Troubleshooting - Honeywell CHRONOTHERM III T8611M User Manual

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.
S YMPTOM
HEAT PUMP OR AUXILIARY HEAT
WON'T OPERATE
PARTIAL DISPLAY
NO DISPLAY
PRESENT SETTING APPEARS
INACCURATE
ROOM TEMPERATURE DISPLAY
APPEARS INACCURATE
ROOM TEMPERATURE IS NOT WHAT
IS EXPECTED ON WEEKENDS
THERMOSTAT TEMPERATURE
NEEDS TO BE ADJUSTED ON A
REGULAR BASIS
PROGRAM IS LOST DUE TO POWER
OUTAGE OR DISPLAY GOES BLANK
WHEN POWER IS TURNED OFF
DISPLAY FLASHES WHILE
PROGRAMMING
DISPLAY FLASHES DURING
OPERATION
POS S IBLE C AU S E
NO ac POWER TO THERMOSTAT
THERMOSTAT INOPERATIVE
PRESENT SETTING TOO LOW/HIGH
SYSTEM SWITCH ON THERMOSTAT IN
WRONG POSITION
MINIMUM-OFF TIMES IN THERMOSTAT IN
OPERATION ON COOLING OR HEATING
INCORRECT WIRING
HEAT PUMP OR AUXILIARY HEAT SYSTEM
INOPERATIVE
INOPERATIVE THERMOSTAT
NO POWER TO THERMOSTAT
THERMOSTAT IN SELF-TEST MODE
THERMOSTAT MOUNTED INCORRECTLY
ON BASE
THERMOSTAT IS IN RECOVERY MODE
THERMOSTAT HAS SEPARATE REMOTE-
MOUNTED SENSOR
THERMOSTAT NOT PROGRAMMED FOR
WEEKENDS
WARMER/COOLER KEYS BEING USED
TO ADJUST TEMPERATURE
BATTERIES ARE INCORRECTLY INSTALLED
BATTERIES ARE DEAD
IMPROPER PROGRAM SEQUENCE
AUTOMATIC CHANGEOVER THERMOSTAT
HEATING OR COOLING TEMPERATURES
CAN NOT BE SET CLOSER THAN 3°F
PROGRAMMING HAS BEEN LOST BECAUSE OF
A POWER OUTAGE
29

Troubleshooting

AC TION
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
CONDUCT SELF-TEST; SEE CHECKOUT.
ADJUST TEMPERATURE BY PUSHING WARMER/COOLER
KEYS.
RESET THERMOSTAT SYSTEM SWITCH.
WAIT 5-10 MIN. OR USE SELF-TEST IN THERMOSTAT.
SEE CHECKOUT.
CHECK CIRCUIT DIAGRAM.
CONSULT HEAT PUMP/AUXILIARY HEAT SYSTEM
INSTRUCTIONS.
REPLACE THERMOSTAT.
CHECK THAT HEAT OR COOL SYSTEM POWER IS ON.
PRESS RUN PROGRAM KEY TWICE.
SEE INSTALLATION INSTRUCTIONS FOR CORRECT
MOUNTING.
• NORMAL OPERATION THERMOSTAT TURNS ON
HEATING/COOLING EARLY TO MEET TEMPERATURE
SETTING AT PROGRAMMED TIMES.
• RECOVERY CAN BE ENDED BY PUSHING
WARMER/COOLER KEYS.
•
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.
REPROGRAM FOR WEEKENDS PER INSTRUCTIONS.
REPROGRAM THERMOSTAT TO MAKE PERMANENT
CHANGE IN PROGRAM. WARMER/ COOLER KEYS ARE
TEMPORARY UNLESS PERIOD KEY IS PRESSED FIRST.
REMOVE AND REPLACE PER MARKINGS ON THERMOSTAT.
REPLACE BATTERIES.
CHECK HOMEOWNERS MANUAL FOR CORRECT PROGRAM
SEQUENCE.
SET HEATING AND COOLING TEMPERATURES 3°F OR
MORE APART.
REPROGRAM ACCORDING TO PROGRAMMING
INSTRUCTIONS (MAKE SURE BATTERIES ARE INSTALLED).
T8611M

TROUBLESHOOTING

M1020A
68-0076—1