TROUBLESHOOTING
Symptom
No Heat (continued)
No Cool
Heat, Cool or Fan
Runs Constantly
Possible Cause
Furnace
(Air Conditioner)
Cycles Too Fast
or Too Slow (narrow or
wide temperature swing)
5. Heating system requires service or
thermostat requires replacement.
(continued)
1. SYSTEM button not pressed to COOL.
Thermostat Setting &
Thermostat Thermometer
Disagree
Blank Display and/or
Keypad Not Responding
Heat Setpoint will
not Respond to the
Temperature Up Key
Cool Setpoint will
not Respond to the
Temperature Down Key
Forgot Keypad
Lockout Code
2. Loose connection to thermostat or
system.
3. Cooling system requires service or
thermostat requires replacement.
1. Possible short in wiring.
2. Possible short in thermostat.
3. Possible short in heat/cool/fan
system.
4. FAN Switch set to Fan On.
1. The location of the thermostat and/or
the size of the Heating System may
be influencing the cycle rate.
1. Thermostat thermometer setting
requires adjustment.
1. Voltage spike or static discharge.
1. The desired setpoint conflicts with the
setpoint of the COOL mode.
1. The desired setpoint conflicts with the
setpoint of the HEAT mode.
Corrective Action
sound. This sound usually indicates the thermostat
is operating properly. If the thermostat does not
click, try the reset operation listed above. If the
thermostat does not click after being reset contact
your heating and cooling service person or place of
purchase for a replacement. If the thermostat clicks,
contact the furnace manufacturer or a service
person to verify the heating isoperating correctly.
Press SYSTEM button to COOL and lower setpoint
below room temperature.
Verify thermostat and system wires are securely
attached.
Same procedure as diagnostic for No Heat condition
except set the thermostat to COOL and lower the
setpoint below the room temperature. There may be
up to a five minute delay before the thermostat clicks
in Cooling.
Check each wire connection to verify they are not
shorted or touching together. No bare wire should
stick out from under terminal screws. Try resetting
the thermostat as described above. If the condition
persists the manufacturer of your system or service
person can instruct you on how to test the Heat/Cool
system for correct operation. If the system operates
correctly, replace the thermostat.
Digital thermostats normally provide precise tem-
perature control and may cycle faster than some
older mechanical models. A faster cycle rate means
the unit turns on and off more frequently but runs for
a shorter time so there is no increase in energy use.
If you would like to increase the cycle time, choose
SL for slow cycle in the menu, step 4. If an accept-
able cycle rate is not achieved as received or by
choosing slow cycle, contact a local service person
for additional suggestions.
The thermometer can be adjusted +/- 4 degrees.
See Temperature Display Adjustment in the Configu-
ration Menu section.
Use the Reset Operation at top of previous page.
Change system mode to COOL. Raise the Cool
setpoint. Return to HEAT mode and set desired
temperature.
Change system mode to HEAT. Lower the Heat
setpoint. Return to COOL mode and set desired
temperature.
CAUTION: This resets the thermostat to factory
default settings of the configuration menu. After
performing this reset, the thermostat will require
configuration again. Be sure that you know the
required configuration settings before resetting.
With the thermostat in any mode, press Q and (£) at
the same time to enter the configuration menu at the
point where the lockout code is to be entered. Press
11