Greenheck DGX Installation, Operation And Maintenance Manual page 46

Reference
Typical Gas Train Layout less than 400 MBH
Burner Differential
Pressure Sensor
(Airflow Switch)
To Burner
High Gas
Pressure Switch
Combination
Low Gas
(Optional)
Shut-off
Pressure Switch
Modulating
Valve/Regulator
(Optional)
Valve
Burner Manual
Shut-off Valve
Low Gas
Pressure Test
Port
High Gas
Pressure Test
Port
Gas
Connection
Figure 66. Direct Spark Gas Train
NOTE!
This is a typical gas train. The gas train in your unit may be different.
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