Riello DB 9 SE C03 FGR FS1 FB A0 Installation, Use And Maintenance Instructions page 32

4.2 General gas supply layout (example)
Fig. 14
D7543
Legenda
BP Pilot burner
C Anti-vibration joint
GF Gas filter
HPG High gas pressure regulator
LPG Low gas pressure regulator
MM Pressure gauge
PA Minimum air pressure switch
PCV Gas pressure regulator
12
4
CHAPTER Fuel supply
PGM Maximum gas pressure switch
PGm Minimum gas pressure switch
RG Gas butterfly valve
SRV Pressure limiting valve with outlet into the environment
VE Fan
VP Pilot solenoid valves
VPS Leak detection control device
VR Gas pressure regulator solenoid valve
VS Gas safety solenoid valve
max. 500 mbar
0,5 ÷ 4 bar