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9
Vallox
90
K
MC
© VALLOX • We reserve the right to make changes without prior notice.
What the units include can vary depending on the sales area.
MC CONTROLLER
Indicator
Indicator (A) shown in Figure 1 is lit when the MC ventilation unit controlled by the hood is
on. If the indicator blinks at one-second intervals, the ventilation unit reminds of the need for
maintenance. The reminder is given at half-year intervals. The maintenance reminder is reset
when the cover of the ventilation unit is opened. The instructions for the ventilation unit also
include explanations for other cases where the indicator blinks in fault situations.
The indicator is not in use if a cooker hood is used to control roof fans or other ventilation unit
or the indicator is not connected to the ventilation unit.
Adjustment of fan speeds
A low signal voltage comes to the controller, which means that the adjustment can be made
when the controller is connected and the ventilation unit is in operation.
• The adjustment is conducted in the four holes below the controller knob (Figure 2) one
speed at a time, at the potentiometer corresponding to each speed.
• The voltage adjusted can be measured at the measuring points found below the knob
(markings S and –) or on the terminal block below a black housing (markings S and –,
see Figure 6) with a multimeter direct-current voltage measurement. The adjustment range
is ~2...11.2 V.
• Control voltage (air flow) rises when the potentiometer is turned clockwise. The preset
voltages are as follows: 2.5 V, 5 V, 7.5 V and 10 V.
Note! Do not set control voltage so low that the fan does not start (circa 1.5 V).
Sample adjustment of air flows:
Basic ventilation is adjusted at speed 2.
• Set the controller at speed 2 and measure air flows at the valves.
• If the total air flow is too low, set the control voltage higher at potentiometer 2.
• If the total air flow is too high, set the control voltage lower at potentiometer 2.
Do not throttle the air flow unnecessarily with valves.
• The balance between supply and extract air flows in the Vallox MC ventilation unit can
be adjusted with the potentiometer inside the unit. Do not change this balance during
measurements carried out at other speeds.
• Adjust the absence air flows correspondingly at speed 1 (potentiometer 1).
• Adjust the boosting air flows correspondingly at speed 3 (potentiometer 3).
• You can usually leave speed 4 for full power.
Finally, measure voltage at all speeds at the measurement pins and enter them in the
measurement record. In for instance a terraced house, you can use voltage measurement to
copy the measurement in the first dwelling to other similar dwellings.
Set the speed knob in position 1 and
detach the knob with for instance
screwdriver.
There are adjustment and measurement
holes between the knob.
Measure voltage at contacts – and S,
adjust for instance speed 1
at potentiometer 1.
Put the knob back in place, turn the knob to
the following speed position and detach the
knob again.
Measure voltage at contacts – and S, adjust
speed 2 at potentiometer 2,
and so on.
You can also carry out the measurement at
the terminal block, in locations shown in the
electrical diagram.