Displaying Error Codes - A.O. Smith T-M50 ASME Service Manual

12-2. Displaying error codes

If the T-M50 is undergoing abnormal conditions, the computer will display the error code to indicate the
source of the problem. The error codes are displayed on the 7-seg LED of the central computer board
and on the remote controller. Please note that error codes are displayed differently, depending on where
its being read, and whether it is a single-unit installation or a multi-unit installation.
A. With a single-unit installation:
Example: If your unit fails on the "321" error (inlet thermistor)
・ Central computer board: The 7-Seg LED will flash the 3-digit error code one digit at a time. The 7-Seg
LED will display "3"... "2"... "1" and will continually repeat these 3 digits.
When the right and/or left combustion section has an error code, the red lamp next to the 7-Seg LED
on the central computer board will flash to indicate which combustion section has the error code.
Refer to the pictures below.
・Remote controller: The remote controller, however, will display "321" on its screen, in its entirety.
Central computer board)
T-M50 / T-M50 ASME Service Manual
7-Seg LED
51
CONFIDENTIAL
Ver. 1.05
The top red lamp will flash
when the right combustion
section has an error code.
The mid red lamp will flash
when the left combustion
section has an error code.