A.O. Smith DRE PLUS, Installation, User And Service Manual

Page: 71 / 242

Note
Contact your service and maintenance engineer if the error persists.
Note
Each error has a code and a description. The code has 7 characters: XXX-XXXX. When
the water heater has an error, the two digits before the dash (XXX-XXXX) are important
to pinpoint the error.
Code and description Cause Measure
045
(Blocking error)
Sensor error
Top sensor short
Sensor is not (correctly) connected. - Make sure that the connector is con-
nected to J5 Pin 2 and 3.
- Make sure that the wire is connected
to the sensor.
Damaged wiring and/or defective sensor. Replace the wiring and/or the sensor.
047
(Blocking error)
Sensor error
Top sensor open
Short circuit in the sensor circuit. Replace the wiring and/or the sensor.
0A5
(Lock out error)
Temperature error
Max. temperature excee-
ded (or thermal fuse acti-
vated)
The main safety thermostat (G1) is acti-
vated. - Make sure the water heater is com-
pletely filled.
- Tap off water, so the temperature
drops in the water heater.
- Make sure all connections are connec-
ted correctly, refer to the electrical
wiring diagram (see A.5).
- Use the white button to manually re-
set the thermostat.
- If necessary, replace the safety ther-
mostat (G1).
- Cycle power to the water heater to re-
set the error.
The thermal fuse broke the control cir-
cuit. - Check what caused the excessive heat
rise of the element area.
- Measure the resistance value over the
thermal fuse. The value needs to be
<5 Ohm.
- If necessary, replace the thermal fuse
wiring.
- Cycle power to the water heater to re-
set the error.
4F1
(Blocking error)
Communication error
No communication be-
tween control board and
display board.
Wiring is damaged. - Make sure that the wiring, between
the control board and the display
board, is connected and not damaged.
- If necessary, reconnect or replace the
wiring.
0313853_DRE PLUS_ENNLFR_V3.0, 20-06-2023 69
EN