Electrical Connections - SIT Group 822 NOVA Manual Del Usuario

MECHANICAL CONNECTIONS (fig. 1)
General recommendations:
Do not tamper with sealed parts. Do not slacken assembly screws. Do not remove labels. Avoid blows (knocks,
falls etc.). Only remove dust caps when installing. Do not exceed recommended torques. Ensure that the gas
flows in the direction shown by the arrow on the valve body.
Prevent foreign matter from getting into the valve during installation.
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 onto 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 SIT nut and olive or SIT pilot tube shear-
off connector. 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 combustion chamber (fig. 2)
A facility is provided for connecting the pressure regulator vent to the combustion chamber, if this is under
pressure. For this purpose the use of connection fittings 0.958.057 or 0.958.058 is recommended depending
on the features of the appliance. Fix the connection fitting to the bottom of the valve as shown in fig. 2.
Torque: 1 Nm.

ELECTRICAL CONNECTIONS

General precautions:
All electrical connections must be made in accordance with current electrical standards. Check that the
voltage and frequency of the coils, given on the valve, are correct. 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 special
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).
Make the connections using fast-on type 6.3 x 0.8 mm terminals. Make the connections as specified
in the technical instructions for the flame failure device used and/or in the specific standards for the appliance.
The electrical safety cut-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 (fig. 3)
All adjustments must be made on the basis of the specific characteristics of the appliance.
Check inlet and outlet pressure using the pressure test points provided. After testing, carefully seal test points
with the screws provided. Recommended torque: 2.5 Nm.
Adjusting the outlet pressure
Remove the protective cap (A).
Turning the setting screw (B) clockwise increases the pressure.
After adjusting, fit the plug (A) back firmly.
Overriding the pressure regulator function
Replace plug (A), setting screw (B) and spring (C) with the accessory (D) code 0.907.037. Torque: 1 Nm.
Adjustment of gas flow to the pilot burner (applications with pilot burner)
Turn the PILOT screw clockwise to reduce flow.
Overriding the pilot flow adjustment function
Screw the PILOT setting screw fully in and then unscrew it two turns.
Seal the adjustment.
Changing the gas family or group
Check that the appliance is suitable for operation with the gas family or group desired.
Following the instructions given above, adjust the outlet pressure to the values given in the instruction booklet of the
appliance. With Family 3 gas: override the pressure regulator and the gas flow regulator to the pilot burner.
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