90
<Output pulse signal and valve action>
Output(phase)
{
1
{
2
{
3
{
4
ON
ON
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
ON
ON
ON
OFF
OFF
ON
Output
A
E
D
C
B
Closie
Closie
Open
Open
Completely sealed (200 pulses)
Number of pulses
Valve fully open
at 2,000 pulses
V
alve position (volume)
Valve closing:1
➔
2
➔
3
➔
4
➔
1
Valve opening:4
➔
3
➔
2
➔
1
➔
4
The address of the pulse output is shifted using the procedures
mentioned earlier.
w
1. All output phase will turn OFF when the SLEV
w
2 stops
operating.
2. When the output phase is terminated or when the phase
shift is not according to frequency, the motor rotation will
become irregular, causing the motor to vibrate or lockup.
w
When the power supply is on, the closing signal of 2,200
pulse will be transmitted to decide the position of the valve.
The valve position can be determined when point
A
A
is
reached.
The LEV(SLEV
w
2) will not vibrate or make noise
when the valve is operating smoothly. However, when
the number of pulses change from
E
E
to
A
A
, or if the valve
lockup, there may be more noise than under normal
circumstances.
• The noise can be heard by resting your ear on the handle
of a screwdriver that is pressed against the top of the
LEV(SLEV
w
2) valve.
2
SLEV
w
2 action
3
Troubleshooting
Problem
Check point
Corrective measure
Remove the connector from the controller board and connect diagnostic
LEDs.
When power is turned on, pulse signals will output for 10 seconds.
There must be some defects in the operation circuit if the LED does not light
while the signals are output or keeps lighting even after the signals stop.
If the linear expansion valve (indoor unit) or electronic expansion valve
(outdoor unit) becomes locked and the motor is still operating, the motor will
emit a clicking noise and will not function. This clicking noise indicates
an abnormality.
Use an all-purpose electrical meter to measure the resistance between the
different coils (white-red, yellow-brown, orange-red, blue-brown). Normal
resistance is within a range of 150
'
±
10%.
In order to check the linear expansion valve, operate one indoor unit in the
fan mode and another in the cooling mode. Then, use the outdoor multi
controller board to operate the monitor and check the pipe temperature of the
indoor unit (liquid pipe temperature). The linear expansion valve should be
fully closed when the fan is operating. The temperature measured by the
temperature sensor will drop if there is any leakage.
If the measured temperature is significantly lower
than that on the remote controller, this indicates that
the valve is not closed. It is not necessary to replace
the linear expansion valve if the leak of refrigerant
is small and does not cause a malfunction.
1
Check improperly connected connector terminals and the wire colors.
2
Remove the connector on the controller board side and check electrical
conductance
Malfunction in microp-
rocessor operating
circuit
Locked expansion
valve
Short circuit or broken
circuit in expansion
valve motor coil
Valve does no close
completely
Incorrect connection
or connection failure
Replace the indoor unit
controller board or
Replace the outdoor
multi controller board.
Replace the linear
expansion valve or
electronic expansion
valve
Replace the linear
expansion valve or
electronic expansion
valve
Replace the linear
expansion valve if
there is a major leak
of refrigerant.
Continuity check of
wrong part.
6
5
4
3
2
1
1k
"
LED
Temperature
sensor
<liquid pipe>
Linear expansion valve
1
2
3
4
From the preceding page.
Only PUMY-125VMA model
w
2 LEV(A)
OC183E--3.qxp 10.5.6 3:05 PM Page 90
