4.5.1 Adjusting Gas Pressure - Beretta Novella MAXIMA 129 N RAI Installation Manual

4.5.1 Adjusting gas pressure

Pressures have to be adjusted in a specific
order. Always adjust maximum pressure first
and then minimum pressure (Fig. 4.17):
Adjusting maximum pressure
Proceed as follows to adjust maximum pres-
sure.
- Connect a column or dial type pressure
gauge to the pressure measurement point
on the burner manifold.
- Unscrew the plastic cap from the pressure
regulator.
- Turn the boiler control thermostat to its max-
imum value.
- Start up the boiler.
- Turn the adjuster screw (8, Fig. 4.17)
anti-clockwise to reduce pressure, clock-
wise to increase it.
- Turn the boiler off and on a number of times
at the main power switch and check that
pressure remains as specified in the table.
- Seal the pressure adjuster screw (8) and
replace the plastic cap.
Adjusting minimum pressure
Once you have adjusted maximum pressure,
proceed as follows to adjust minimum pres-
32
sure.
- Use the same column or dial type pressure
gauge to measure pressure.
- Start up the boiler and leave it run at its
rated power for a while, then slowly turn
the boiler control thermostat towards its
minimum setting until you hear a click from
the thermostat.
- Leave the thermostat knob in that position.
Unscrew the plug and turn the screw (9,
Fig. 4.17) to establish the minimum pres-
sure value specified in the table for the type
of gas supply. Turn the adjuster screw (9)
clockwise to reduce pressure, anti-clock-
wise to increase it.
NOVELLA MAXIMA
Butane (G30)
Max. burner pressure mbar
Min. burner pressure mbar
Propane (G31)
Max. burner pressure mbar
Min. burner pressure mbar
129-151-172-194-215-237-258-279 N RAI
28
15
35
15
8
9
Fig. 4.17
Fig. 4.18