VALLOX 90K SC
INSTRUCTIONS FOR USE
5
2.3. Heat recovery bypass
In winter use the heat recovery cell of VALLOX 90K SC recovers heat from the air leaving
the dwelling and uses it to heat the air coming from the outside.
In summer use when it is warm outside, it is unnecessary to heat outdoor air. The heat recovery
cell is bypassed in VALLOX 90K SC with the standard damper (A). The position of the damper
can be changed by opening the damper release (B) and then moving the summer/winter
damper in another position. In the summer position air flow through the cell is prevented,
and heat recovery bypass is activated.
2.4. Air filtering
VALLOX 90K SC features coarse filtering of both extract and supply air before the fans. The
supply air side includes a G3 class coarse filter (C) and the extract air side a G3 class coarse
filter (D). The unit can also be equipped with an F7 fine filter (E), which captures fine dust
and pollen as well dust not seen to the eye. The filters need to be in place in the unit whenever
ventilation is in operation.
2.5. Defrosting
Water condensing from extract air may freeze in the heat recovery cell. Freezing can be
prevented by stopping the supply air fan, or the unit can be equipped with an optional
preheating resistor, which is switched on as needed.
2.6. Stopping the supply air fan
Defrost thermostat T1 stops the supply air fan whenever the temperature of extract air goes
below +5
°
C after the cell. The fan restarts when temperature has risen by circa three degrees,
i.e. to +8
°
C. The limit of the thermostat (F) can be adjusted at the back of the heat recovery
cell. If the unit includes a preheating radiator (G), the supply air fan cannot be stopped.
2.7. Outdoor air preheating
The unit may have been equipped with a preheating radiator at the factory. If this is the case,
defrost thermostat T1 switches the preheating radiator on whenever the temperature of extract
air goes below +5
°
C after the cell. The preheating radiator switches off when temperature
has risen by circa three degrees, i.e. to +8
°
C. The preheating radiator heats outdoor air
before the cell and prevents it from freezing. In very cold temperatures the preheating radiator
is not enough to heat maximum air flow to a sufficient degree (in a temperature of -30
°
C,
maximum air flow is 30 dm
3
/s, which corresponds to speed 2). The limit of the thermostat
can be adjusted at the back of the heat recovery cell.
2.8. Post-heating
For most of the year, heat recovered from the air being extracted is enough to warm the cold
air coming from the outside to a suitable temperature. If the heat of extract air is not enough,
air coming from the outside may be heated further with a radiator installed outside of the
unit (for instance VALLOX 1000 supply air heater).
F
G
Preheating radiator (G)
Preheating radiator is lo-
cated behind a shield.
Summer/winter damper
in winter position
Summer/winter damper
in summer position.
You can switch the summer/winter damper to
winter position by pushing the damper behind
the holder.
A
B
C
D
E
G
Defrost thermostat (F)
First remove the heat recovery
cell, then the cap protecting the
adjusting screw of the thermostat.
F