OPERATION
Settings
14
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Note
An LF signal must be active for at least 60 seconds before
the control unit responds to it. This prevents cycling of the
compressor due to fast changing sun radiation conditions.
5.2.6 Changing
units
This appliance is capable of displaying temperature and volume
in either US units or SI units. A selection of 0 at this screen will
show units in Fahrenheit and gallons. A selection of 1 screen will
show units in Celsius and liters.
Press the menu key until the screen dis-
plays “SI” and either 0 or 1.
Adjust the display units from US to SI (0
to 1) using the plus and minus keys.
5.3
Changing mode of operation
This appliance has two operating modes which determine the
relative use of the heat pump to the backup electric element:
Automatic Mode & Heat Pump Only Mode.
5.3.1
Automatic
Mode
The appliance ships factory set to Automatic Mode. In Automatic
Mode, water is heated primarily with the heat pump to satisfy Set
temperature 1 (See 5.2.3, “Set temperature 1”, pg. 13), or Set
temperature 2 (See 5.2.5, “Set temperature 2”, pg. 13) If the hot
water consumption is more than the heat pump can keep up by
itself, Automatic Mode automatically activates the backup element
to provide additional heating and faster hot water recovery.
Automatic Mode balances energy savings with user comfort by
relying primarily on the heat pump and automatically activating
the backup electric element during times of high hot water de-
mand. Automatic Mode is the recommended operation mode for
most installations.
5.3.2 Heat Pump Only Mode
During installation the appliance can be manually set to Heat
Pump Only Mode by a technician. In this mode, the backup ele-
ment is not activated during normal operation, and the heat pump
is the source of heating. If the tank contents become exhausted,
the user must either wait for the heat pump to reheat the tank or
press the rapid heating key for backup comfort heating (See 5.5.1,
“Comfort heating”, pg. 14).
Heat Pump Only Mode prioritizes energy savings over the hot
water recovery rate. Heat Pump Only Mode is recommended for
installations where curtailing energy usage is of the highest con-
cern, such as an installation where power is off-grid. Note that
even when Heat Pump Only Mode is selected that freeze protection
is still active (See 5.2.4, “Freeze protection”, pg. 13).
5.4
Calling up fault codes
While on the “changing units” menu,
press the menu key to get to the fault
code menu. A fault code will appear if
a fault has occurred. If no error has oc-
curred, this menu is not available.
See 7.1, “Fault codes”, pg. 17 .
5.5
Rapid heating key
Press the rapid heating key.
The electric booster element symbol ap-
pears. The heat pump symbol may ap-
pear depending on the tank temperature
when the button is pressed.
5.5.1
Comfort
heating
The rapid heating key activates the comfort heating function,
which enables the water heater to satisfy a high DHW demand
without changing any of the appliance’s standard settings.
When comfort heating is activated by pressing the rapid heating
key, the heat pump and the booster element will start in parallel,
irrespective of the current tank temperature. The heat pump and
booster will remain active until the tank temperature reaches the
set temperature.
In addition, the booster element will work in parallel with the heat
pump during normal operation for 48 hours. After 48 hours, the
appliance switches back to previously set parameters.
Note
The electric booster element and heat pump symbols are
displayed until the comfort heating function has ended.
During comfort heating, the electric element switches
off once the upper section of the tank is heated to the set
temperature. The heat pump switches off when the entire
tank is heated to the set temperature.
