<
MMY-MUP2201*, 2401*
>
Check items and procedures to follow when checking oil circuit with compressor(s) disconnected
Procedure
Location
Check item
Leakage of outdoor PMV
Leakage of check valve in
discharge pipe convergent
section
A,B
C,D
1) With PMV 1, 2, 3 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 (A), 2 (B) or 3 (C)
and check valve of discharge pipe (D). Replace the troubled parts.
2) If the pressure does not increase, fully open outdoor PMV1 and 3 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.
Clogging of SV3D valve
Clogging of oil-return capillary
Clogging of oil-return distributor
F
4) 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.
Leakage of check valve in
discharge pipe
E
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.
TS1
TS3
Low-pressure
sensor
M
Fan
Fan motor
4-way valve
Oil s
eparat
or
㪦㫌㫋㪻㫆㫆㫉㩷㪬㫅㫀㫋㩷㩿㪉㪉㪃
㪉㪋㪟㪧㪀
㪤㫆㪻㪼㫃㪑㩷
MMY-MUP2201*, 2401*
SV
SV3D
TL1
High-pressure
sensor
A
l t
M
Fan
Fan motor
TO
PMV1
TG3
TG1
PMV2
TG2
PMV3
TL2
TE1
Left side
Main heat exchanger
TE2
Left side
Sub heat exchanger
Right side
Main heat exchanger
TE3
Right side
Sub heat exchanger
In
v
e
rte
r h
e
a
t
s
ink
䌄
㪝
㪘
㪙
㪚
TD2
TK2
TK1)
(TD1)
SV
SV
TL3
Liquid side
Service valve
Gas side
Service valve
Subcool
Heat Exchanger
PMV4
C
o
m
p
re
sso
r 2
(I
n
v
erter)
Co
m
p
re
s
s
o
r 1
(I
n
v
erter)
SV41
High-
pressure
switch
High-
pressure
switch
SV42
SV
SV3F
Accumulator
SV
Symbol
㪜
㪜
SV
Solenoid
valve
Capillary
tube
Check
valve
Check
joint
Strainer
Temperature
sensor
Distributor
- 270 -
Summary of Contents for MMY-MUP0801HT7JP
Page 309: ......
