Reference; Typical Gas Train Layout - Greenheck VSU Installation, Operation And Maintenance Manual

Reference

Typical Gas Train Layout with Modulating Valve (Pilot Ignition)
Burner Differential
Pressure Sensor
Airflow
Burner Manual
Shut-Off Valve
High Gas Pressure
Switch (optional)
Burner Gas
Pressure Test Port
Typical Gas Train Layout with Modulating Regulator (Pilot Ignition)
Burner Differential
Pressure Sensor
Airflow
Burner Manual
Shut-Off Valve
High Gas Pressure
Switch (optional)
Burner Gas
Pressure Test Port
®
Pilot Gas Pressure
Test Port
Modulating
Valve
Safety Shut-Off Valves
Pilot Gas Pressure
Test Port
Modulating/Regulator
Valve
Safety Shut-Off Valves
Pilot Solenoid
Pilot Regulator
Low Gas Pressure
Switch (optional)
Regulator
Pilot Solenoid
Pilot Regulator
Low Gas Pressure
Switch (optional)
Model VSU Make-Up Air
Manual Pilot
Shut-Off Valve
Manual Pilot
Shut-Off Valve
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