Generac 04673-2 Fuel Requirements And Recommendations, Fuel Consumption, 3 - Demand Regulator

Section 1 — General Information

Generac Air-cooled 7 kW, 12 kW and 15 kW Generators

1.6FUEL REQUIREMENTS

AND RECOMMENDATIONS

With LP gas, use only the vapor withdrawal system. This type of system uses the vapors formed above the liquid fuel in the storage tank.

The engine has been fitted with a fuel carburetion system that meets the specifications of the 1997 California Air Resources Board for tamper-proof dual fuel systems. The unit will run on natural gas or LP gas, but it has been factory set to run on natural gas. Should the primary fuel need to be changed to LP gas, the fuel system needs to be reconfigured. See Section 1.9 for instructions on reconfiguration of the fuel system.

Recommended fuels should have a Btu content of at least 1,000 Btus per cubic foot for natural gas; or at least 2,520 Btus per cubic foot for LP gas. Ask the fuel supplier for the Btu content of the fuel.

Required fuel pressure for natural gas is 5 inches to 7 inches water colum (0.18 to 0.25 psi); and for

3.Remove the battery (if installed).

4.Disconnect wire #0 and wire #14 from the gas solenoid on top of the demand regulator.

5.Remove the carburetor fuel hose from the outlet port of the demand regulator.

6.Remove the demand regulator by removing the fastener that retains the regulator mounting bracket.

7.Remove the square headed steel pipe plug from outlet port #1 and the brass hose barb fitting from outlet port #2.

8.Refit the brass hose barb fitting to outlet port #1 and the square headed steel pipe plug to outlet port #2.

9.Reverse procedure steps 1-5 to reinstall demand regulator.

10.Reverse the procedure to convert back to natural gas.

Figure 1.3 – Demand Regulator

liquid propane, 11 inches to 14 inches of water column (0.4 to 0.5 psi).

NOTE:

Any piping used to connect the generator to the fuel supply should be of adequate size to ensure the fuel pressure NEVER drops below 4 inches water colum for natural gas or 10 inches water col- umn for liquid propane for all load ranges.

1.7FUEL CONSUMPTION

FUEL HOSE

BRASS HOSE FITTING

ADJUSTMENT SCREW

HOSE & PLUG

SWITCHED SIDES

PIPE	FUEL HOSE
PLUG

BRASS HOSE

FITTING

OUTLET

PORT

FUEL JET

Model #	Nat. Gas (*)		LP Vapor (**)
	1/2 Load	Full Load	1/2 Load	Full Load
04673	66	119	0.82/30	1.47/54
04674	152	215	1.53/56	2.08/76
04675	156	220	1.58/58	2.40/88

*Natural gas is in cubic feet per hour.

**LP is in gallons per hour/cubic feet per hour.

1.8RECONFIGURING THE FUEL SYSTEM

◆1.8.1 7 KW, 410CC

To reconfigure the fuel system from NG to LP, follow these steps (Figure 1.3):

NOTE:

The primary regulator for the propane supply is NOT INCLUDED with the generator. A fuel pres- sure of 11 to 14 inches of water column (0.4 to 0.5 psi) to the fuel inlet of the generator MUST BE SUPPLIED.

NG FUEL SYSTEM LP FUEL SYSTEM

NOTE:

The natural gas adjustment screw is preset during installation and should not need any further adjustment.

◆1.8.2 12KW AND 15KW, V-TWIN ENGINES

To reconfigure the fuel system from NG to LP, follow these steps:

NOTE:

The primary regulator for the propane supply is NOT INCLUDED with the generator. A fuel pres- sure of 11 to 14 inches of water column (0.4 to 0.5 psi) to the fuel inlet of the generator MUST BE SUPPLIED.

1.Turn off the gas supply. (if connected)

2.Open the roof and remove the door.

1.Turn off the main gas supply (if connected).

2.Open the roof and remove the door.

3. Remove the battery. (if installed)

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