7
Symptom
Possible Cause
Corrective Action
No Heat/
No Cool/
No Fan
(common problem)
1.)
Blown fuse or tripped circuit
breaker
2.)
Furnace power switch to OFF
3.)
Furnace blower compartment
door panel loose or not properly
installed
4.)
Loose connection to thermostat
or system
1.)
Replace fuse or reset breaker
2.)
Turn switch to ON
3.)
Replace door panel in proper position to
engage safety interlock or door switch
4.)
Tighten Connections
No Heat
1.)
System Switch not set to Heat
2.)
Loose connection to thermostat
or system
3.)
Heating System requires
service or thermostat requires
replacement
Verify thermostat and system wires are securely
attached.
Diagnostic: Set System Switch to Heat and raise
the setpoint above room temperature. Within five
minutes the thermostat should make a soft click
sound and “Heat On” should appear on display.
This sound indicates the thermostat is operating
properly. If the thermostat does not click, try
the reset operation listed after this charting.
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 system is operating correctly.
No Cool
1.)
System Switch not set to Cool
2.)
Loose connection to thermostat
or system
3.)
Cooling System requires
service or thermostat requires
replacement
Verify thermostat and system wires are securely
attached.
Diagnostic: Set System Switch to Cool and
lower setpoint below room temperature. Same
procedures 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 if the compressor lock-out option
is selected in the installer menu. (see INSTALLER
MENU, item 50)
Heat, Cool or Fan
Runs Constantly
Possible short in wiring, thermostat,
heat, cool or fan system
Check each wire connection to verify they are not
shorted or touching other wires. Try resetting the
thermostat. If the condition persists contact your
HVAC service person.
Thermostat
Display &
Thermometer
Disagree
Thermostat display requires
adjustment
Display can be ad/-
5
°. See User Menu
item
04
(Troubleshooting continued on next page)
TROUBLESHOOTING
Resetting the Thermostat or Thermostat Settings
If the thermostat has good batteries, but has a blank display or does not respond to key
presses, the thermostat should be reset by removing the batteries for
2
minutes. This reset
will not change the menu settings or program. If the condition persists after reinstalling the
batteries, replace the thermostat.
To conveniently reset only the schedule and user settings back to factory defaults, press Menu
and Backlight buttons at the same time and hold until the display goes blank and resets.
HOMEOWNER HELP LINE:
1-800-284-2925
White-Rodgers is a business
of Emerson Electric Co.
The Emerson logo is a
trademark and service mark
of Emerson Electric Co.
www.white-rodgers.com
www.emersonclimate.com
TROUBLESHOOTING (C0ntinued)
Symptom
Possible Cause
Corrective Action
Furnace (Air
Conditioner)
Cycles Too Fast or
Slow (narrow or
wide temperature
swing)
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. If you would like to increase
cycle time, choose SLO for slow cycle in the
Installer menu. (Reference menu items
30 & 35
) If
an acceptable cycle rate is not achieved, contact
your HVAC service person.
“Call for Service”
icon appears on
displayed
1.)
Heating system is not able to heat
the space to within
10
degrees of
the setpoint within
2
hours
2.)
Cooling system is not able to cool
the space to within
10
degrees of
the setpoint within
2
hours
3.)
If “--” is displayed for the Room
Temperature, a replacement
thermostat is needed
4.)
None of the buttons operate on
the thermostat
5.)
If “Call for Service” is flashing,
compressor self diagnostic is
detecting an issue with the
outdoor unit
1.)
See corrective action for “No Heat”
2.)
See corrective action for “No Cool”
3.)
Replace thermostat
4.)
Make sure keypad lockout is not turned on
(denoted by icon)
5.)
Contact a service person to verify the
equipment is operating correctly
