Riello ER Series Installation, Use And Maintenance Instructions page 38

4.3 General gas supply layout (example)
D2604
Key to lay-out
AD2 Primary air damper
AD3 Secondary air damper
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
PGM Maximum gas pressure switch
PGm Minimum gas pressure switch
12
4
CHAPTER
RG Gas butterfly valve
SM1 Fuel servomotor
SM2 Primary air servomotor
SM3 Secondary air servomotor
SRV Pressure limiting valve with outlet into the environment
VA Air pressure regulation valve
VE Fan
VP Pilot solenoid valves
VPS Leak detection control device
VR Gas pressure regulator solenoid valve
VS Gas safety solenoid valve
LPRT Low pressure adjustment assembly
HPRT High pressure adjustment assembly
Burner supply
LPRT max. 500 mbar
HPRT 0.5 to 4 bar
Fig. 13