MULTI TYPE

Check items and procedures to follow when checking oil circuit with compressor(s) disconnected
Check item Location Procedure
Leakage of outdoor PMV
Leakage of check valve in
discharge pipe convergent
section
Leakage of check valve in
discharge pipe
Leakage of check valve in oil
equalization circuit
Leakage of SV3A valve
Leakage of SV3B valve
Clogging of SV3E valve
Clogging of oil-return distributor
Clogging of SV3D valve
Clogging of oil-return capillary
Clogging of oil-return distributor
A,B
C,D
E
F
G
H
I
J
1) With PMV1, 2 and 4 fully closed, apply pressure to the check joint of liquid pipe with nitrogen, and check the
pressure at the check joint of discharge pipe.
If the pressure at the check joint of discharge pipe increases, there is a leak from PMV1, 2 or 4 (A, B) and either
discharge pipe check valve (C, D). Replace the faulty parts.
2) If the pressure does not increase, fully open outdoor PMV 1 and 2 and check the pressure at the check joint of
discharge pipe again.
If the pressure increases, there is a leak from the check valve of discharge pipe (D). Replace the part.
With just PMV4 fully opened, check the pressure at the check joint of discharge pipe again.
If the pressure increases, there is a leak from the check valve of discharge pipe (C). Replace the part.
3) With pressure applied to the check joint of discharge pipe with nitrogen, if gas escapes from the discharge pipe
section of the disconnected compressor, there is a leak from the check valve of discharge pipe (E). Replace the part.
4) With pressure applied to the check joint of discharge pipe with nitrogen, if gas escapes from the oil equalization
pipe section of the disconnected compressor, there is a leak from the oil equalization pipe check valve (F).
Replace the part.
5) With pressure applied to the check joint of discharge pipe with nitrogen, manually open the SV3B valve. If gas
escapes from the suction pipe section of the disconnected compressor, there is a leak from the SV3A valve.
Replace the part.
6) Then manually open the SV3A valve. If gas escapes from the suction pipe section of the disconnected
compressor, there is a leak from the SV3B valve. Replace the part.
7) With pressure applied to the check joint of discharge pipe with nitrogen, manually open the SV3E valve. If gas
does not escape from the suction pipe section of the disconnected compressor, the SV3E valve or oil-return
distributor is clogged. Replace the part.
8) With pressure applied to the check joint of discharge pipe with nitrogen, manually open the SV3D valve. If gas
does not escape from the suction pipe section of the disconnected compressor, the SV3D valve, oil-return
capillary or oil-return distributor is clogged. Replace the part.
M Fan motor
Right-side
Fan
A
PMV1
PMV2
Main heat exchanger
Right-side sub-heat exchanger
Left-side
(TO)
C
B
PMV4
(TE2)
(TE1)
Main heat exchanger
Left-side sub-heat exchanger
Check valve (subheat
exchangers)
Check valve
(main heat
exchangers)
4-way valve
High-pressure sensor
Discharge pipe check joint
(SV6)
SV
(TS1)
D
E
J
SV
(TL)
Fusible
plug
(SV3D)
Oil separator
SV
Oil-return capillary
(SV2)
Low-pressure sensor
Liquid tank
(SV41)
SV
SV
(SV42)
SV
Accumulator
(TD1)
SV
(TD2)
Highpressure
(SV3C)
SW
Highpressure
SW
Highpressure
SW
(SV43)
(TD3)
(TK4)
F
Compressor
1
(Inverter)
Compressor
3
(Inverter)
I
(TK1)
(TK2)
(TK3)
H
SV
(TK5)
(SV3E)
Oil pipe
Liquid pipe check
joint
SV
(SV3F)
G
(SV3A)
SV
Check valve
Oil-return distributor
SV
(SV3B)
Check valve
Liquid-side
service valve
Gas-side
service valve
Balance pipe
packed valve
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