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Troubleshooting
Dead Unit Diagnostics
For dead unit diagnostics, remove the access panels
and locate the power cord connection behind the
EMI
fi
lter on the left side of the unit. Verify power
from the house supply (power cord) by checking for
line voltage on the black to white wires at the EMI
fi
lter. If the house voltage checks O.K. – check for
power coming out of the EMI
fi
lter.
If the house voltage checks good at the EMI
fi
lter,
pull the control board and check for power input to
the main control board at the K101 connector pins
1-2 (black to white). If there is no power check the
wiring connections.
If there is line input to the main board, check for
power output to the power supply. The main board
supplies line power to the power supply board thru
K122 pins 3-5 (black to white). The power supply
then returns DC power to the main board on K123,
12vdc pins 1-3 (brown to black) and 5vdc on pins
2-3 (blue to black). Pin 4 is used for communication
between the boards to activate the FF wall LEDs.