System SET LED | Generac Power Systems 04389-2, 04456-2, 04390-2

Section 1 — General Information

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

1.6SYSTEM SET LED

The “System Set” LED is lit when all of the following conditions are true:

1.The AUTO/OFF/MANUAL switch is set to the AUTO position.

2.The utility voltage being supplied to the unit is being sensed by the PCB. If the utility sense volt- age is not connected to the unit or if it is below 168 volts AC, then the system set light will flash rapidly. This indicates that if the AUTO/OFF/ MANUAL switch is placed in the Auto position, the generator will start.

3.The “Not In Auto” dip switch is set to the OFF position on the control board.

4.No alarms are present, for example, low oil pres- sure, high temperature, etc.

1.7FUEL 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.

Fuel pressure for both natural gas and liquid propane set ups should be 11 inches to 14 inches of water column (0.4 to 0.5 psi) at all load ranges.

NOTE:

A separate gas line and regulator may be needed to assure proper gas pressure (11-14”) to the gen- erator. Low gas pressure can cause hard starting and could affect engine durability.

1.8FUEL CONSUMPTION

Model #	Nat. Gas (*)		LP Vapor (**)
	1/2 Load	Full Load	1/2 Load	Full Load
04389	74	105	0.91/33	1.21/44.1
04456	114	185	1.34/48.9	2.17/79.0
04390	148.5	240	1.73/63.2	2.80/102.3

DANGER

Gaseous fuels such as natural gas and liquid propane (LP) gas are highly explosive. Even the slightest spark can ignite such fuels and cause an explosion. No leakage of fuel is permitted. Natural gas, which is lighter than air, tends to collect in high areas. LP gas is heavier than air and tends to settle in low areas.

1.9RECONFIGURING THE FUEL SYSTEM

◆1.9.1 7 KW, 410CC ENGINE

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

1.Turn the main gas supply off.

2.Remove the carburetor fuel hose from the outlet port of the demand regulator (Figure 1.3).

3.Disconnect wire #0 and wire #14 from the gas solenoid located on the top of the demand regu- lator.

4.Remove the demand regulator by rotating coun- terclockwise.

5.Remove the brass hose fitting from the outlet port of the demand regulator.

6.Remove the brass metering jet (loosen counter- clockwise) from the housing port of the demand regulator located on the side of the regulator.

7.Install new LP metering jet (tighten clockwise) in the outlet port of the demand regulator.

8.Refit the brass hose fittings to the outlet port of the demand regulator.

9.Reverse procedure steps 1-4 to reinstall demand regulator.

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

Figure 1.3 – Demand Regulator

	FUEL HOSE
FUEL HOSE	BRASS HOSE
	FITTING

BRASS HOSE

FITTING

OUTLET

PORT

FUEL JET

REGULATOR

HOUSING PORT

NG FUEL SYSTEM

LP FUEL SYSTEM

*Natural gas is in cubic feet per hour.

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

Generac® Power Systems, Inc. 7