Service manual

7
The power supply to the air conditioner must be wired
through a circuit breaker or time delay fuse. The power
supply must be 20 amperes and 12 AWG wire minimum.
Any size
larger at any time may be used and should be used if the
length of the wire is over 32 feet.
2) Color Code
The electric power from the electric service panel should be
delivered through a 3 conductor cable and the Service
Technician should check to be sure the color code is correct.
The electrician probably installed the cable with the colors
according to code, but don’t bet your life on it.
a) The wire with black insulation is the hot
wire and there should be 115 volts
(domestic USA) between it and either of the
other wires. All switches, fuses, circuit
breakers, disconnects, etc. should be in this
line.
b) The wire with the white insulation is the
neutral. There should be 115 volts
(domestic USA) between the neutral and the
hot (black) wire, but there should be 0 volts
between the neutral and the ground (the
green wire or the frame of the air
conditioner). There must be no switches,
fuses, disconnects, etc. of any kind in the
neutral wire.
c) The third wire may be covered with green
insulation or it may be a bare metal wire. It
is the ground wire. There must be 115 volts
(domestic USA) between this wire and the
hot (black) wire and 0 volts between it and
the neutral (white) wire. The ground wire
must be securely fastened to the air
conditioner cabinet. A ground screw is
provided for this purpose.
3) Voltage
The voltage (electrical pressure) at the unit should be
115 volts (domestic USA) and all electrical components will
perform best at the correct voltage. However, the voltage will
vary and the air conditioning system will perform
satisfactorily within plus or minus 10% of the rated (115)
voltage (domestic USA). Therefore, the voltage has to be
between 103.5 volts and 126.5 volts.
3. Power Supply - Generated by on-board motor
generator
If the power supply for the recreational vehicle is supplied by
an on-board motor generator, its wiring may be identical to
the commercial power described above.
There are, however, some motor generators on which both the
current carrying leads are insulated from the ground. That is
to say; there is no grounded neutral, so there will be 115 volts
(domestic USA) between the black and white leads, but there
will be 0 volts between either lead and ground.
WARNING: The service technician must keep in mind
when checking to make sure that the power is turned off.
Check only between the hot (black) lead and the neutral
(white) lead.
4. Selector Switch - Free Delivery Ceiling Assemblies
The selector switch is mounted on the left side of the interior
ceiling assembly. The selector switch allows the unit to be
operated on high to low blower only, or high to low blower
with compressor operation for cooling. On heating and
cooling models, the selector switch can also switch in the
electric heater at low blower operation only.
To check the selector switch, remove wires from the terminals
and rotate the switch to the proper position and read
continuity as follows:
Terminals Switch Position
L-1-3 Lo Heat
L-1 Lo Fan
L-2 Hi Fan
L-1-4 Lo Cool
L-2-4 Hi Cool
* If you do not wish to remove the wires from each terminal,
disconnect the 9 pin plug from the a/c unit.
5. Thermostat (Mechanical Rotary)
The thermostat (temperature controller) is mounted on the
right side of the interior ceiling assembly. The thermostat
controls the on-off cycle of the compressor when the selector
switch is in the cooling position and on heating and cooling
models, the on-off cycle of the electric heater when the
selector switch is in the heating position. The thermostat is
actuated by sensing the temperature of the return air through
the vent where the bulb is located. Terminal continuity
should make and break if ambient air temperature is between
65 and 90 degrees F.
6. Compressor Motor
The compressor motor is located inside the hermetic
compressor housing and therefore not accessible for service or
visual observation in the field. However, the motor winding