A.O. Smith HYB-90N, Installation And Operating Manual

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42 www.hotwater.com 316888-001 Rev. 00 dRaFt Jun 28 245
If an error code is displayed, or odd behavior of the unit occurs, the fi rst corrective action should be to “Cycle the Power”:
Unplug the 120Vac power cord and after 5 seconds plug it in again. If this doesn’t clear the fault, proceed with the
“Remedy” in the following table (Table 5).
If wire harness checking is required, examine the integrity of wires themselves, the connector housings, the integrity of
the terminals as well as condition of the crimps.
Fault
Code
Displayed
Description Cause
Lockout
type
Remedy
E01, E02
Invalid Rated
KBtu/Model Type.
Control detects that the
con
fi guration selected is not
de fi ned or the con fi guration
has never been set.
Continuous
Change the main controller board
(board).
E03, E04,
E05, E06
Main Valve Relay
Out Of Sequence.
Control detects that a relay
used to enable the Main
Valve has failed in either the
open or closed position.
Soft Change the board.
E07 Flame Detected. Flame detected when no
fl ame was expected. Soft
Check the fl ame rod.
Check the fl ame wire harness.
Change the board.
1.
2.
3.
E08 ECO switch is
open. Control detects that the
ECO switch is open,
preventing power to the
Main Valve.
Continuous
Measure the water temperature.
ECO switch open temperature
is 85±5ºC (185±14ºF) and close
temperature is 65±5ºC (149±14ºF).
Check the ECO switch.
Check the ECO wire harness.
Change the board. 1.
2.
3.
4.
E09 High temperature
Vent Switch Open. Control detects that the High
Temperature Vent Switch is
open, preventing power to
the Main Valve.
Continuous
Measure the water temperature.
High Vent Switch open temperature
is 74±2.8ºC (165±5ºF) and close
temperature is 57±2.8ºC (135±5ºF).
Check the switch.
Check the High Vent Switch wire
harness.
Change the board. 1.
2.
3.
4.
E10 120Vac too high. 120Vac > Overvoltage Limit.
Auto Reset
Nominal voltage is 120Vac.
Overvoltage limit is 132Vac,
Undervoltage limit is 102Vac.
Check the power cord.
Check the wall outlet.
Measure the voltage at the board
connector J7 between pin1 and pin
3. If the voltage is between limits,
change the board. 1.
2.
3.
E11 120Vac too low. 120Vac < Undervoltage
Limit.
E12
Blower Current
abnormal.
Blower Current meets
requirements for a
completely blocked
fl ue.
Soft
Check the venting system. If the
venting system is clear, recalibrate
the unit.
Check the blower wire harness.
Change the blower.
Change the board. 1.
2.
3.
4.
E13 Blower Current meets
requirements for a partially
blocked
fl ue.
E14 Blower Current meets
requirements for a non-
heating blocked
fl ue
evaluation.
TABLE 5