A.O. Smith DRE PLUS Installation, User And Service Manual page 71

Code and description
045
(Blocking error)
Sensor error
Top sensor short
047
(Blocking error)
Sensor error
Top sensor open
0A5
(Lock out error)
Temperature error
Max. temperature excee-
ded (or thermal fuse acti-
vated)
4F1
(Blocking error)
Communication error
No communication be-
tween control board and
display board.
0313853_DRE PLUS_ENNLFR_V3.0, 20-06-2023
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.
Cause
Sensor is not (correctly) connected.
Damaged wiring and/or defective sensor. Replace the wiring and/or the sensor.
Short circuit in the sensor circuit.
The main safety thermostat (G1) is acti-
vated.
The thermal fuse broke the control cir-
cuit.
Wiring is damaged.
Measure
- Make sure that the connector is con-
nected to J5 Pin 2 and 3.
- Make sure that the wire is connected
to the sensor.
Replace the wiring and/or the sensor.
- 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.
- 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.
- 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.
EN
69