Checking Procedure For The Compressor - Hitachi UTOPIA RAS-4HVRP2E Service Manual

10 Troubleshooting
Checking procedure for main parts

10.4.1.6 Checking procedure for the compressor

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Check list on compressor
Client:___________________________
Serial Nº: _______________________
No. Check item
Is THM9 correctly connected?
1
THM9: discharge gas thermistor
2 Is thermistor THM9 disconnected?
3 Is current sensor faulty?
4 Is current sensing part on PCB2 faulty?
Is the direction of current sensor (CTU,
5
CTV) reverse?
Are power source wires, U and V
6
inserted correctly into current sensor?
Is expansion valve (MV1) correctly
7
connected?
Is exp. valve coil (MV1) correctly
8
connected?
Are the refrigeration cycle and
9 electrical wiring system incorrectly
connected?
Is opening of expansion valve
10
completely closed (locked)?
Are the contacts for compressor
12
magnetic switch CMC1 faulty?
Is there any voltage abnormality
13
among L1-L2, L2-L3 and L3-L1?
Is the compressor oil acidified
14
during compressor motor burning?
314 SMGB0136 rev.0 - 07/2021
Check list on compressor
Model: __________________________
Production date: __________________
Check method
1. Is wire of thermistor correctly connected by viewing?
2. Check to ensure the 7-segment indication of Td when
compressor is operating.
Td: temperature of THM9
1. Check to ensure that thermistor on the top of
compressor is correctly mounted by viewing?
2. Check to ensure that actually measured temperature
is the same as the indication during check mode.
1. Check to ensure that indication A1 and A2 are 0
during compressor stopping.
2. Check to ensure that indication A1 and A2 are not 0
during compressor running.
Check the direction => by viewing.
Check to ensure that wires are correctly inserted
Check to ensure that MV1 to CN5A is correctly
connected
Check to ensure that each coil is correctly mounted on
the valve.
Check to ensure that refrigerant is flowing into indoor
units by operating one refrigerating cycle only from the
outdoor unit.
Check the following by the check mode of outdoor units.
1. Liquid pipe temperature (TL) < Control information B2
during cooling operation
2. Liquid pipe temperature (TL) > Control information B2
during heating operation
Check the surface of each contact (L1, L2 and L3) by
viewing.
Check to ensure that voltage imbalance is smaller than
3%.
Please note that power source voltage must be within
380V or 220V+10%.
Check to ensure that the oil color is not black.
Date: ______________________
Checker: ___________________
Result Remarks