Error Priority - A.O. Smith 100 Series Installation And Operating Manual

ERROR PRIORITY

If multiple error conditions arise at the same time, the Control will
always give priority to hard faults over soft faults, and to soft faults
over warnings, in ascending "class" priority sequence.
In case of multiple errors of the same "class" (for example 2 or more
hard faults) at the same time, the Control uses the following priority
table (higher priority first).
Table 25. Error Priority
Hard Faults
ECO error, T > Tmax (201F)
Flue ECO Error, Tvent > Tvent max 165°F
Blower Speed error
Blower not running
Soft Faults
Blower Speed Error
Flame out of Sequence
Repeated Flame Loss
Ignition Failure
Blocked Flue 3rd
Blocked Flue, 1st, 2nd
Blocked air inlet, 1st, 2nd
Blocked air inlet 3rd
Auto reset / Warnings
NTC failure
Water Leak detected
LDM open
If there are multiple error conditions at the same time, and at least one
requires the buzzer, the buzzer will sound independent of the priority.
E00
E19
E21
E20
E21
E01
E02
E03
E05
E06
E22
E23
E07
E10
E11
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