Honeywell T7300F Installation Instructions Manual page 11

TROUBLESHOOTING GUIDE (Continued).
Symptom
Heating does not
turn on.
Cooling does not
turn on.
System on
indicator (flame=heat,
snowflake=cool) is
displayed, but no
warm or cool air is
coming from the
registers.
24 Vac across all
terminals.
T7300F SERIES 2000 COMMERCIAL MICROELECTRONIC CONVENTIONAL
Possible Cause
No power to the thermostat.
Thermostat minimum off -
time is activated and wait
indicator is displayed.
System selection is not set
to Heat.
No power to the thermostat.
Thermostat minimum off -
time is activated and wait
indicator is displayed.
System selection is not set
to Cool.
Conventional heating
equipment turns on the fan
when the furnace has
warmed up to a setpoint.
Heating or cooling equipment
is not operating.
This is an arc suppression
voltage. Placing a load on
the terminal drops the
voltage to zero.
• Check that the 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; if so, reset
the circuit breaker.
— check if the system fuse is blown; if so, replace
the fuse.
— check if the system switch at the equipment is in
the Off position; if so, set to the On position.
— check wiring between thermostat and HVAC
equipment and replace any broken wires and
tighten any loose connections.
— If 24 Vac is present, proceed with troubleshooting.
• Wait up to five minutes for the system to respond.
• Enter Installer Setup number 38. Reconfigure minimum
off-time (if required).
Set system selection to Heat.
• Check that X terminal is connected to the system
transformer.
• Check for 24 Vac between X and R or RC and Y
terminals.
— If missing 24 Vac:
— check if the circuit breaker is tripped; if so, reset
the circuit breaker.
— check if the system fuse is blown; if so, replace
the fuse.
— check if the system switch at the equipment is in
the Off position; if so, set to the On position.
— check wiring between thermostat and HVAC
equipment and replace any broken wires and
tighten any loose connections.
— If 24 Vac is present, proceed with troubleshooting.
• Wait up to five minutes for the system to respond.
• Enter Installer Setup number 33. Reconfigure minimum
off-time (if required).
Set system selection to Cool.
Wait one minute after the on indicator lights and then
check the registers.
Verify operation of heating or cooling equipment in self -
test.
No action.
11
OR HEAT PUMP THERMOSTAT
Action
62-0125—3