10
ENGLISH
VALLOX ROOF FANS
MAINTENANCE
The ball bearings of the roof fan motors are maintenance-free and have permanent lubrication that lasts for their entire lifespan.
Vallox roof fans must be serviced and cleaned from any dirt accumulated during use based on need.
Before maintenance measures the roof fan must be disconnected from the mains and accidental start-up must be prevented.
Roof fan models equipped with a
service switch (ECH)
Roof fan models that are equipped with a service switch are
delivered with a ready-connected potentiometer for adjusting
the fan speed. The control allows for selecting the desired
extraction air flow of the roof fan. In this case, the roof fan
only requires power supply to the service switch in order to
operate. The potentiometer is located in the connection box
that is delivered with the service switch (see the illustration).
To use the roof fan through an external control panel, the
wiring of the potentiometer must be disconnected (see the
schematic diagrams).
A
B
Adjusting the extraction air volume using the
service switch potentiometer
Open the cover (A) of the
connection box. Adjust the
desired air flow using the
potentiometer (B) (increase
the air flow by turning it to the
right and reduce the airflow
by turning it to the left). Close
the cover once you have set
the desired value.
Example of a service switch
installation
SERVICE SWITCH
Roof fan models without a service
switch
If the roof fan is not located in the same room space as the
group centre that feeds it, a safety switch must be installed in
the main circuit in its immediate vicinity.
If the temperature of the air to be extracted deviates from
+20 °C, the air flow can be calculated using the following
formula:
Roof fans 25P-EC...56P-EC are equipped with measuring
tubes. The pressure difference Δpm (Pa) measured from
them can together with the fan-specific k factor be used to
determine the air flow qv (dm³/s) of the roof fan.
Measuring tubes are located on the external envelope of the
roof fan and a manometer can be connected to them. The
measuring tube on the left is the + connector and the one on
the right is the – connector.
The k factors specified in the table apply to air density 1.2 kg/
m³ (+20 °C). The air flow can be calculated using the following
formula:
air density in the temperature
of the air that is to be
extracted
Roof fan
k factor
(
r
= 1,2 kg/m³)
25P-EC, 25P-ECH
16.1
31P-EC, 31P-ECH
31.1
40P-EC, 40P-ECH
50.0
50P-EC, 50P-ECH
80.8
56P-EC, 56P-ECH
100.0
r
20
= 1.2 kg/m³,
r
op
=
qv(dm
3
/s) = k *
√
∆pm
√
r
20
r
op
qv(dm
3
/s)
=
*
k
*
√
∆pm
AIR FLOW MEASUREMENT
Pivot point
