SIT 828 NOVAMIX Bedienungsanleitung Seite 9

In particular, check the cleanliness of the inlet and outlet pipes. Do not subject the valve to bending in excess of 35 Nm
and to torque in excess of 25 Nm. Use only the specified spanner grips when making the connections.
Main gas connection
The connection must be made using gas pipes with Rp 1/2 ISO 7 thread.
Torque: 25 Nm. If, alternatively, flanges (available on request) are used, first screw the pipes on to the flanges and then
the flanges to the valve. Recommended torque or flange retaining screws: 3 Nm.
Connection to the pilot burner:
Ø4 mm, Ø 6 mm or Ø 1/4" pipes can be used. Use appropriately sized nut and olive. Tighten to 7 Nm torque.
CAUTION: If the pilot outlet is not used it must be sealed using plug code no. 0.972.041. Torque: 7 Nm.
Connection to the pneumatic control signals
This must be carried out so that danger conditions cannot be generated due to demand for gas in the absence of air flow.
Metal pipes of ø 4 mm, ø 6 mm or 1/4" are exclusively recommended. Use appropriate size of nut - and olive. Thighten
nuts with 7 Nm Torque.
CAUTION: On completing all mechanical connections, check for gas leakage.
ELECTRICAL CONNECTIONS
General precautions
All electrical connections must be made in accordance with current electrical standards.
Check that the supply voltage and frequency conform with those specified on the valve label. Check that all
connections, in particular the earth, are made properly. With the versions powered by mains voltage, the electrical
connections must be made using suitable connectors. In particular, to ensure that the valve is always connected to the
earth circuit of the appliance, it is necessary for the EV2 power connector, which includes the earth terminal,
to be used at all times and the screws protected against slackening.
The 24 Vac versions must be powered by an insulating transformer (at very low safety voltage in accordance with EN
60742). To connect these versions, use terminals AMP 6.3x0.8 DIN 46244 as an alternative to the connectors. Make
the connections as specified in the technical instructions of the flame failure device used and/or in the specific
standards for the appliance. The electrical safety shut-off devices (for example, the flame failure device, the thermostat
and so on) must cut off the power supply to both solenoid valves simultaneously.
SETTINGS AND ADJUSTMENTS
All adjustments must be made on the basis of the specific characteristics of the appliance, and only after having
installed the valve on the appliance. Check inlet, outlet gas pressure and air pressure using the pressure test points
provided E, A and G. After testing, carefully seal test points with the provided screws. Recommended torque: 2.5 Nm.
All adjustments must be carried out in the following order.
Version with ratio adjuster.
A
Adjustment of minimum outlet pressure Pu (min).
In absense of pneumatic control signal
(∆p (air) = 0 to iniets F) turn screw N.
Clockwise rotation:
pressure Pu (min) increases.
B
Adjustment of offset value.
With pneumatic control signal
at ∆p (air) at minimum value
(fan working at minimum speed),
turn adjusting screw Q so that
effective value coincides with
required theoretical value.
Clockwise rotation: characteristic
shifts to the left.
Pu
Pu
(air)
∆p
(air)
∆p
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