Baxi Luna 3 Comfort Manual Para El Usuario Y El Instalador página 23

C) Pressure adjusting device setting (Figure 13)
• connect the positive pressure test point of a differential (possibly water-operated) manometer to the gas valve pressure
test point (Pb); connect, for sealed chamber models only, the negative pressure test point of the manometer to a "T"
fitting in order to join the boiler adjusting outlet, the gas valve adjusting outlet (Pc) and the manometer. (The same me-
asurement can be carried out by connecting the manometer to the pressure test point (Pb) after removing the sealed
chamber front panel);
If you measure the pressure of burners in a different way you may obtain an altered result in that the low pressure created
in the sealed chamber by the fan would not be taken into account.
SIT valve - mod. SIGMA 845
Figure 13
C1) Adjustment to nominal heat output
• open the gas tap;
• press button (figure 1) and set the boiler in winter mode;
• open a hot water tap to reach a minimum 10 l/min flow rate or ensure that maximum heating requirements are set;
• check that boiler feeding dynamic pressure, as measured at the inlet gas valve pressure test point (Pa) is correct (37
mbar for propane gas G.31, 20 mbar for natural gas G20);
• remove the modulator cover;
• adjust the tube brass screw (a) figure 14 to obtain the pressure settings shown in table 1;
C2) Adjustment to reduced heat output
• disconnect the modulator feeding cable and unscrew the (b) screw to reach the pressure setting corresponding to
reduced heat output (see table 1);
• connect the cable again;
• fit the modulator cover and seal.
C3) Final checks
• apply the additional dataplate, specifying the type of gas and settings applied.
INSTRUCTIONS PERTAINING TO THE INSTALLER
Honeywell valve - mod. VK 4105 M
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7864174 - en