General Ventilation Connection; Ventilation Flow; Adjusting Ventilation - Nibe F470 Installer Manual

General ventilation
connection
• Ventilation installation must be carried out in accord-
ance with current norms and directives.
• Connections must be made via flexible hoses, which
should be installed so that they are easy to replace.
• Provision must be made for inspection and cleaning
of the duct.
• Make sure that there are no reductions of cross-sec-
tional area in the form of creases, tight bends, etc.,
since this will reduce the ventilation capacity.
• The air duct system must be a minimum of air tight-
ness class B.
• To prevent fan noise being transferred to the ventila-
tion devices, install silencers in the ducts.
• The extract air and outdoor air ducts are insulated us-
ing diffusion-proof material (at least PE30 or equival-
ent) along their entire lengths.
• Ensure that the condensation insulation is fully sealed
at any joints and/or at lead-in nipples, silencers, roof
cowls or similar.
• The air must be routed to the outdoor air duct through
an outer wall grille in the facade. The outer wall grille
must be installed so that it is protected from the
weather and must be designed so that no rainwater
and/or snow can penetrate the facade or follow the
air into the duct.
• When positioning the outdoor air and extract air
hood/grille, bear in mind that the two air flows must
not short circuit to prevent the extract air from being
drawn into F470 again.
• The extract air duct must be a maximum of 20 m long
with a maximum of six bends.
• Because the heat pump contains the flammable refri-
gerant propane (R290), the air ducting system must
be earthed. This is achieved by making a good electric-
al connection to the four ventilation ducts using the
enclosed earth cables (4 pcs). The cables must then
be connected to the earth pins on top of the top cover.
• A duct in a masonry chimney stack must not be used
for extract air or outdoor air.
• When external devices that affect the ventilation are
used, for example kitchen fans and stoves, the heat
pump must be in operation. There is a risk of freezing
at low outdoor temperatures.
NIBE F470
NOTE
External frost protection must be installed in
the outdoor air duct.
• The frost protection must be dimensioned to seal
against the underpressure that can be created in the
house when a fire is lit in the stove when the supply
air fan and heat pump are switched off. An external
supply air duct for the stove is recommended.
EXHAUST AIR DUCT /KITCHEN FAN
Exhaust air duct (kitchen fan) must not be connected to
F470.
To prevent food vapour being transferred to F470 the
distance between the kitchen fan and the exhaust air
device must be considered. The distance should not be
less than 1.5 m, but this can vary between different in-
stallations.
Always use a kitchen fan when cooking.

Ventilation flow

Connect F470 so that all the exhaust air, except kitchen
duct air (kitchen fan), passes through the evaporator
(EP1) in the heat pump.
The ventilation flow must comply with the applicable
national standards.
For optimum heat pump performance, the ventilation
flow must not be less than 28 l/s (100 m³/h) at an ex-
haust air temperature of at least 20°C. When the exhaust
air temperature is lower than 20°C (for example at start-
up and when there is nobody at home), the minimum
value is 31 l/s (110 m³/h).
The supply air flow must be lower than the exhaust air
flow to prevent over pressure in the house.
The heat pump's installation area must be ventilated to
at least 5 l/s (18 m³/h)
Set the ventilation capacity in the heat pump's menu
system (menu 5.1.5).
If the exhaust air temperature falls below 16°C, the
compressor is blocked and electric additional heat is
permitted. No energy is recovered from the exhaust air
when the compressor is blocked.

Adjusting ventilation

To obtain the necessary air exchange in every room of
the house, the exhaust air device and the supply air
device must be correctly positioned and adjusted and
the fans in the heat pump adjusted.
Chapter 4 | Pipe and ventilation connections 21