Special Control
SiUS34-907
36
Function
3. Special Control
3.1
Startup Control
This control is used to equalize the pressure in the front and back of the compressor prior to the startup of the
compressor, thus reducing startup loads. The inverter is turned ON to charge the capacitor.
In addition, to avoid stresses to the compressor due to oil return or else after the startup, the following control is
made and the position of the four-way valve is also determined. To position the four-way valve, the master and
slave units simultaneously start up.
3.1.1 Startup Control in Cooling Operation
3.1.2 Startup Control in Heating Operation
Thermostat ON
Pressure equalization control
prior to startup
Startup control
STEP 1
STEP 2
Compressor
0 Hz
57 Hz Unload
57 Hz Unload
+2 steps/20 sec.
(until Pc - Pe>43.5 psi is achieved)
Outdoor unit fan
STEP 7
Ta<68
°
F: OFF
Ta
≥
68
°
F: STEP 4
+1 step/15 sec. (when Pc>313 psi)
-1 step/15 sec. (when Pc<257 psi)
Four-way valve (Y1S)
Holds
OFF
OFF
Main electronic expansion
valve (EV1)
0 pls
480 pls
480 pls
Subcooling electronic
expansion valve (EV3)
0 pls
0 pls
0 pls
Hot gas bypass valve
(SVP)
OFF
OFF
OFF
Ending conditions
•
Pc - Pe<43.5 psi
•
A lapse of 1 to 5 min.
A lapse of 10 sec.
•
A lapse of 130 sec.
•
Pc - Pe>56.6 psi
OR
OR
Thermostat ON
Pressure equalization control
prior to startup
Startup control
STEP 1
STEP 2
Compressor
0 Hz
57 Hz Unload
57 Hz Unload
+2 steps/20 sec.
(until Pc - Pe>43.5 psi is achieved)
Outdoor unit fan
From starting
~ 1 min. : STEP 7
1 ~ 3 min. : STEP 3
3 ~ 5 min. : OFF
STEP 8
STEP 8
Four-way valve (Y1S)
Holds
ON
ON
Main electronic expansion
valve (EV1)
0 pls
0 pls
0 pls
Subcooling electronic
expansion valve (EV3)
0 pls
0 pls
0 pls
Hot gas bypass valve
(SVP)
OFF
OFF
OFF
Ending conditions
•
Pc - Pe<43.5 psi
•
A lapse of 1 to 5 min.
A lapse of 10 sec.
•
A lapse of 130 sec.
•
Pc>392 psi
•
Pc - Pe>56.6 psi
OR
OR
Summary of Contents for VRV III-S RXYMQ36 48PVJU
Page 1: ...RXYMQ36 48PVJU R 410A Heat Pump 60Hz SiUS34 907...
Page 9: ...SiUS34 907 Safety Considerations viii...
Page 237: ...Wiring Diagrams SiUS34 907 228 Appendix 2 2 Field Wiring RXYMQ36 48PVJU 3D065370...
Page 238: ...SiUS34 907 Wiring Diagrams Appendix 229 2 3 Indoor Unit FXFQ12M 18M 24M 30M 36MVJU 3D042620C...
Page 239: ...Wiring Diagrams SiUS34 907 230 Appendix FXZQ07M 09M 12M 18MVJU 3D059263...
Page 240: ...SiUS34 907 Wiring Diagrams Appendix 231 FXDQ07M 09M 12M 18M 24MVJU 3D050501A...
Page 241: ...Wiring Diagrams SiUS34 907 232 Appendix FXMQ07P 09P 12P 18P 24P 30P 36P 48PVJU 3D065984A...
Page 242: ...SiUS34 907 Wiring Diagrams Appendix 233 FXHQ12M 24M 36MVJU 3D048116A...
Page 243: ...Wiring Diagrams SiUS34 907 234 Appendix FXAQ07M 09M 12M 18M 24MVJU 3D046039D...
Page 244: ...SiUS34 907 Wiring Diagrams Appendix 235 FXLQ12M 18M 24MVJU FXNQ12M 18M 24MVJU 3D045644A...
Page 247: ...Option List SiUS34 907 238 Appendix...
Page 249: ...Example of Connection 240...
Page 263: ...Precautions for New Refrigerant R 410A SiUS34 907 254 Precautions for New Refrigerant R 410A...