A.O. Smith CAWH 8-455-12, Installation, User And Service Manual

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3.2.1 Operating modes
The CAWH has 3 operating modes:
• Efficiency mode (see 3.2.1.1)
• Hybrid mode (see 3.2.1.2)
• Electric mode (see 3.2.1.3)
3.2.1.1 Efficiency mode
Efficiency mode is the default, recommended setting. The Efficiency mode is the most
energy efficient mode. This mode predominantly uses the heat pump to heat water in the
tank. In case of low demand, the upper heating element is not used and the lower heating
element will only be used in case the ambient temperature drops below 7°C. For high
demand, an anti-cold-water function controls the upper and lower element, but only in
case the ambient air temperature is insufficient for recovery. If hot water demands are not
met in Efficiency mode, it may be necessary to switch to Hybrid mode.
3.2.1.2 Hybrid mode
Hybrid mode combines high energy efficiency with reduced recovery time. This mode uses
the heat pump as the primary heating source. The heating elements will heat water if
demand exceeds a predetermined level so that the setpoint temperature can be recovered
more quickly
3.2.1.3 Electric mode
In the Electric mode the water heater functions as a conventional electric unit, relying
totally on the heating elements to heat the water in the tank. This mode may be useful in
winter to eliminate the output of cold air from the unit.
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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22 User part
EN