11
TROUBLESHOOTING
Reset Operation
Note:
When thermostat is reset, installer configuration menu settings and programming will reset to factory settings.
If a voltage spike or static discharge blanks out the display or causes erratic thermostat operation, you can reset the thermostat by removing
the wires from terminals R and C (do not short them together) and removing batteries for 2 minutes . After resetting the thermostat, replace the
wires and batteries . If the thermostat has been reset and still does not function correctly contact your heating/cooling service person or place
of purchase .
Symptom
Possible Cause
Corrective Action
No Heat/No Cool/No Fan
(common problems)
1 . Blown fuse or tripped circuit breaker .
2 . Furnace power switch to OFF .
3 . Furnace blower compartment door or
panel loose or not properly installed .
4 . Loose connection to thermostat or system .
Replace fuse or reset breaker .
Turn switch to ON .
Replace door panel in proper position to engage
safety interlock or door switch .
Tighten connections .
No Heat
1 . Pilot light not lit .
2 . Furnace Lock-Out Condition . Heat
may also be intermittent .
3 . Heating system requires service or
thermostat requires replacement .
Re-light pilot .
Many furnaces have safety devices that shut down
when a lock-out condition occurs . If the heat works
intermittently contact the furnace manufacturer or
local HVAC service person for assistance .
Diagnostic:
Set SYSTEM Switch to
HEAT
and
raise the setpoint above room temperature . Within
a few seconds the thermostat should make a soft
click sound . This sound usually indicates the ther-
mostat 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 HVAC service
person to verify the heating is operating correctly .
No Cool
1 . Cooling system requires service or
thermostat requires replacement .
Same 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 .
Heat, Cool or Fan
Runs Constantly
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
.
Check each wire connection to verify they are not
shorted or touching together . No bare wire should
stick out from under terminal block . 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 .
Thermostat Setting &
Thermostat Thermometer
Disagree
1 . Thermostat thermometer setting
requires adjustment .
The thermometer can be ad/- 4 degrees .
See Temperature Display Adjustment in the Con-
figuration Menu section.
Furnace (Air Conditioner)
Cycles Too Fast or Too Slow
(narrow or wide
temperature swing)
1 . The location of the thermostat and/or
the size of the Heating System may
be influencing the cycle rate.
Digital thermostats provide precise control and
cycle faster than older mechanical models . The
system turns on and off more frequently but runs for
a shorter time so there is no increase in energy use .
If you would like an increased cycle time, choose
SL
for slow cycle in the Configuration menu, step 7
(heat) or 8 (cool) . If an acceptable cycle rate is not
achieved, contact a local HVAC service person for
additional suggestions .
Forgot Keypad
Lockout Code
Press the menu button (button will disappear) and
hold in for 20 seconds . This unlocks the thermostat .
