Generac Power Systems NP-40G - Manual (Page 68)

Section 4.1- INTRODUCTION TO FUEL SYSTEM
General Information
Some RV generator models are equipped with
fuel systems that utilize LP gas as a fuel. The
Initials “LP" stand for "liquefied petroleum". This
gas Is highly volatile and can be dangerous if han­
dled or stored carelessly.
All applicable laws, codes and regulations per­
taining to the storage and handling of LP gas must
be complied with. The installation of such fuel
systems must also be In compliance with such
laws, codes and regulations. Service technicians
who work on these systems must do nothing that
might cause the system to be In non-compliahce
with regulations.
Regulations established by the Recreational Ve-
hiclelndustry Association (RVIA) must be followed
in the installation, use and servicing of such sys­
tems.
DANGERI
LP GAS IS HIGHLY EXPLOSIVE. THE GAS IS
HEAVIER THAN AIR AND TENDS TO SETTLE IN
LOW AREAS. EVEN THE LIGHTEST SPARK CAN
IGNITE THE GAS AND CAUSE AN EXPLOSION.
ONLY COMPETENT, QUALIFIED GAS SERVICE
TECHNICIANS SHOULD BE ALLOWED TO IN­
STALL, TEST, ADJUST OR SERVICE THE GAS­
EOUS FUEL SYSTEM. INSTALLATION OF A GAS­
EOUS FUEL SYSTEM MUST BE IN STRICT COM­
PLIANCE WITH APPLICABLE CODES. FOLLOW­
ING INSTALLATION NOTHING MUST BE DONE
THAT MIGHT RENDER THE SYSTEM IN NON-
COMPLIANCE WITH SUCH CODES.
DANGERI
USE ONLY APPROVED COMPONENTS IN THE
GASEOUS FUEL SYSTEM. IMPROPER INSTAL
LATION OR USE OF UNAUTHORIZED COMPO
NENTS CAN RESULT IN FIRE OR AN EXPLOSION
USE APPROVED METHODS TO TEST THE SYS
ТЕМ FOR LEAKS. NO LEAKAGE IS PERMITTED
DO NOT PERMIT FUEL VAPORS TO ENTER THE
VEHICLE INTERIOR.
Advantages of Gaseous Fuels
The use of gaseous fuels may result In a slight
power loss, as compared to gasoline. However,
that disadvantage Is usually compensated for by
the many advantages of gaseous fuels. Some of
these advantages are:
□ A low residue content results in minimum car­
bon formation in the engine.
□ Reduced sludge buildup in the engine oil.
□ Reduced burning of valves as compared to
gasoline.
□ No wash-down of engine cylinder walls during
cranking and startup.
□ Excellent anti-knock qualities.
□ A nearly homogeneous mixture In the engine
cylinders.
□ Fuel can be stored for long periods without
breakdown.
Fuel System Components
When the generator set is shipped from the fac­
tory, the following feui system components are
Included with the unit:
1. A Fuel Lockoff Solenoid
2. The LP Gas Regulator
3. The carburetor.
4. Interconnecting lines and fittings.
Components that must be added by the genera­
tor installer include the following:
1. A VAPOR WITHDRAWAL type fuel tank.
2. A PRIMARY REGULATOR that will deliver a
fuel pressure to the Fuel Lockoff Solenoid of
about 11 psi.
3. Interconnecting lines and fittings.
Vapor Withdrawal
LP gas Is stored in pressure tanks as a liquid.
Gaseous fuel system components Installed on the
generator are designed for "vapor withdrawal" type
systems. Such systems use the gas vapors that
form above the liquid fuel In the tank. Do not at­
tempt to use any "liquid withdrawal" type tank with
the RV generator.
NOTE: "Liquid withdrawal" type systems use the
liquid fuel from the tank. The liquid fuel must be
vaporized before It reaches the carburetor. Fuel
vaporization Is usually accomplished by porting
the liquid fuel through some kind of heating device.
Important Considerations
When servicing the gaseous fuel system the fol­
lowing rules apply:
□ All lines, fittings, hoses and clamps must be
free of leaks. Apply pipe sealant to threads
when assembling threaded connectors to re­
duce the possibility of leakage.
□ Following any service, the system must be
tested for leaks using APPROVED test meth­
ods.
□ Optimum gas pressure at the Inlet to the fuel
lockoff solenoid and secondary regulator Is 11
inches of water column. Do NOT exceed 14
inches water column.
Page 4.1-1