STIEBEL ELTRON LWZ 404 SOL Installation Manual

30 | LWZ304-404 SOL www.stiebel-eltron.com
INSTALLATION
Settings
 BOOSTER TIMEOUT
Direct line: P79
After starting the heat pump when heat demand is below the dual
mode point, the electric emergency/booster heater is blocked for
the time set under "BOOSTER TIMEOUT". This prevents the electric
emergency/booster heater switching on unnecessarily.
 OUTSIDE T CORRECTION
Direct line: P86
It may be advisable to correct the actual temperature value, be-
cause of tolerances of the outside temperature sensor and to com-
pensate for external influences, for example having the sensor in
an unfavourable position.
In parameter "OUTSIDE T CORRECTION", enter the difference be-
tween the actual outside temperature and the outside temperature
displayed on the programming unit.
Example:
Actual temperature 19 °C
Displayed temperature 21 °C
New parameter value -2
 SUPPR TEMP MEAS
Direct line: P58
After the heating circuit pump has started, the actual flow and
return temperatures remain suppressed for the time set under
the "SUPPR TEMP MEAS" parameter. The actual sensor values
are only used to calculate the heating system heat demand after
expiry of this time.
 HYSTERESES
 HYSTERESIS 1 P21
 HYSTERESIS 2 P22
 HYSTERESIS 3 P23
 HYSTERESIS 4 P24
 HYSTERESIS 5 P25
 ASYMMETRY OF HYST. P29
There are five parameters to define the start and stop hystereses
for heating mode. The switching hystereses are arranged sym-
metrically around the set heating circuit temperature.
If the heating circuit temperature drops, one output stage is start-
ed at "HYSTERESIS1".
At "Set heating circuit temperature - HYSTERESIS1 - HYSTERE-
SIS2", a further stage is started. If the heating circuit temperature
rises, one output stage is stopped at "Set heating circuit tempera-
ture + HYSTERESIS2". If the heating circuit temperature exceeds
"Set heating circuit temperature + HYSTERESIS1 + HYSTERESIS2",
a further output stage is stopped.
Usually, heating in a steady state switches back and forth between
two stages. Under certain conditions, large deviations from the set
value may occur if, for example, the heating circuit temperature
is far below the set value following a power-OFF period imple-
mented by the power supply utility, or if the set value changes
suddenly, such as after a setback time. Before the deviation from
the set value becomes too large, the heating stages are started or
stopped temporarily through the integral component.
Asymmetry of hystereses
If the heating temperature severely overshoots the set tempera-
ture, it may be necessary to reduce the hystereses above the set
value. The hystereses above the set value are divided by the value
set under the "ASYMMETRY OF HYST." parameter . If, for example,
a value of 2 is entered and "HYSTERESIS1" is 6K, then the heat
pump starts 6K below the set temperature and stops 3K above
the set temperature.
 DHW
 STANDARD SETTING
 HYSTERESIS
Direct line: P32
This determines the switching hysteresis for DHW operation.
DHW heating starts when the temperature falls below the set
DHW temperature minus "HYSTERESIS" . DHW heating stops
when the set DHW set temperature plus "HYSTERESIS" has been
reached.
 BOOSTER TIMEOUT
Direct line: P33
DHW is generally heated by heat pump (compressor mode). The
electric emergency/booster heater is switched on only if the re-
quired DHW temperature in the cylinder has not been reached
after "BOOSTER TIMEOUT" has expired.
Heating by the solar thermal system takes priority over the heat
pump if a solar thermal system is connected and there is adequate
insolation. This, on the other hand, takes priority over the electric
emergency/booster heater.
 BOOSTER T ACTIVATE
Direct line: P34
The electric emergency/booster heater for DHW heating is imme-
diately switched on if the outside temperature falls below the value
selected under the "BOOSTER T ACTIVATE" parameter. This means
heating is not interrupted for longer than necessary.
If the outside temperature lies above the value set in the "BOOST-
ER T ACTIVATE" parameter , then the electric emergency/booster
heater will only start after expiry of the "BOOSTER TIMEOUT", but
no sooner than after 10 minutes.
 PASTEURISATION
Direct line: P35
When starting the appliance, the water in the DHW cylinder is
heated up to the temperature set for pasteurisation. Subsequently,
the cylinder is heated up for pasteurisation according to the inter-
val (specified in days) set under the "PASTEURISATION" parameter
. The start point for the next interval occurs only when the tem-
perature set in the "PASTEURISATION TEMP." parameter has been
reached. This interval applies only if the DHW temperature has not
in the meantime exceeded the temperature set in the "PASTEURI-
SATION TEMP." parameter on account of other appliance functions.

STIEBEL ELTRON LWZ 404 SOL Specifications

General

Brand	STIEBEL ELTRON
Model	LWZ 404 SOL
Category	Fan
Language	English