Instructions Unit installation
2.4 Balancing of
the main air volumes
9
VIEWA402
Why should you balance the system?
To achieve the best possible performance, it is
vital to balance the main air volumes. A balance
should be found between the main air volumes
in the house (this will contribute to protecting
the house against fungus and dry rot).
Setting up with low outdoor temperatures
If the outdoor temperature is below -3°C, the
system should not be balanced/commisioned as
the system will go into frost protection mode. A
flashing icon will show this on the display.
Note! If forced to balance a unit at outdoor air
temperatures below -3°C, remove power from
the ventilation unit for 20 seconds. The system can
then be balanced for up to 1½ hours, after which
the frost protection mode will again become
active (if conditions apply).
How to balance the main air volume -
Danfoss supplied the complete duct system
1. Remove front panel from unit (you do not need
tools, simply pull lightly at handles).
2. See the drawing of the duct system included.
Here you will find suggested pre-setting values
for all air valves. Close valves completely, and
turn them full turns towards ”open” (number of
turns as indicated on the duct system drawing).
If dampers are included in the system, open
these completely before set-up is commenced.
3. Mount measuring tubes between the unit’s
measuring spigots on the exhaust side (see
illustration above) and differential pressure
gauge.
4. Find the required flow on the system diagram
(blue sticker) with the corresponding differential
pressure value. This is the pressure the measur-
ing equipment must show to ensure that the
flow is = as required. If the pressure is too low,
adjust the fan step upwards until you reach the
required pressure. Now move the measuring
tubes over onto the opposite measuring points
and use the same procedure to set up the sup-
ply air. All that remains is a quick fine-tuning
of the room air volumes as the presettings
are usually close to the required flow. See also
page 20 for further details about set-up.
Setting up a system that is operational, but
has not yet been adjusted
Press Air Dial for 5 seconds. The hidden Service
menu appears. In the Service menu, press ”set
basic step” to activate the special commissioning
mode (where all outside influences are blocked
– the installer controls the exhaust and supply
air fans completely with 1-100% fan speed). The
Service menu remains visible for one hour and
then disappears.
How to balance the main air volume in a duct
system provided by a different supplier:
1. Remove front panel from unit (you do not need
tools - simply pull firmly on handles). When
setting up systems for which Danfoss has not
dimensioned the duct system, set the supply
and exhaust valves in accordance with the
instructions of the project manager.
2. Mount measuring tubes between the unit’s
measuring spigots on the exhaust side (see illus-
tration above) and differential pressure gauge.
3. Find the required flow on the system diagram
(blue sticker) with the corresponding differ-
ential pressure value. This is the pressure the
measuring equipment must show to ensure
that the flow is = as required. If the pressure is
too low, adjust the fan step upwards until you
reach the required pressure. Now move the
measuring tubes over onto the opposite meas-
uring points and use the same procedure to set
up the supply air. All that remains is to set up
the room air volumes.
After the main air volumes have been adjusted, the
set-up of individual valves needs to be carried out.
In most cases, this will entail minor changes to the
chosen basic steps, but this can be done in the room
by adjusting the valves.
How to measure
supply
How to measure
exhaust