Troubleshooting – White Rodgers Thermostat 1F78 User Manual
Page 6
www.white-rodgers.com
Symptom
Possible Cause
Corrective Action
Heat, Cool or Fan Runs Constantly.
Possible short in wiring.
1.
Possible short in thermostat.
2.
Possible short in heat/cool/fan system.
3.
FAN Switch set to Fan ON.
4.
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.
Furnace Cycles Too Fast or Too Slow
(narrow or wide temperature swing)
The location of the thermostat and/or the size of
1.
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 accept-
able cycle rate is not achieved as received or by
clipping W-905 contact a local service person for
additional suggestions.
Cooling Cycles Too Fast or Too Slow
(narrow or wide temperature swing)
The location of the thermostat and the size of
1.
the Cooling System can influence the cycle rate.
The cycle rate for cooling is fixed and can not be
adjusted. Contact a local service person for sug-
gestions.
Thermostat Setting and Thermostat
Thermometer Disagree
Thermostat thermometer setting requires adjust-
1.
ment.
The thermometer can be adjusted +/- 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.
7
TROUBLESHOOTING
CONTINUED FROM FIFTH PAGE