Fuel Gas Firing – Piping Considerations
Fuel gas is usually dirty and frequently contains condensate.
To minimize plugging, any device that has small gas passages should connect to the top of the fuel gas lines (e.g., burners, minimum-fire bypass valves, and pressure control taps).
At the same time, the fuel gas lines should be sloped for complete draining and removing of condensate upstream of the firing control valve for each firebox. Downstream of the firing control valve, the gas velocity should sweep any remaining condensate along.
A block valve and blind is needed at each burner and on the gas line at least 100 feet from the firebox.