Computer Board - A.O. Smith Water Heater 520 Direct Vent Indoor Service Manual

10-18. Computer board

Unit Part #
Function
Failure events
Effects on the water
heater if the computer
board fails
Error codes when the
computer board fails
Diagnostic
Color/Number of wires
#701 AOS Part #
Controls the functions of most of the parts in the water heater.
Malfunctioning computer
-A component(s) may not operate within the water heater. In most cases
of computer board failure, the whole the water heater does not operate at
all.
-Error codes display.
701 711
Visual inspection: connection/breakage of wires and/or burn marks on the
computer board.
520 Indoor / 520 Outdoor Service Manual
319143-126
721
N/A
36
CONFIDENTIAL
Ver. 1.00
Checkpoint N/A
741 761