146
Propane Systems
SECTION EIGHT
• Each liquid gallon of propane produces 91,502
BTUs (British Thermal Units) .
• Temperature affects pressure of propane . Internal
tank pressure can exceed 200 psi .
• Tanks or valves contain pressure relief valves . The
relief valve opens at 125% above tank rating .
• Propane stops vaporizing at -44˚ F . Standard
propane operating pressure is 11” of Water Column
or approximately 6 1/4 ounces per square inch .
• An inch of Water Column is a measurement of
applied pressure to one side of a U-Tube 1/2 filled
with water at sea level . The amount of pressure
required to raise the water level 11”, represents 11”
of Water Column .
PROPANE REGULATOR
Propane is compressed into liquid form in the tank .
Only the vapor (gas) is used during combustion by
an appliance . As vapor is removed from the tank, the
remaining liquid will vaporize to maintain pressure
that is removed during consumption . This process will
continue until there is no liquid remaining in the tank .
Temperature affects the vaporizing action of the liquid .
If temperature of the liquid is - 44º F, vaporization
of liquid is nearly stable with tank pressure about 0
psi . If liquid temperature is 100º F ., the liquid quickly
vaporizes with tank pressure about 200 psi . Vapor
pressure must remain relatively consistent, regardless
of temperature, for the appliance heat output to remain
stable . Vapor pressure regulation is performed by the
regulator .
050251
From Tank
To Appliances
Vent
Second Stage
Low Pressure
Regulator
First Stage
High Pressure
Regulator
050250d
Cover
Primary Valve
Regulator
Fill
Bleed Valve
Propane Statistics
Pounds Per Gallon
4.24
Specific Gravity of Gas
1.5
Specific Gravity of Liquid
.504
Cubic Feet Gas Per Gallon of Liquid
36.38
Cubic Feet Gas Per Pound
8.66
BTUs Per Gallon
91,502
BTUs Per Gallon
21,548
Dew Point in Degrees Fahrenheit
-44°F
Vapor Pressure at 0˚° F
31
Vapor Pressure at 70˚° F
127
Vapor Pressure at 100˚° F
196
Vapor Pressure at 110˚° F
230
Flash Point
842° F
WARNING:
Before entering a refueling station, turn off all pilot
lights and propane operated appliances . Most
propane appliances are vented to the outside . Fuel
vapors can enter an appliance vent that is parked
close to a gasoline pump and ignite the vapor,
resulting in an explosion or fire .
NOTE:
The propane fundamentals information is not a
complete guide for the use of propane tanks or
appliances . In cold climates keep propane level
above 50% to keep vaporization of propane at the
highest level .
Summary of Contents for Class A Gas 2020
Page 173: ...FLEETWOOD RV CLASS A GAS 2020 OWNER S MANUAL 171...
Page 174: ...172 Notes...
