Airstream INTERNATIONAL TRAILER, Owner'S Manual

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AIRSTREAM INTERNATIONAL TRAILER OWNERS MANUAL
F-1
PLUMBING SYSTEM
LIQUID PETROLEUM GAS (LPG)
FILL VALVE
Your trailer is equipped with LP tank fill valves called "RV Type I Acme" connection. The large, green,
nylon swivel nut is a right hand thread and is designed for
hand operation only .
The valve features an internal spring-loaded module that will not allow gas to flow from the cylinder until a
positive seal has been made at the connection. The valve outlet has 1-5/16" Acme threads on the outlet
exterior and female POL, left-handed threads on its interior. This feature allows for connection of the new
wrenchless, right-handed, Acme RV connection and still accommodates the standard left-handed POL
fittings used for filling propane cylinders.
The mating, green swivel nut and brass nipple also incorporates new features: the green nylon nut swivels
on a black bushing that is heat sensitive. Between 240 degrees F and 300 degrees F the bushing will yield
(melt) allowing the spring-loaded module in the valve to push the brass nipple back (approximately 1/4")
closing the module and stopping the flow of gas from the cylinder. Inside the brass nipple is a flow-limiting
device designed to sense excessive gas flow. If an excessive flow is sensed, the flow-limiting device shuts
the flow down to a maximum of 10 SCFH (Standard Cubic Feet per Hour) or less. This is also referred to
as the by-pass flow.
By-pass flow is extremely important in the proper operation of this connection. The flow-limiting device
may activate if the cylinder valve is opened quickly. When all appliances are off, the by-pass flow allows
the pressure downstream from the flow-limiting device to equalize. When pressure is equalized, the flow-
limiting device will supply normal flow to the system. Equalization occurs in approximately 5 seconds and
in most cases goes completely unnoticed. If, however, an appliance is left on or there is a leak or open flow
in the system, the by-pass pressure will not be able to equalize and allow the flow-limiting device to re-
open. Symptoms of this condition would be appliances that light but have lower than normal flame or
starve out from lack of gas, a substantial reduction in the flame when another appliance is operating, or
pilots that are difficult to light. If this should happen, the following steps should eliminate the condition:
1.
Close LP cylinder valve.
2. Extinguish all flames and smoking materials
3. Be sure all gas appliances, including their pilot lights, are off.
4. Open LP cylinder valve slowly. DO NOT SNAP OPEN.
5. Wait at least 15 seconds before lighting appliances.
6. If operational difficulties continue, there may be a leak in the system. Immediately close the LP
cylinder valve and have the system inspected by a qualified RV service technician.
Again, make sure all appliances are off before opening propane cylinder valves.
Exception: when reconnecting a full cylinder to an auto changeover regulator it is not necessary to
shut off the appliances or close the valve of the cylinder already in service.
WARNING
: LEAKING LP GAS MAY IGNITE CAUSING A FIRE OR EXPLOSION
WHICH COULD RESULT IN SERIOUS BODILY INJURY, PROPERTY DAMAGE, OR DEATH.
How long a full tank of gas will last is dependent on usage. In cold weather, when you are using the
furnace, large amounts of hot water, and are doing extensive cooking, you will naturally use more than you
will in warm weather when you may do limited cooking. On the average, with normal cooking and other
appliance use you can probably count on two to three weeks of service from each tank.