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Symptom
Possible Cause
Corrective Action
No Heat
(common problems)
Blown fuse or tripped circuit breaker.
1.
Furnace power switch to OFF.
2.
Furnace blower compartment door or panel
3.
loose or not properly installed.
Replace fuse or reset breaker.
Turn switch to ON.
Replace door panel in proper position to engage safety interlock or door switch.
No Heat
Pilot light not lit.
1.
SYSTEM Switch not set to
2.
HEAT
.
Loose connection to thermostat or system.
3.
Furnace Lock-Out Condition. Heat may also be
4.
intermittent.
Heating system requires service or thermostat
5.
requires replacement.
Re-light pilot.
Set SYSTEM Switch to
HEAT
and raise temperature above room temperature.
Verify thermostat and system wires are securely attached.
Many furnaces have safety devices that shutdown when a lock-out condition
occurs. If the heat works intermittently contact the furnace manufacturer or local
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 thermostat is operating properly. If the thermo-
stat 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 manufac-
turer or a service person to verify the heating is operating correctly.
Heat, Runs
Constantly
Possible short in wiring.
1.
Possible short in thermostat.
2.
Possible short in heat system.
3.
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 system for
correct operation. If the system operates correctly, replace the thermostat.
Furnace Cycles Too
Fast or Too Slow
(narrow or wide
temperature swing)
The location of the thermostat and/or the
1.
size of the Heating System may be
influencing the cycle rate.
Digital thermostats normally provide precise temperature 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, clip Jumper
W-905 as mentioned in the instructions for Hydronic Heating Systems. It is not
possible to shorten the cycle time. If an acceptable cycle rate is not achieved
as received or by clipping W-905 contact a local service person for additional
suggestions.
Thermostat Setting and
Thermostat Thermometer
Disagree
Thermostat thermometer setting requires
1.
adjustment.
The thermometer can be ad/- 3 degrees. See Temperature Display
Adjustment in the Operation section.
Blank Display and/or
Keypad Not Responding
Voltage spike or static discharge.
1.
Battery change required.
2.
Replace batteries and check heat/cool system for proper operation. If a voltage
spike occurs use the Reset Operation listed above.
ELECTRICAL DATA
Electrical Rating:
0 to 30 VAC 50/60 Hz. or D.C.
0.05 to 1.0 Amps (Load per terminal)
1.5 Amps Maximum Total Load
(All terminals combined)
THERMAL DATA
Setpoint Temperature Range:
45°F to 90°F (7°C to 32°C)
Operating Ambient Temperature Range:
32°F to 105°F
Operating Humidity Range:
0 to 90% RH (non-condensing)
Shipping Temperature Range:
-40°F to 150°F
Reset Operation
If a voltage spike or static discharge blanks out the display or
causes erratic thermostat operation you can reset the thermostat
by pressing
and
at the same time while moving the
SYSTEM switch from
OFF
to
HEAT
. This also resets the factory
defaults. If the thermostat has power, has been reset
and still does not function correctly contact your heating/cooling
service person or place of purchase.
Batteries
For optimum performance, we recommend replacing batteries
once a year with fresh “AAA” Energizer
®
alkaline batteries.
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SPECIFICATIONS
7
TROUBLESHOOTING
White-Rodgers is a division
of Emerson Electric Co.
The Emerson logo is a
trademark and service mark
of Emerson Electric Co.
Homeowner Help Line: 1-800-284-2925
www.white-rodgers.com
www.emersonclimate.com