Honeywell T8601D, Installation Instructions Manual

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T8601D CHRONOTHERM® IV DELUXE PROGRAMMABLE THERMOSTATS
9 69-1626
Table 6. Troubleshooting Guide.
Symptom Possible Cause Action
Display does not
come on. Thermostat is not being
powered • Check that C terminal is connected to the system transformer.
• Check for 24 Vac between R and C 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 connec-
tions.
—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.
Temperature
settings do not
change.
(Example: Cannot
set the heating
higher or the
cooling lower.)
The upper or lower
temperature limits were
reached.
Check the temperature setpoints:
• Heating limits are 40 to 90°F (4.5 to 32°C)
• Cooling limits are 48 to 99°F (7 to 35°C
The setpoint temperature
range stops were
configured.
Check Installer Setup numbers 34 and 35 and reconfigure the
setpoint stops.
Heating does
come on. No power to the
thermostat. • Check that C terminal is connected to the system transformer.
• Check for 24 Vac between R and W 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 connec-
tions.
—If 24 Vac is present, proceed with troubleshooting.
Thermostat minimum off
time is activated.
Wait up to five minutes for the system to respond.
System selection is not set
to Heat.
Set system selection to Heat.
Heating setpoint is below
room temperature.
Check heating setpoint. Set heating setpoint to desired temperature.
Cooling does not
come on.
No power to the
thermostat.
• Check that C terminal is connected to the system transformer.
• Check for 24 Vac between R and W 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 connec-
tions.
—If 24 Vac is present, proceed with troubleshooting.
Thermostat minimum off
time is activated.
• Wait up to five minutes for the system to respond.
• Enter Installer Setup number 33. Reconfigure minimum off time (if
required).
System selection is not set
to Cool. Set system selection to Cool.
Cool setpoint is above
room temperature. Check cooling setpoint. Set cooling setpoint to desired temperature.