Check
SiUS371901EB
427
Part 6 Service Diagnosis
4.6 Refrigerant Shortage Check
In case of
VRV
Systems, the only way to judge as the shortage of refrigerant is with operating
conditions due to the relationship to pressure control and electronic expansion valve control.
As information for making a judgement, refer to the information below.
Diagnosis of shortage of refrigerant
1. The superheating degree of suction gas rises. Consequently, the compressor discharge gas
temperature becomes higher.
2. The superheating degree of suction gas rises. Consequently, the electronic expansion valve
turns open.
3. Low pressure drops to cause the unit not to demonstrate cooling/heating capacity.
CHECK 7
Cooling
High press
u
re
Lo
w
press
u
re
Fre
qu
ency
The opening degree of the indoor
u
nit
electronic expansion
v
al
v
e
b
ecomes
larger.
Either of the electronic expansion
v
al
v
es
b
ecomes f
u
lly open.
Fre
qu
ency comes to the minim
u
m le
v
el.
Fan control is acti
v
ated for high
press
u
re protection
u
nder
cooling control at lo
w
o
u
tdoor
air temperat
u
re, i.e., the fan is
h
u
nting at high press
u
re.
High press
u
re drops
w
ith decrease in
compressor capacity.
If fre
qu
ency comes to the
minim
u
m le
v
el, lo
w
press
u
re cannot
b
e
maintained.
Lo
w
press
u
re rises as the
opening degree of the indoor
u
nit electronic expansion
v
al
v
e
b
ecomes larger.
Fre
qu
ency slightly increases
u
nder the capacity control.
To maintain lo
w
press
u
re,
fre
qu
ency drops
d
u
e to the
capacity control.
Heating
High press
u
re
Lo
w
press
u
re
Fre
qu
ency
The opening degree of the o
u
tdoor
u
nit electronic expansion
v
al
v
e
b
ecomes larger.
The o
u
tdoor
u
nit electronic expansion
v
al
v
e f
u
lly opens and fre
qu
ency increases.
Discharge pipe or lo
w
press
u
re dropping control
(High press
u
re
is maintained at
a constant
le
v
el.)
To maintain lo
w
press
u
re,
fre
qu
ency drops d
u
e to the
capacity control.
Fre
qu
ency drops
d
u
e to the dropping
control.
(Degree of refrigerant shortage)
Higher degree of shortage
Proper amo
u
nt
(Lo
w
press
u
re
is maintained at
a constant
le
v
el.)
Fre
qu
ency comes to
the minim
u
m le
v
el.
Содержание REYQ72-432XAYCU
Страница 1: ...Service Manual Heat Recovery 60 Hz REYQ72 456XATJU A REYQ72 456XAYDU A REYQ72 432XAYCU A SiUS371901EB ...
Страница 92: ...Refrigerant Circuit Piping Diagrams SiUS371901EB 85 Part 2 Refrigerant Circuit BSF6Q54TVJ 3D125655 ...
Страница 93: ...SiUS371901EB Refrigerant Circuit Piping Diagrams Part 2 Refrigerant Circuit 86 BSF8Q54TVJ 3D125656 ...
Страница 455: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 448 REYQ144 168XATJU REYQ144 168XATJA 2D119206B ...
Страница 456: ...Wiring Diagrams SiUS371901EB 449 Part 7 Appendix REYQ72 96 120XAYDU REYQ72 96 120XAYDA 2D119207C ...
Страница 457: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 450 REYQ144 168XAYDU REYQ144 168XAYDA 2D119208C ...
Страница 458: ...Wiring Diagrams SiUS371901EB 451 Part 7 Appendix REYQ72 96 120 144 168XAYCU REYQ72 96 120 144 168XAYCA 2D119209B ...
Страница 459: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 452 1 2 Indoor Unit FXFQ07 09 12 15 18 24 30 36 48TVJU 3D086460B ...
Страница 460: ...Wiring Diagrams SiUS371901EB 453 Part 7 Appendix BYCQ125BGW1 Self Cleaning Decoration Panel for FXFQ TVJU 3D076375A ...
Страница 461: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 454 FXZQ05 07 09 12 15 18TAVJU 3D110443A ...
Страница 463: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 456 FXEQ07 09 12 15 18 24PVJU 3D098557A ...
Страница 464: ...Wiring Diagrams SiUS371901EB 457 Part 7 Appendix FXDQ07 09 12 18 24MVJU C 3D050501C ...
Страница 465: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 458 FXSQ05 07 09 12 15 18 24 30 36 48 54TAVJU C 3D110467C ...
Страница 466: ...Wiring Diagrams SiUS371901EB 459 Part 7 Appendix FXMQ07 09 12 15 18 24 30 36 48 54PBVJU 3D093209B ...
Страница 468: ...Wiring Diagrams SiUS371901EB 461 Part 7 Appendix FXHQ12 24 36MVJU 3D048116C ...
Страница 469: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 462 FXAQ07 09 12 18 24PVJU 3D075354F ...
Страница 475: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 468 VAM1200GVJU 3D073270D ...
Страница 477: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 470 1 4 2 Multi Branch Selector Unit Standard Series BS4Q54TVJ 3D089123B ...
Страница 478: ...Wiring Diagrams SiUS371901EB 471 Part 7 Appendix BS6 8Q54TVJ 2D089122B ...
Страница 479: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 472 BS10 12Q54TVJ 2D089121B ...
Страница 480: ...Wiring Diagrams SiUS371901EB 473 Part 7 Appendix 1 4 3 Multi Branch Selector Unit Flex Series BSF4Q54TVJ 3D123904A ...
Страница 481: ...SiUS371901EB Wiring Diagrams Part 7 Appendix 474 BSF6 8Q54TVJ 2D123905A ...