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8.7- TROUBLESHOOTING
8.7.1- System lockout
When a system lockout occurs (1 hour), the gas valve is de-energized, the
low speed inducer blower is energized for the 60 seconds inter-purge
period and the circulator is energized for selected heat off delay if it was
previously ON. The diagnostic indicator light will flash the fault that is
present (refer to diagnostic table).
To reset the control after system lockout, do one of the following:
8.7.2- System reset
Remove 24 VAC power to the control for twenty (20) seconds
or longer to reset the control.
8.7.3- Thermostat reset
Remove the call for heat from the thermostat for a period of between (1)
second and less 20 seconds. If flame is sensed with the gas valve de-
energized, interrupting the call for heat at the thermostat will not reset the
control.
8.7.4- Auto restart
After one (1) hour of internal or external lockout, the control will
automatically reset itself and go into an auto restart purge for 15 seconds.
8.7.5- Diagnostic features
The control continuously monitors its own operation and the operation of
the system. If a failure occurs the diagnostic indicator LED (DSI) will flash
a “RED” failure code. If a failure is internal to the control the “RED”
indicator will stay on continuously. In this case, the entire control should
be replaced as the control is not field-repairable. If the LED is continuously
OFF, there may be no power to the control or a failure within the control.
If the sensed failure is in the system (external to the control), the LED will
flash RED in the sequence listed in the Diagnostic Table. The LED will
also indicate “System Status” as per the Amber and Green LED signatures
listed in the Diagnostic Table. The LED will flash one RED flash at power
up.
8.7.6- Fault code retrieval
To retrieve fault codes, push and release the “LAST ERROR” button for
more than 1/5 seconds and less than 5 seconds. (Control will indicate this
period by solid GREEN for 1/5 seconds. to 5 seconds). The LED will flash
up to five stored fault codes, beginning with the most recent. If there are
no fault codes in memory, the LED will flash two green flashes. The control
will flash the most recent error first and the oldest error last (last in first
out). There shall be 2 seconds between codes. Solid LED error codes will
not be displayed.
NOTE: These error codes may be different from furnace
label or furnace manual.
8.7.7- CFM indicator
The LED (DS2) CFM flashes when the blower motor is running. The
flashing indicates the motor CFM (cubic feet per minute) air flow
designated by the furnace manufacturer. Consult the furnace
manufacturer for flash code detail.
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