Generac Power Systems 940-2 Fuel Supply Lines, Excess Flow Valve, A Typical LP Gas Fuel System

Section 4.1

INTRODUCTION TO FUEL SYSTEM

IMPORTANT CONSIDERATIONS (CONTINUED)

NOTE: A PRIMARY REGULATOR, between the tank and the fuel lockoff solenoid, is required to ensure that correct gas pressure is delivered to the lockoff solenoid.

•The generator installer's connection point is at the fuel lockoff solenoid which has a 3/4 inch (female) connection.

•A length of flexible hose is required between the fuel lockoff solenoid and rigid fuel piping, to allow for vibration and/or shifting of the unit. This line must be at least six (6) inches longer than neces- sary.

•Gaseous fuel lines and primary regulators must be properly sized to deliver adequate fuel flow to the generator engine. The generator requires at least 67 cubic feet of gas per hour for its operation.

NOTE: An existing primary regulator may be used to deliver gas to the fuel lockoff solenoid provid- ed It has sufficient flow capacity for the generator and other gas appliances in the circuit. If the existing primary regulator does not have a suffi- cient capacity (a) replace it with one that has ade- quate flow capacity, or (b) install a separate pri- mary regulator having at least a 67 cubic feet per hour capacity.

FUEL SUPPLY LINES

When servicing or repairing the gaseous fuel system, the following rules apply to gaseous fuel supply lines:

•The LP gas lines must be accessible but must also be protected against possible damage.

•Do NOT connect electrical wiring to any gaseous fuel line. Do NOT route electrical wiring alongside the gaseous fuel lines.

•Route the gaseous fuel lines AWAY from hot engine exhaust mufflers and piping.

•Gas lines should be retained with metal clamps that do not have any sharp edges.

EXCESS FLOW VALVE

Rules established by the National Fire Protection Association (NFPA) and the Recreation Vehicle Industry Association (RVIA) require that the LP gas tank be equipped with an excess flow valve. This valve and the gaseous fuel lines must be carefully sized so the excess flow valve will close in the event of line breakage.

Shutoff valves on the fuel supply tank and elsewhere in the system must be fully open when operating the generator. The excess flow valve will function proper- ly only if all valves are fully open and fuel lines are properly sized.

Figure 1. A Typical LP Gas Fuel System

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