Dometic 10 - Manual (Page 6)

There are two basic types of auxiliary air systems:
• Self-contained “package” units
• Split systems
The self-contained unit is designed to be wholly
mounted inside the truck, usually under a berth
or seat or inside a side storage locker. All of
the air conditioning components, including the
compressor, condenser, evaporator, blower and
power supply, are mounted on a single low-profile
chassis with an aluminum cover. The system’s
closed refrigerant loop is precharged and sealed
at the factory. Inside air is pulled across the
evaporator coil, and cooled air is blown through
a flexible duct to a discharge grill for discharge
into the living area. Hot air is discharged from the
condenser through cutouts in the floorboard.
Dometic’s patented split systems consist of two
separate modules. The outside unit contains
the condenser and cooling fan. It can be bolted
horizontally to the underside or vertically to the
back of the sleeper. The inside unit contains the
compressor, evaporator, blower, power-logic
box and other associated components.The
compressor is covered by a sheet-metal cover.
The inside unit is mounted under a berth or seat
or in a side storage locker. The two units are
connected by reusable precharged quick-connect
refrigerant linesets. The system is designed so
that both units automatically charge to the correct
refrigerant pressure as soon as the linesets are
connected. No special tools are required.
Each approach offers advantages and
disadvantages. A self-contained unit is simpler to
install and maintain, since it does not have any
external refrigerant lines. It is also less expensive
than a split system of the same BTU/hr capacity.
On the other hand, it takes more interior space,
and it requires cutting holes in the floor for air to
flow to and from the condenser. A split system, on
the other hand, has more installation flexibility and
uses less interior space. It also is quieter, since the
condenser fan is located outside the truck.
Both types of air conditioning systems are
available with a selection of built-in electrical
heat modules. The heat is blown through the
same ducts and grills and controlled by the same
thermostat. They can also be used in conjunction
with a diesel-fired heater if desired, under control
of the same thermostat.
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