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

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To switch the heater to OFF mode:
1.
Open the external enable inputs 1 and 2 (see 8.5).
3.2.1.2 ON mode
In the ON mode the water heater continuously responds to the heat demand. The electric
heating elements are activated when there is a heat demand.
Note
The ON mode is the factory default operating mode when the external enable 1 and 2
inputs are not used (both inputs are shorted from factory). This means the heating
elements are activated when the mains power is connected to the water heater.
3.2.1.3 Economy mode
In the Economy mode the water heater continuously responds to the heat demand based
on a reduced setpoint called Economy setpoint. The economy setpoint is determined by
the ON mode setpoint (see 4.1.1) minus the setpoint adjustment (see 9.4).
The Economy mode can be activated in two ways:
•
Using the week program in the Economy mode menu (see 9.4). This is only if the
external enable inputs 1 and 2 (see 8.5) are set correctly.
• Using the external enable inputs 1 and 2 (see 8.5) directly. Contact your service and
maintenance engineer if you want to use this functionality.
3.2.2 Error conditions
If there is an error or warning, the screen blinks and it shows a small description of the
error or warning.
Press [BACK] to return to the Home screen. The Home screen shows the exclamation
mark, or a question mark for a warning. For errors, the status changes to Error.
Fig. Error status
When the display shows an error:
1.
Switch the isolator between the water heater and the mains power supply off and on
to reset the water heater.
Note
Contact your service and maintenance engineer or supplier when the water heater does
not restart or when the display shows the error again.
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