Troubleshooting – Honeywell CHRONOTHERM III T8611M User Manual
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Troubleshooting
HEAT PUMP OR AUXILIARY HEAT
WON'T OPERATE
NO ac POWER TO THERMOSTAT
CHECK POWER TO HEAT PUMP OR
AUXILIARY HEATING SYSTEM
–ON-OFF SWITCH
–FUSE OR CIRCUIT BREAKER
–LOOSE 24 V CONNECTION
-AT THERMOSTAT
-AT HEAT PUMP OR AUXILIARY HEATING SYSTEM
–INCORRECT WIRING
-CHECK WIRING DIAGRAM
THERMOSTAT INOPERATIVE
CONDUCT SELF-TEST; SEE CHECKOUT.
PRESENT SETTING TOO LOW/HIGH
ADJUST TEMPERATURE BY PUSHING WARMER/COOLER
KEYS.
SYSTEM SWITCH ON THERMOSTAT IN
WRONG POSITION
RESET THERMOSTAT SYSTEM SWITCH.
MINIMUM-OFF TIMES IN THERMOSTAT IN
OPERATION ON COOLING OR HEATING
WAIT 5-10 MIN. OR USE SELF-TEST IN THERMOSTAT.
SEE CHECKOUT.
INCORRECT WIRING
CHECK CIRCUIT DIAGRAM.
HEAT PUMP OR AUXILIARY HEAT SYSTEM
INOPERATIVE
CONSULT HEAT PUMP/AUXILIARY HEAT SYSTEM
INSTRUCTIONS.
S YMPTOM
POS S IBLE C AU S E
AC TION
PARTIAL DISPLAY
INOPERATIVE THERMOSTAT
REPLACE THERMOSTAT.
NO DISPLAY
NO POWER TO THERMOSTAT
CHECK THAT HEAT OR COOL SYSTEM POWER IS ON.
THERMOSTAT IN SELF-TEST MODE
PRESS RUN PROGRAM KEY TWICE.
THERMOSTAT MOUNTED INCORRECTLY
ON BASE
SEE INSTALLATION INSTRUCTIONS FOR CORRECT
MOUNTING.
PRESENT SETTING APPEARS
INACCURATE
THERMOSTAT IS IN RECOVERY MODE
•
•
ROOM TEMPERATURE IS NOT WHAT
IS EXPECTED ON WEEKENDS
THERMOSTAT NOT PROGRAMMED FOR
WEEKENDS
REPROGRAM FOR WEEKENDS PER INSTRUCTIONS.
THERMOSTAT TEMPERATURE
NEEDS TO BE ADJUSTED ON A
REGULAR BASIS
WARMER/COOLER KEYS BEING USED
TO ADJUST TEMPERATURE
REPROGRAM THERMOSTAT TO MAKE PERMANENT
CHANGE IN PROGRAM. WARMER/ COOLER KEYS ARE
TEMPORARY UNLESS PERIOD KEY IS PRESSED FIRST.
PROGRAM IS LOST DUE TO POWER
OUTAGE OR DISPLAY GOES BLANK
WHEN POWER IS TURNED OFF
BATTERIES ARE INCORRECTLY INSTALLED
REMOVE AND REPLACE PER MARKINGS ON THERMOSTAT.
BATTERIES ARE DEAD
REPLACE BATTERIES.
DISPLAY FLASHES WHILE
PROGRAMMING
IMPROPER PROGRAM SEQUENCE
CHECK HOMEOWNERS MANUAL FOR CORRECT PROGRAM
SEQUENCE.
AUTOMATIC CHANGEOVER THERMOSTAT
HEATING OR COOLING TEMPERATURES
CAN NOT BE SET CLOSER THAN 3°F
SET HEATING AND COOLING TEMPERATURES 3°F OR
MORE APART.
DISPLAY FLASHES DURING
OPERATION
PROGRAMMING HAS BEEN LOST BECAUSE OF
A POWER OUTAGE
REPROGRAM ACCORDING TO PROGRAMMING
INSTRUCTIONS (MAKE SURE BATTERIES ARE INSTALLED).
NORMAL OPERATION THERMOSTAT TURNS ON
HEATING/COOLING EARLY TO MEET TEMPERATURE
SETTING AT PROGRAMMED TIMES.
RECOVERY CAN BE ENDED BY PUSHING
WARMER/COOLER KEYS.
M1020A
ROOM TEMPERATURE DISPLAY
APPEARS INACCURATE
THERMOSTAT HAS SEPARATE REMOTE-
MOUNTED SENSOR
•
•
•
THERMOSTAT IS CONTROLLED BY TEMPERATURE SENSED
AT REMOTE SENSOR LOCATION.
CHECK TEMPERATURE AT REMOTE SENSOR LOCATION.
MAKE SURE WIRING FROM THERMOSTAT LOCATION TO
REMOTE SENSOR LOCATION IS IN GOOD CONDITION.
Start the system by setting the thermostat and observing system response. If problem occurs, establish symptom and use
the following troubleshooting chart to check for possible cause and action.
T8611M
TROUBLESHOOTING