Lp Tank Filling Practices; Lp Gas Regulator - Tiffin Motorhomes Allegro Bus 2011 Owner's Manual

H E A T I N G & A I R C O N D I T I O N I N G
Warning
When the motor home is not being used, the main LP gas valve must be turned "off."
Also, turn "off" the main valve when the LP gas tank is to be refueled to avoid the
possibility of ignition fuel fumes by the pilot lights. All gas valves on the gas-operated
appliances with Direct Spark Ignition (DSI) should also be in the "off" position during
refueling and/or maintenance operations. DO NOT store LP, motor fuel, propane,
butane, or other flammable liquids inside the motor home as these represent a very
real fire hazard and possible threat to life.

LP Tank Filling Practices

Any LP gas tank associated with the motor home should never be filled to more than 80% of total
capacity; filling should always be done only when the motor home is leveled. If the motor home is not
level, the tank may be overfilled (i.e., more than 80% of capacity) and, thus, subject the motor home to
possible fire or explosion from resultant uncontrolled gas flows.

LP Gas Regulator

As noted earlier, the LP gas regulator (Figure 3-8) is the "heart" of the LP gas distribution system. This
regulator reduces and controls the pressure of the gas on the outlet
end to provide a constant supply of gas at a constant pressure to the
gas-operated appliances.
The regulator has a vent to relieve excess pressure on the inlet side of
the regulator, should excess pressure develop in the gas tank and
connecting gas line to that regulator inlet. The vent would normally
release the excess LP gas to the atmosphere until the over-
pressurization condition is eliminated.
Figure 3-8. LP Gas Regulator
This vent should be regularly checked to assure that it is not clogged or obstructed. If that vent is
blocked from normal operation, component or system failures may result. If periodic visual inspection
indicates any sign of corrosion or degradation, contact a qualified service technician to repair the
regulator as soon as possible; DO NOT operate the LP gas system with any faulty component in place.
Occasionally, the inherent moisture in the LP gas can cause a freeze-up of the regulator when the gas
passes through the regulator. The regulator reduces the high pressure of the gas on its inlet side to a
reduced pressure on its outlet side by permitting a controlled expansion of the gas through the
regulator—this gas expansion necessarily cools the gas (by means of the Joule-Thompson effect) and, if
cooled enough, may cause any moisture content to freeze.
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