– 61 –
3-Way Valve
The 3-way valve is located in the machine
compartment between the compressor and the
condenser fan.
The capillary tubes on the refrigerator are color
coded on the tubing.
The fresh food capillary tube is on the left and color
coded with RED.
The freezer capillary tube is on the right and is color
coded with BLUE.
Inverter
The inverter controls compressor speed by
frequency variation and by Pulse Width Modulation
(PWM). Changing frequency and PWM will cause
an effective voltage between 80 and 240 VAC to
be received at the compressor. Frequency will vary
from 40Hz low speed up to 151Hz at high speed.
The inverter receives commands from the main
control board. The main control board will send a
PWM run signal from the J9 connector pins 7 to
8 of 2-3 VDC (effective voltage) to the inverter (all
wires must be connected). The inverter will select
compressor speed (voltage output) based on this
signal. The PWM run signal voltage can also be
checked at the inverter harness. The main control
board will only send a run signal to the inverter
when the compressor should be on.
Note:
When measuring signal voltage (from the
main control board) at the inverter, a reading of 4-6
VDC will be measured with all wires connected. If the
inverter wiring is disconnected, the board output will
measure between 4-5 VDC.
The inverter will monitor compressor operation and
if the compressor fails to start or excessive current
draw (4 amps maximum) is detected, the inverter
will brie
fl
y stop voltage output. The inverter will then
make 12 consecutive compressor-start attempts
(once every 12 seconds). After 12 attempts, if the
compressor has not started, an 8-minute count
will initiate. After the 8-minute count, the inverter
will attempt to start the compressor again. If the
compressor starts, normal operation will resume.
If the compressor fails to start, this process will be
repeated. Removing power to the unit will reset
the inverter count. When power is restored, the
inverter will attempt to start the compressor within
8 minutes.
The inverter has built-in circuit protection to
guard against damage from a failed or shorted
compressor. However, if a failed compressor is
diagnosed, order a new compressor and inverter.
Replace the inverter
fi
rst. If the compressor fails
to start after inverter replacement, replace the
compressor.
(
Continued next page
)
The 3-way valve is used to direct refrigerant
fl
ow.
The valve has 4 different positions.
They are referred to by the letters A, B, C, and D.
A = Open to the fresh food and freezer evaporators
in series (Refrigerant
fl
ows thru the fresh
food evaporator and then into the freezer
evaporator.)
B = Open to the freezer evaporator only
C = Open to both the fresh food and freezer
evaporators via the individual capillary tubes
(This position is not currently used on these
models for cooling.)
D = Closed to both fresh food and freezer
evaporators during the off cycle (This is also
called the home position.)
Fresh Food
Capillary Tube
Freezer
Capillary
Tube
