermostat.
•
Check that X terminal is connected to the system transformer.
•
Check for 24 Vac between X and R or RH terminals.
—
If missing 24 Vac:
—
check if the circuit breaker is tripped—reset the circuit
breaker.
—
check if the system fuse is blown—replace the fuse.
—
check if the system switch at the equipment is in the
Off position—set to On position.
—
check wiring between thermostat and HVAC
equipment—replace any broken wires and tighten any
loose connections.
—
If 24 Vac is present, proceed with troubleshooting.
(Continued)
