Honeywell t7100f Installation Instructions Manual page 8

T7100F MICROELECTRONIC CONVENTIONAL OR HEAT PUMP THERMOSTAT
TROUBLESHOOTING GUIDE (Continued)
Symptom
Heating does not No power to the thermostat.
come on.
Thermostat minimum Off time is
activated and wait indicator is
displayed.
System selection is not set to
Heat.
Cooling does not No power to the thermostat.
come on.
Cooling does not Thermostat minimum Off time is
come on activated and wait indicator is
(continued) displayed.
System selection is not set to
Cool.
System On Fan operation set to 00
indicator is lit, but (conventional heat) when it
no heat is being should be set to 01 (electric
delivered. heat).
Conventional heating
equipment turns on the fan
when the furnace has
warmed up to a setpoint.
Heating equipment is not
operating.
24V is present on When thermostat is powered
all terminals. but is not connected to
heating/cooling equipment, arc
suppression will be present
(24V ghost voltage)
69-0964–2
69-0964–2 D.S. Rev. 12-98 Printed in Taiwan R.O.C.
Possible Cause
• 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 the thermostat and the
HVAC equipment—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 38. Reconfigure minimum On time (if
required).
Set system selection to Heat.
• Check that the 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—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 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.
• Wait up to five minutes for the system to respond.
• Enter Installer Setup 33. Reconfigure minimum Off time (if
required).
Set system selection to Cool.
Enter Installer Setup mode number 02 and reconfigure the fan
operation.
Wait a minute after seeing the On indicator and then check the
registers.
Verify operation of heating equipment in Self-Test.
Connect heating/cooling equipment to the thermostat. Voltage
will drop to zero.
8
Action
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