Tiffin Motorhomes 2014 Allegro Bus, Owner'S Manual

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TIFFIN MOTORHOMES –ALLEGRO BUS® Chapter 3 HEATING & AIR CONDITIONING
3-7
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 overpressurization condition is eliminated.
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.
Figure 3-8. LP Gas Regulator
Caution
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.