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T8624C,D
TROUBLESHOOTINGTHERMOSTAT MOUNTED
INCORRECTLY ON BASE.
BATTERIES ARE INCORRECTLY
INSTALLED.
SYMPTOM POSSIBLE CAUSE ACTION
NO ac POWER TO THERMOSTAT CHECK POWER TO FURNACE OR AIR CONDITIONER.
–ON-OFF SWITCH
–FUSE OR CIRCUIT BREAKER
–LOOSE 24V CONNECTION
–AT THERMOSTAT
–AT FURNACE /AIR CONDITIONER
–INCORRECT WIRING
–CHECK WIRING DIAGRAM
FURNACE OR AIR CONDITIONER
WON'T OPERATE. NO ac POWER TO THERMOSTAT CHECK POWER TO FURNACE OR AIR CONDITIONER.
–ON-OFF SWITCH
–FUSE OR CIRCUIT BREAKER
–LOOSE 24V CONNECTION
–AT THERMOSTAT
–AT FURNACE /AIR CONDITIONER
–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.
WAIT 5 -10 MIN. OR USE SELF-TEST IN THERMOSTAT.
SEE CHECKOUT.
MINIMUM-OFF TIMES IN THERMOSTAT
IN OPERATION ON COOLING
INCORRECT WIRING CHECK CIRCUIT DIAGRAM.
FURNACE OR AIR CONDITIONER
INOPERATIVE
CONSULT FURNACE OR AIR CONDITIONER
INSTRUCTIONS.
PARTIAL DISPLAY INOPERATIVE THERMOSTAT REPLACE THERMOSTAT.
CHECK THAT HEAT OR COOL SYSTEM POWER IS ON.NO POWER TO THERMOSTATNO DISPLAY
SEE INSTALLATION INSTRUCTIONS FOR CORRECT
MOUNTING.
PRESENT SETTING APPEARS
INACCURATE. THERMOSTAT IS IN RECOVERY
MODE.
•NORMAL OPERATION THERMOSTAT TURNS ON
HEATING/COOLING EARLY TO MEET TEMPERATURE
SETTING AT PROGRAMMED TIMES.
•RECOVERY CAN BE ENDED BY PUSHING WARMER/
COOLER KEYS.
CANNOT TEMPORARILY OVERRIDE
BOTH HEATING AND COOLING
SETTINGS IN AUTO MODE.
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.
REMOVE AND REPLACE PER MARKINGS ON THERMOSTAT.
REPLACE BATTERIES.
CHECK PROGRAMMING INSTRUCTIONS FOR CORRECT
PROGRAM SEQUENCE.
REPROGRAM ACCORDING PROGRAMMING INSTRUCTIONS
(MAKE SURE BATTERIES ARE INSTALLED).
PROGRAMMING HAS BEEN LOST
BECAUSE OF A POWER OUTAGE.
DISPLAY FLASHES DURING
OPERATION.
DISPLAY FLASHES WHILE
PROGRAMMING. IMPROPER PROGRAM SEQUENCE
PROGRAM IS LOST DUE TO POWER
OUTAGE OR DISPLAY GOES BLANK
WHEN POWER IS TURNED OFF.
BATTERIES ARE DEAD.
M5234A
NOT USING PRESENT SETTING KEY.
SET HEATING AND COOLING TEMPERATURES 3 F OR
MORE APART.
O
ROOM TEMPERATURE DISPLAY
IS 32
˚
F.
PRESS AND HOLD DOWN PRESENT SETTING KEY TO
ALTERNATE BETWEEN HEATING AND COOLING SETTINGS.
AUTOMATIC THERMOSTAT HEATING
OR COOLING TEMPERATURE CAN
NOT BE SET CLOSER THAN 3 F.
O