CT500 ELECTRONIC THERMOSTAT
7
69-1525—2
10 TROUBLESHOOTING
See Table 3 to troubleshoot your thermostat.
Table 3. Troubleshooting Your Thermostat.
Symptom
Possible Cause
Corrective Action
Heating/cooling
equipment does not
operate.
No power to the
thermostat.
Check power to heating/cooling equipment:
— On/Off switch.
— Fuse or circuit breaker.
— Loose 24V connection: at thermostat; at furnace/air
conditioner.
— Incorrect wiring; check appropriate wiring diagram.
System switch on
thermostat not in
correct position.
Reset System switch.
Thermostat minimum-
off times operating for
cooling.
Wait five minutes.
Incorrect wiring.
Check wiring.
Heating/cooling
equipment not
operating.
Consult equipment manfacturer instructions.
Partial display.
Thermostat not
operating.
Replace thermostat.
Remained in customize
mode.
See Customize Your Thermostat section to exit this mode.
No display.
No power to thermostat.
Check power to thermostat.
Thermostat mounted
incorrectly on wallplate.
See Mount Thermostat to Wallplate section.
Temperature display
is incorrect.
Thermostat is
configured for °F or °C.
Reconfigure the display. See Customize Your Thermostat
section for instructions to change the display.
Cannot change
temperature setting.
The upper or lower
temperature limits were
reached.
Check the temperature setpoints; temperature setting range is
40°F (4°C) to 99°F (37°C).
Snowflake is
flashing.
Cooling equipment
turns on after delay.
Wait approximately five minutes after the indicator starts flashing
and then check the registers.
System on indicator
(flame=heat) is
displayed, but no
warm air is coming
from the registers.
Heating equipment
turns on the fan when
the furnace has
warmed up to a
setpoint.
Wait a minute after seeing the on indicator and then check the
registers. If still no heat is coming from the registers, call your
local heating and/or cooling contractor.