Instructions / Assembly
OPERATION
Settings
www.stiebel-eltron-usa.com Accelera® 220-300 E | 15
ENGLISH
Operation with external signal transmitter (240 V input)
The connection of the heat pump to an external signal offers the
possibility of heating water to a raised temperature set point
during periods when electric rates are favorable, for example
during times when PV power is available or low tariff utility rates
are in effect.
The external signal may be offered by a PV system or off-peak
electricity rates of a utility.
If an external signal is received, set temperature 2 becomes active,
overriding set temperature 1, the standard set DHW temperature.
If set temperature 2 has been activated by the external signal
transmitter, this set temperature will then be active for at least
20 minutes. If the signal remains active after those 20 minutes
passed, the compressor will run until the external signal. If not,
the selected set temperature 1 is activated again.
If the relevant set DHW temperature is accomplished, the com-
pressor switches off and remains off for a minimum idle time of
20minutes.
The following diagram illustrates the connections by means of a
sample signal sequence of an external signal transmitter.
Example:
- DHW temperature = 131 °F (55 °C)
- Set temperature 1 = 124 °F (50 °C)
- Set temperature 2 = 149 °F (65 °C)
A
240 V
0 V
0 5 1015202530354045505560657075t [min]
B
On
1
Off 2
0 5 1015202530354045505560657075t [min]
D0000034613
A LF signal
B Compressor
1 20 min. minimum runtime, set temperature 2
2 20 min. minimum compressor idle time
Note
An LF signal must be active for at least 60seconds 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.
5.2.7 Reload factor
Reload factor determines the percentage of energy content in the
tank required to turn on the heat pump. 40% means that the heat
pump will activate when 40% of tank contents remain. This may
be adjusted to a maximum of 60%.
Factory setting
Reload factor % 40
Press the "Menu" key, until an "L" fol-
lowed by a number appears in the dis-
play.
You can change the value using the "Plus"
and "Minus" keys. Setting range: 30–60%
5.2.8 Fault code
If the "Service/fault" symbol illuminates
or flashes, you can query the fault code
using the "Menu" key. This menu remains
disabled if no fault has arisen.
See 7.1, “Fault codes”, pg. 18
5.2.9 E fault code
A fault code preceded by E appears if the fault relates to the re-
frigerant circuit. Notify a qualified contractor.
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 temperature1”, pg. 14), or Set
temperature 2 (See 5.2.5, “Set temperature2”, pg. 14) 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