Mitsubishi Electric City Multi CMB-P1016NU-G, Service Handbook

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[
IX
Troubleshooting ]
(2) Solenoid valve (SVA, SVB, SVC)
Stop the operation of the applied
BC remote controller system.
Faulty judgment of solenoid valve
Faulty judgment of solenoid valve Solenoid valve failure
Replace the control board. Replace the solenoid valve coil.
Repair the fault.
Replace the control board.
Stop the operation
Note 1
Check whether the wire to the
solenoid valve is not connected
wrongly, or the connector is not loose.
No fault
Check the operation sound of the solenoid
valve to be magnetized at the time of
turning on the remote controller.
Makes a tick sound.
Check the relay output with the
self-diagnosis LED, and check
whether the operation corresponds
with the operation mode.
Corresponds
Measure the temperature at the upstream
and downstream pipes of the solenoid valve.
When the solenoid valve is ON : There is no temperature difference.
When the solenoid valve is OFF : There is a temperature difference.
OK
Remove the solenoid valve coil, and
check that there is a suction force.
There is a suction force.
Note 2
Note 2
Note 2
Measure the temperature at the upstream
and downstream pipes of the solenoid
valve, and compare them.
There is no temperature difference. : OK
There is a temperature difference. : NO
OK
Run the cooling or heating operation
of the refrigerant system of the
solenoid valve in trouble.
NO
NO
NO
Stop the unit with the remote controller.
Remove the solenoid valve connector, and
check that the electricity runs through the
solenoid valve coil.
The electricity runs.
Output 208 / 230V
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
Turn on the remote controller with the
connector of the solenoid valve in trouble
is disconnected, and check that the control
board outputs 208 / 230V.