Mitsubishi Electric PURY-EP200YLM-A, Service Handbook

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[8-9 Troubleshooting Problems with Major Components on BC Controller ]
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HWE1314A GB
8-9 Troubleshooting Problems with Major Components on BC
Controller
8-9-1 Pressure Sensor
Troubleshooting flow chart for pressure sensor
Check whether the pressure sensor or the
connectors of P1 and P3 are connected,
properly
All the compressors of the outdoor units to
which the BC controller is connected are stopped.
Check P1 and P3 on the self-diagnosis
LED, and check that the detected
pressure is 0.098MPa [14psi] or less.
On the self-diagnosis monitor, measure
Outdoor high-pressure 63HS1
Outdoor low-pressure 63LS
BC controller pressure P1 (liquid side)
and P3 (intermediate part)
Check whether the result is
63HS1 P1 P3 63LS
START
Repair the fault.
Fix the relation between
the refrigerant piping
and the transmission line.
Fix the relation between the
refrigerant piping and the
transmission line.
Replace the pressure sensor. Replace the board.
Restore contact failure.
Check whether the contact of the pressure
sensor connector in trouble is not faulty.
OK?
OK?
Check that the difference between each
detected pressure is 0.098MPa [14psi] or less.
OK?
Both the board and the pressure sensor are normal.
OK?
Is Pd P1 P3 Ps?
Remove the pressure sensor connector
from the board, and check the pressure.
OK?
OK?
Check whether the refrigerant pipe and the
transmission line are connected correctly
between the indoor unit and the BC controller.
OK?
Operating at the moment?
Check whether the refrigerant pipe
and the transmission line are
connected correctly between the indoor
unit and the BC controller.
OK?
YES
Note 2
Note 1
NO
YES
YES
YES
Note 3
Note 4
NO
NO
NO
NO
YES
NO
NO
YES
YES
YES
NO
NO
YES
NO
YES
NO
NO
Replace the pressure sensor, which detects
less than 6MPa [870psi] pressure, with the
pressure sensor, which detects 6MPa [870psi]
or more pressure, check the pressure, and
check whether the detected pressure is
displayed normally.
10 minutes or longer after
the operation stops?
Pressure 0MPa [0psi]
6MPa [870psi] pressure
or more is displayed.
Short-circuit between connecter pins #2 and #3
on the circuit board, and check the pressure.