Winco PSS20000/C - Manual (Page 7)

PAGE 5
that the unit was set up and tested on. A slight adjust-
ment may be necessary on NG depending on local BTU
content. This adjustment will be discussed later.
Line Size
Unit location will determine the size of fuel line that is
required to supply the engine with a constant fuel
pressure and volume. Refer to the tables below for fuel
line size, fuel consumption and recommended tank size.
For distances of 50 feet and over, a two regulator fuel
system is recommended. This is accomplished by
installing a primary regulator at the tank which will reduce
the tank pressure down to 10 to 15 lbs. A secondary
regulator is installed to further reduce the fuel pressure
to the required four (4) to six (6) oz operating pressure.
This secondary regulator must be at least 10 feet from
the engine generator set, any closer installation will
require a larger line be installed to provide a fuel reser-
voir. This is also true for the single dual stage regula-
tors, they should also be minimum of 10 feet form the
unit. If this is not done the demand regulator on the unit
and the pressure regulator in the fuel line will interfere
with each other. When this two (2) stage regulator
system is used, a fuel line size of 1/2 to 5/8 inch is
generally adequate for distances up to 300 feet from the
primary to the secondary regulator. (Consult your local
fuel supplier for your exact requirements.) The appropri-
ate line size from the table below is then installed from
the second regulator to the generator set.
*************
***** WARNING ****
*************
PERSONAL DANGER - Do not use galvanized pipe in
fuel line runs. The galvanized coating can become
eroded and flake off, causing possible obstructions in the
regulator or fuel valve. The results could range from
inoperative engine start to hazardous fuel leaks.
NATURAL GAS or LP VAPOR
Size of pipe normally required for generators operating
on NATURAL GAS or LP VAPOR
up to 25 feet* 25 - 100 feet* over 100 feet*
PSS8000 3/4" pipe 1" pipe not recommended
PSS12000 3/4” pipe 1” pipe use a two
PSS20000 1" pipe 1.25" pipe regulator system
*Allow an additional 3 feet for each standard elbow. Do not use
‘street ells’ (restrictive)*
LP LIQUID WITHDRAWAL (ONLY)
Size of pipe normally required for generators operating
on LP LIQUID WITHDRAWAL
PSS20000 - 3/8” line for all distances.
**** CAUTION ****
Be careful when sealing gas joints. Excessive sealing
compound can be drawn into the solenoid, regulator or
carburetor causing an engine malfunction.
FUEL PRESSURE
L.P. & N.G. VAPOR FUEL
Correct fuel pressure cannot be stressed enough. The
most common cause for inoperative systems is an
inadequate or incorrect fuel pressure. Performance of
the engine is in direct relation to the correctness of the
fuel system. Shown below is a block diagram of a
typical L.P. or N.G. vapor fuel installation.
Notice the following tables give two (2) different units of
measuring fuel pressure. The first and most accurate is
the use of a simple water manometer. A manometer is
calibrated in inches of water column. The second is with
a pressure gauge calibrated in ounces per square inch.
TWO (2) REGULATOR FUEL SYSTEM
Supply Primary Secondary Generator
Tank Regulator Regulator Set
1 2 3 4
SINGLE REGULATOR FUEL SYSTEM
Supply Primary Generator
Tank Regulator Set
1 3 4
Reference numbers 1 through 3 in the block diagrams
above are system parts supplied by customer.
Reference number 4 is the engine generator set.
Below is a table of the fuel pressure reading at each
reference in the system.
Fuel Pressure Table
Single Regulator (L.P. Vapor only)
1 3 4
UNIT OFF TANK PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
STARTING TANK PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
NO LOAD TANK PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
FULL LOAD TANK PSI 7-11 in 7-11 in
4-6 oz 4-6 oz
Two (2) Regulator System (L.P. Vapor only)
1 2 3 4
UNIT OFF TANK PSI 10-15 lbs 7-11 in 7-11 in
4-6 oz 4-6 oz
STARTING TANK PSI 10-15 lbs 7-11 in 7-11 in
4-6 oz 4-6 oz
NO LOAD TANK PSI 10-15 lbs 7-11 in 7-11 in
4-6 oz 4-6 oz
FULL LOAD TANK PSI 10-15 lbs 7-11 in 7-11 in
4-6 oz 4-6 oz