Wiring The Unit; Ducting The Supply Air - Dometic Kohler 7APU Operation And Installation

Controls
Two types of controls are used with these self-contained
units. Model ASCF7 has a built-in mechanical control. All
other models use the SMXir digital keypad/display which is
sold separately.
If you have model ASCF7, then read the below section
"Mechanical Controls" and ignore all information on the
SMXir control. Review the sections "Troubleshooting" and
"System Maintenance" for future reference.
If your system uses the SMXir digital keypad/display, then
you may skip the "Mechanical Controls" section and start
with the section "SMXir Controls", reading through to the end
of this manual.
Mechanical Controls
The mechanical control on model ASCF7 is built-in and
requires no additional installation. To operate the mechanical
control, follow these instructions:
1. Turn power on to the system.
2. Set the thermostat to the coldest setting by rotating it fully
clockwise.
3. Set the FAN/COOL selector switch to HI COOL.
4. Close all doors and windows to your sleeper compart-
ment.
5. Once the temperature reaches a comfortable level, rotate
the thermostat slowly counterclockwise, stopping at the
point where the unit cycles off. That is now the setpoint.
The fan will run faster on HI COOL and slower on LO COOL
as the system cycles on and off in the cooling mode. Or, if
you just want the fan only, then choose the LO FAN or HI
FAN settings. Model ASCF7 with the mechanical control
does not supply heat.
SMXir Controls
The SMXir digital keypad/display may be mounted in any
convenient location, on a bulkhead or in a cabinet or closet,
for instance. Choose a location that is easy to reach, but not
in the way of daily routines. Make sure that the mounting
location is within the display cable (CXP) length of the A/C
unit. Route the CXP cable prior to mounting SMXir control.
Use the enclosed instructions for mounting the SMXir. Drill a
hole for the CXP cable to feed through. Mount the display
backing plate centered over that hole. Run the cable through
the hole and plug it into the display. Then snap the display
onto the backing plate, being careful not to crimp the cable.
The other end of the CXP should be plugged into the SMX
circuit board/elec box socket marked "DISPLAY". The other
L-2347K Installation
cable that is plugged into the SMX circuit board/elec box is
the TSEP (temperature sensing element). That cable is
mounted on the unit in front of the evaporator coil in the
return air stream and is plugged into the socket marked
"TEMP". CXP cables are available in a variety of lengths,
please contact your dealer if need be. Although the CXP
looks like a standard telephone cable, it is not; phone cables
will not work as a display cable. Access the elec box by
removing the panel on the end of the unit, above the cable
feed-thru holes.
Warning
Make sure all power is off before opening any
electrical box.
Warning
The SMX interconnect (C XP) and temperature sensor
cables (TSEP) transmit low voltage DC signals, and
outside interference can affect their operation. Do not
route these cables beside A/C power cables, high
voltage wiring, or antenna wires. Keep the cable runs as
short as possible to reduce the chance of interference.

Wiring The Unit

Warning
Care must always be exercised when dealing with
electricity. Wiring should be done only by a qualified
technician. Contact an electrician if you have any
questions.
Refer to the wiring diagrams in the back of this manual or the
diagram that is located inside the electrical panel of the unit.
The unit should be wired according to power requirements
given on the data plate and per NEC recommendations. The
unit must alwasy be grounded. Always refer to NEC or state/
local codes for further wiring recommendations.

Ducting The Supply Air

The supply air grill should be mounted in a place that will
allow for the best air distribution, preferably up high. Locate
the best place to mount the grill and verify that you have
enough duct to cover the length between the unit and the
grill. Cut out for the grill, and mount securely. Use the large
hose clamps to secure the duct to the unit and to the back of
the grill. Air discharged through low-mounted grills should be
directed upward by tuning the louvers 45° up.
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English