Troubleshooting (OP: Unified ON/OFF Controller)
Si37-701
356
Troubleshooting
[Check 11] Check for overcharge of refrigerant.
In case of VRV Systems, the only way to judge as the overcharge of refrigerant is with operating
conditions due to the relationship to pressure control and electronic expansion valve control.
As information for making a judgment, refer to information provided below.
Diagnosis of overcharge of refrigerant
1. High pressure rises. Consequently, overload control is exercised to cause scant cooling
capacity.
2. The superheated degree of suction gas lowers (or the wet operation is performed).
Consequently, the compressor becomes lower in discharge pipe temperature despite of
pressure loads.
3. The supercooled degree of condensate rises. Consequently, in heating operation, the
temperature of outlet air passing through the supercooled section becomes lower.
Cooling
High pressure
Low pressure
Frequency
High-pressure
drooping control
(LP is maintained
at a constant level.)
To maintain LP, frequency
increases under the capacity
control.
HP gradually rises
with increase in
frequency.
Frequency comes to
the minimum level.
Supercooled degree
becomes higher.
(Liquid connection
pipe temperature
lowers.)
LP rises due to
reduced compressor
output.
High pressure
Low pressure
Frequency
Heating
The outdoor unit motorized valve is
closed due to the overload control.
Frequency comes to
the minimum level.
(HP is maintained
at a constant level.)
LP rises due to
reduced frequency.
To maintain HP, frequency reduces
under the capacity control.
HP drops or rises immediately
after the overload control is
complete.
LP drops due to closed
outdoor unit motorized
valve.
Hot gas bypass is activated
for LP protection, i.e.,
hunting at LP.
Higher degree of overcharge
(Degree of overcharge)
Proper quantity
Summary of Contents for VRV III REYQ10PY1
Page 1: ...REYQ8 48PY1 R 410A Heat Recovery 50Hz Si37 701 ...
Page 59: ...Specifications Si37 701 48 Specifications ...
Page 105: ...Refrigerant Flow for Each Operation Mode Si37 701 94 Refrigerant Circuit ...
Page 230: ...Si37 701 Troubleshooting by Remote Controller Troubleshooting 219 ...
Page 374: ...Si37 701 Piping Diagrams Appendix 363 REYQ14P 16PY1 3D058153A S2NPL S1NPH ...
Page 375: ...Piping Diagrams Si37 701 364 Appendix REMQ8PY1 3D057743 ...
Page 376: ...Si37 701 Piping Diagrams Appendix 365 REMQ10PY1 12PY1 3D057742 ...
Page 377: ...Piping Diagrams Si37 701 366 Appendix REMQ14PY1 16PY1 3D057741 ...
Page 382: ...Si37 701 Piping Diagrams Appendix 371 1 3 BS Unit 4D057985A ...
Page 384: ...Si37 701 Wiring Diagrams for Reference Appendix 373 REYQ14 16PY1 3D056774C ...
Page 385: ...Wiring Diagrams for Reference Si37 701 374 Appendix REMQ8PY1 3D055307E ...
Page 386: ...Si37 701 Wiring Diagrams for Reference Appendix 375 REMQ10 12PY1 3D055308E ...
Page 387: ...Wiring Diagrams for Reference Si37 701 376 Appendix REMQ14P 16PY1 3D055309E ...
Page 392: ...Si37 701 Wiring Diagrams for Reference Appendix 381 FXCQ40M 50M 80M 125MVE 3D039557A ...
Page 394: ...Si37 701 Wiring Diagrams for Reference Appendix 383 FXZQ20M 25M 32M 40M 50M8V1B 3D038359 ...
Page 395: ...Wiring Diagrams for Reference Si37 701 384 Appendix FXKQ25MA 32MA 40MA 63MAVE 3D039564C ...
Page 399: ...Wiring Diagrams for Reference Si37 701 388 Appendix FXDYQ180M 200M 250MV1 ...
Page 402: ...Si37 701 Wiring Diagrams for Reference Appendix 391 FXMQ200MA 250MAVE 3D039621B ...
Page 403: ...Wiring Diagrams for Reference Si37 701 392 Appendix FXHQ32MA 63MA 100MAVE 3D039801D ...
Page 406: ...Si37 701 Wiring Diagrams for Reference Appendix 395 2 4 BS Unit 3D055928C ...
Page 423: ...Piping Installation Point Si37 701 412 Appendix ...
Page 427: ...Example of Connection R 410A Type Si37 701 416 Appendix ...
Page 433: ...Method of Checking the Inverter s Power Transistors and Diode Modules Si37 701 422 Appendix ...
Page 447: ...Si37 701 iv Index ...
