Mitsubishi Electronics PUHY-P312 Air Conditioner User Manual


 
[ IX Troubleshooting ]
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HWE08040 GB
2) PUHY-P120THMU-A
DC24
~
30V
YES
NO
NO
NO
NO
Check the voltage at the indoor/outdoor
transmission terminal block (TB3) of outdoor unit.
DC 24 ~ 30 V
DC 24 ~ 30 V
Check the voltage at TB3 after removing transmission
line from TB3.
Check whether the male connector is connected to
the female power supply connector (CN40).
Connected
Check voltage of terminal block for centralized control (TB7).
YES
YES
YES
Check if the indoor/outdoor transmission line is not
short-circuited, and repair the problem.
Check whether the transmission line is disconnected,
check for contact failure, and repair the problem.
Check the voltage between No.1 and No.2 pins of the
CNS2 on the control board.
Check the voltage between No.1 and No.2 pins of the
CN102 on the power supply board for the transmission line.
DC24
~
30V
DC24
~
30V
DC24
~
30V
NO
NO
Check voltage of TB7 by removing transmission line from TB7.
YES
YES
YES
NO
Check the wiring between the control board and power
supply board for the transmission line (CN102 and CNIT),
and check for proper connection of connectors.
Fix the wiring and connector
disconnection.
Check for shorted transmission
line for centralized control.
YES
Is there a wiring
error or a connector
disconnection?
Replace the control board.
Check the wiring between the control board and power
supply board for the transmission line (CN102 and CNIT),
and check for proper connection of connectors.
Check the voltage between No.5 and No.2 pins
of the CNIT on the control board.
Is the voltage
measurement between
4.5 and 5.2 VDC?
Is there a connector
disconnection?
Fix the connector disconnection.
Replace the M-NET board
Replace the M-NET board
YES
YES
YES
YES
YES
YES
YES
NO
NO
Replace the INV board.
Replace the noise filter.
Replace the noise filter.
Replace the diode stack.
Check and fix any power supply wiring and main power
supply problems found.
Turn on the
power again.
Check the voltage between No.1 and No.3 pins of
the CNDC3 on the INV board.
Check the voltage between TB31 and TB42 on the noise filter.
Check the voltage between the + and – terminals
on the diode stack.
DC265
~
357V
DC265
~
357V
DC265
~
357V
NO
NO
NO
Check the voltages among TB21, TB22, and
TB23 on the noise filter.
Check the voltage at the power supply terminal block TB1.
AC188
~
253V
AC188
~
253V
NO
NO
NO
[THMU-A]