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II. HEAT PUMP SIZING
The ability of a heat pump in the cooling mode to cool a
vehicle or maintain a consumer desired temperature is
dependent on the heat gain of the vehicle. The physical size,
the window area, the quality and amount of insulation, the
exposure to sunlight, the number of people using the vehicle
and the outside temperature, may increase the heat gain such
that the capacity of the air conditioner is exceeded.
As a general rule, air supplied (discharge air) in the cooling
mode will be 15 to 20 degrees F. (8 to 12 degrees C) cooler
than the air entering (return air) the ceiling assembly bottom
air grilles.
For example, if the air entering the heat pump is 80 degrees F.
(27 degrees C) (return air), the supply air (discharge air) into
the vehicle will be 60 to 65 degrees F. (15 to 19 degrees C).
As long as this temperature difference (15 to 20 degrees F, 8
to 12 degrees C) is being maintained, the unit is operating
properly.
Again, give careful consideration to the vehicle heat gain
variables. During extreme outdoor temperatures, the heat gain
of the vehicle may be reduced by:
Parking the vehicle in a shaded area
Keeping windows and doors closed
Avoiding the use of heat producing appliances
Using window shades (blinds and/or curtains)
For a more permanent solution to high heat gain situations,
additional vehicle insulation, window awnings and/or window
glass tinting should be considered.
III. SELECTING AN INSTALLATION LOCATION
Your Coleman-Mach heat pump has been designed for use
primarily in recreational vehicles.
Is the roof of the vehicle capable of supporting both the roof
top unit and ceiling assembly without additional support
structures? Inspect the interior ceiling mounting area to avoid
interference with existing structural members such as: bunks,
curtains, tracks or room dividers. The depth of the ceiling
assembly shroud is 51mm. Be sure to check clearance to
doors which must be swung open (refrigerator – closets -
cabinets).
Most of the time, roof mount heat pumps are installed at
existing roof vent locations. If there is no roof vent (existing
mounting hole), the following placement locations are
recommended.
Motorhomes – a single unit or the forward of two units should
be mounted within 2.7m of the driver compartment.
Travel Trailers or Mini-Homes – a location should be selected
that is near the door slightly forward of the vehicle center
length.
Vans – location should be in the center of the roof (side to
side – front to back).
Truck with Camper – location should be between 1.2 and
1.5m from the rear of the camper to achieve maximum cooling
effect.
IV. INSTALLING THE ROOF TOP UNIT
DANGER
SHOCK HAZARD
DISCONNECT ALL POWER TO THE VEHICLE
BEFORE PERFORMING ANY CUTTING TO THE
VEHICLE. CONTACT WITH HIGH VOLTAGE CAN
RESULT IN EQUIPMENT DAMAGE, PERSONAL
INJURY OR DEATH.
IMPORTANT
TO PREVENT DAMAGE TO THE WIRING AND
BATTERY, DISCONNECT THE BATTERY CABLE
FROM THE POSITIVE BATTERY TERMINAL
BEFORE PERFORMING ANY CUTTING TO THE
VEHICLE.
Once the location for your heat pump has been determined
(See Section III), a reinforced and framed roof hole opening
Once the location for your heat pump has been determined
(See Section III), a reinforced and framed roof hole opening
must be provided (may use existing vent hole). Before cutting
into the vehicle roof, verify that the cutting action will clear all
structural members and crossbeams. Additionally, the
location of any inner roof plumbing and electrical supplies
must be considered.
