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www.stiebel-eltron.com
LWZ 304-404 SOL |
5
INSTALLATION
Appliance description
ed to the extract air system, you must also allow for a supply air
valve in the installation room in this particular case to prevent any
further increase in the negative pressure in the installation room.
The negative pressure created by the appliance in the installation
room is heavily influenced by the pressure drop in the outdoor
air line. For this reason, the outdoor air line in particular should
be as short as possible.
Note
The maximum permissible pressure drop (see chapter
"Specification / Data table / Max. pressure drop, outdoor
air") must not be exceeded.
3. Appliance description
The appliance comprises a function module and a cylinder module
that are supplied as separate shipping units. The wider module
with the air hose connections in the cover is the function module.
The components required for installation are in a separate carton
inside the function module packaging.
3.1 Standard delivery
!
Material losses
Never install the push-fit connectors in the DHW line.
Never install the push-fit connectors to the solar flow or
solar return connections. Only install the push-fit con-
nectors in the heating circuit.
The following are delivered with the appliance:
- Operating instructions
- Installation instructions
- Transport aid, comprising two angled brackets with screws
for fixing to the appliance
- Programming unit
- Outside temperature sensor
- Four adjustable feet for the cylinder module
- Eight sliding blocks for easier positioning of the appliance
- Hose clips to secure the air hoses
- Adhesive tape to seal the inner hose to the hose connector
- PE plate for connection to a geothermal heat exchanger or an
external fresh air intake
- Fixing materials (screws, washers, etc.)
- Three straight push-fit connectors for the hydraulic connec-
tion of the function and cylinder modules
For connection to the heating circuit:
- Two straight push-fit connectors
- One filter ball valve
- One ball valve
- Two 90° push-fit connectors
- Four straight pieces of pipe with G1 union nut
3.2 Required accessories
- Air hose with thermal insulation, 4 m
- Thermally insulated wall outlet with external wall grille
3.3 Further accessories
- Additional programming unit with wall mounted casing
- Spare filter set
- Diverter hood (enables the appliance to be sited in rooms
with ≥ 2.20 m head height)
- Silencer DN 315
- Relay set WPM-RBS
- Segmented anode
- Starting current limiter 25 A (part number 281546)
- DHW circulation pipe set
- Filter box (for installation in round DN 160 ventilation pipes)
- PK10 condensate pump
- Safety temperature controller for underfloor heating system
3.4 Appliance functions
The supply air fan induces outdoor air into the appliance. The
extract air fan draws stale air from the living areas into the appli-
ance. Outdoor air and extract air are routed through particle air
filters into separate ducts of a cross-countercurrent heat exchang-
er. Inside the cross-countercurrent heat exchanger, the outdoor
air is heated and channelled into the living space as supply air.
The extract air cools down inside the cross-countercurrent heat
exchanger and is routed as exhaust air first through the evaporator
and then outdoors.
The cross-countercurrent heat exchanger ensures that up to 90 %
of the heat in the extract air is returned with the supply air into
the living space.
In addition, heat is extracted from the outdoor air by means of an
air source heat pump. The energy extracted from the outdoor air
in the evaporator is transferred via the condenser to the central
heating or DHW system.
In the case of low outside temperatures or high heat demand
from the central heating or DHW heating systems, the additional
heat demand is covered by an electric emergency/booster heater.
3.4.1 Utilising solar energy
A solar heat exchanger is integrated into the appliance. You can
connect a solar thermal system to this coil by means of the appli-
ance solar flow and solar return connections. Solar backup can
be provided both in central heating mode and DHW mode. A dif-
ferential temperature controller for the solar thermal system is
integrated in the appliance control unit.
!
Material losses
In some operating situations, the solar circuit pump will
be operated cyclically. HE pumps should not be used.
Otherwise the appliance or the solar circuit pump may
be damaged.
