A.O. Smith HW 610 - Manual (Page 52)

52
The following procedures are provided as a general guide.
Any module should be replaced if it does not perform properly on
checkout or troubleshooting.
In addition, replace any module if it is wet or looks like it has ever
been wet.
LED STATUS AND TROUBLESHOOTING
The control has two LEDs; one for flame sensing and one for
system status:
FIGURE 37.
Location of LEDs.
• Flame LED (Yellow)
– Indicates flame presence and strength. See Table 11.
• Status LED (Green)
– Indicates system operation status and error conditions. See
Table 12 and Table 13 on pages 53 and 54 for status specific
to each model.
Table 11
Yellow LED Flame Codes
Yellow LED
Flash Code a
Indicates
Recommended
Service Action
Heartbeat Normal Flame Signal not applicable
2
Weak Flame Signal-
Sytem will operate
reliably but flame
signal is less than
desired.
NOTE: This indication
may flash temporarily
during or shortly
after lightoff on some
applications.
Perform routine
maintenance to
assure optimum
flame signal.
1
Marginal Flame Signal
(less than 1.1µA)-
System may not
operate reliably over
time.
Service call
recommended.
NOTE: This indication
may flash temporarily
during or shortly
after lightoff on some
applications.
Check gas supply,
pilot burner, flame
sense wiring,
contamination of
flame rod, burner
ground connection.
OFF
No Flame or Flame
Signal below minimum
threshold for system
operation.
not applicable
a Flash Code Descriptions:
- Heartbeat: Constant 1/2 second bright 1/2 second dim cycles.
- The flash code number signifies that the LED flashes X times
at 2Hz, remains off for two seconds, and then repeats the
sequence.