Appliances – Airstream 390 User Manual
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APPLIANCES
REFRIGERATOR
Manufacturer:
Dometic Sales Corporation 2320
Industrial Parkway P.O. Box 490
Elkhart, Indiana 46514
Phone: 219-295-5228
Review all Dometic Literature supplied in your Owner’s Packet or stored in the refrig-
erator prior to operating.
In the absorption refrigerant system, ammonia is liquefied in the finned condenser coil
at the top rear of the refrigerator. The liquid ammonia then flows into the evaporator
(inside the freezer section) and is exposed to a circulating flow of hydrogen gas, which
causes the ammonia to evaporate, creating a cold condition in the freezer.
The tubing in the evaporator section is specifically sloped to provide a continuous
movement of liquid ammonia, flowing downward by gravity, through this section. If the
refrigerator is operated out-of-level when the vehicle is not moving, liquid ammonia
will accumulate in portions of the evaporator tubing. This will slow the circulation of
hydrogen and ammonia gas, or in severe cases, completely block it, resulting in a loss
of cooling.
Any time the vehicle is parked for several hours with the refrigerator operating the ve-
hicle should be leveled to prevent this loss of cooling. The vehicle needs to be leveled
only so it is
comfortable to live in (no noticeable sloping of floor or walls).
When the vehicle is moving the leveling is not critical, as the rolling and pitching move-
ment of the vehicle will pass to either side of level, keeping the liquid ammonia from
accumulating in the evaporator tubing.
OPERATION
The refrigerator requires 12-volt current to operate even if running on LP or 110 volt
modes. The 12-volt currrent is supplied by the coach batteries and is used to power
the circuit board that directs the refrigerator functions. When running in a mode such
as LP, it means the heat source, by far the largest power requirement; to evaporate
the ammonia is being provided by an LP Gas burner.
WARNING
: Most LP gas appliances used in recreational vehicles are vented
to the outside of the vehicle. When parked close to a gasoline pump, it is possible that
gasoline fumes could enter this type of appliance and ignite the burner flame, CAUS-
ING A FIRE OR AN EXPLOSION.