Honeywell T8524, Product Data, Page: 13 / 16

T8524 DELUXE ELECTRONIC THERMOSTAT
68-0202
13
Symptom Possible Cause Action
Temperature settings will
not change. (Example:
Cannot set the heating
The upper or lower
temperature limits were
reached. Check the temperature setpoints:
•
Heating limits are 45°F to 88°F (7°C to 31°C)
• Cooling limits are 48°F to 99°F (9°C to 37°C).
higher or the cooling lower.) The setpoint
temperature range
stops were configured.
Check Installer Setup numbers 34 and 35 and reconfigure the setpoint
stops.
Heating will not come on. No power to the
thermostat. • Check that C terminal is connected to the system transformer.
• Check for 24 Vac between C 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.
System selection is not
set to Heat. Set system selection to Heat.
Cooling will not come on. No power to the
thermostat. • Check that C terminal is connected to the system transformer.
• Check for 24 Vac between C 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.
Thermostat minimum off
time is activated. • Wait up to five minutes for the system to respond.
• Enter Installer Setup mode number 33. Reconfigure minimum off
time (if required).
System selection is not
set to Cool. Set system selection to Cool.
System On indicator is lit,
but no heat is being
delivered. Heating equipment is
not operating. Verify operation of heating equipment in system test.
Outdoor temperature
not displayed
(select
models)
Option not activated. Enter Installer Setup number 24 and set to 1. Thermostat must have
OT terminals and a C7089B1000 installed.
Outdoor temperature
Outdoor sensor is
connected incorrectly. Refer to C7089B1000 installation instructions and check wiring
between the thermostat and sensor.
Display is incorrect (select
models)
Wrong sensor. Replace sensor with C7089B1000 sensor.