Hitachi RAS-5HVRNM1E Service Manual page 319

8 Troubleshooting
• Checking procedure for the compressor
CHECK LIST ON COMPRESSOR
Client:
Serie No.
No. Check item
1 Is THM9 correctly connected?
THM9: Discharge Gas
Thermistor
2 Is thermistor THM9
disconnected?
3 Is current sensor faulty?
4 Is current sensing part on
PCB2 faulty?
5 Is the direction of current
sensor CTU, CTV) reverse?
6 Are power source wires, U and
V inserted correctly into
current sensor? .
7 Is exp. valve (MV1) correctly
connected?
8 Is exp. valve coil (MV1)
correctly connected?
9 Are the refrigeration cycle and
electrical wiring system
incorrectly connected?
10 Is opening of exp. valve
completely closed (locked)?
11 Is opening of exp. valve fully
opened locked)?
12 Are the contacts for comp.
magnetic switch CMC1 faulty?
13 Is there any voltage
abnormality among L1-L2, L2-
L3 and L3-L1?
14 Is the comp. oil acidified during
compressor motor burning?
311
SMGB0060 rev. 1- 12/2010
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 comp. is operating.
Td: Temperature of THM9
1. Check to ensure that thermistor on the top of
comp. is correctly mounted by viewing?
2. Check to ensure that actually measured temp.
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 Temp. (TL) < Air Intake Temp. (Ti)
during Cooling Operation
2. Liquid Pipe Temp. (TL) > Air Intake Temp. (Ti)
during Heating Operation
Check to ensure that liquid pipe temp. is lower
than air intake temp. of stopping indoor unit when
other indoor units are operating under cooling
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
8