Hitachi UTOPIA RAS-4HVRP2E - Checking Procedure for the Compressor

10 Troubleshooting
Checking procedure for main parts
SMGB0136 rev.0 - 07/2021
314
10.4.1.6 Checking procedure for the compressor
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Check list on compressor
Check list on compressor
Client:___________________________ Model: __________________________ Date: ______________________
Serial Nº: _______________________ Production date: __________________ Checker: ___________________
No. Check item Check method Result Remarks
1
Is THM9 correctly connected?
THM9: discharge gas thermistor
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
2 Is thermistor THM9 disconnected?
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.
3 Is current sensor faulty?
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.
4 Is current sensing part on PCB2 faulty?
5
Is the direction of current sensor (CTU,
CTV) reverse?
Check the direction => by viewing.
6
Are power source wires, U and V
inserted correctly into current sensor?
Check to ensure that wires are correctly inserted
7
Is expansion valve (MV1) correctly
connected?
Check to ensure that MV1 to CN5A is correctly
connected
8
Is exp. valve coil (MV1) correctly
connected?
Check to ensure that each coil is correctly mounted on
the valve.
9
Are the refrigeration cycle and
electrical wiring system incorrectly
connected?
Checktoensurethatrefrigerantisowingintoindoor
units by operating one refrigerating cycle only from the
outdoor unit.
10
Is opening of expansion valve
completely closed (locked)?
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
12
Are the contacts for compressor
magnetic switch CMC1 faulty?
Check the surface of each contact (L1, L2 and L3) by
viewing.
13
Is there any voltage abnormality
among L1-L2, L2-L3 and L3-L1?
Check to ensure that voltage imbalance is smaller than
3%.
Please note that power source voltage must be within
380V or 220V+10%.
14
Isthecompressoroilacidied
during compressor motor burning?
Check to ensure that the oil color is not black.