Troubleshooting guide

APPENDIX B
B-3
TABLE B-2. FAULT MESSAGES - Continued
FAULT MESSAGE FAULT DESCRIPTION
RESIDUAL
FLAME
The Flame signal was seen for more than 60 seconds during
standby.
HEAT DEMAND
FAILURE
The Heat Demand Relays on the Ignition board failed to
activate when commanded.
IGN BOARD
COMM FAULT
A communication fault has occurred between the PMC board
and Ignition board.
DIRECT DRIVE
SIGNAL FAULT
The direct drive signal is not present or is out of range.
REMOTE SETPT
SIGNAL FAULT
The remote setpoint signal is not present or is out of range.
OUTDOOR TEMP
SENSOR FAULT
The temperature measured by the Outdoor Air Sensor is out
of range.
OUTLET TEMP
SENSOR FAULT
The temperature measured by the Outlet Sensor is out of
range.
FFWD TEMP
SENSOR FAULT
The temperature measured by the FFWD Sensor is out of
range.
HIGH WATER
TEMPERATURE
The temperature measured by the Outlet Sensor exceeded
the Temp Hi Limit setting.
LINE VOLTAGE
OUT OF PHASE
The High AC voltage is out of phase from the low AC voltage.
STEPPER MOTOR
FAILURE
The stepper motor failed to move the valve to the desired
position.
NETWORK COMM
FAULT
The RS-485 network information is not present or is
corrupted.