Daikin VRVIII-S, Service Manual

Page: 53 / 266

Basic Control SiENBE34-703
42 Function
2.2 Compressor PI Control
Compressor PI Control
Carries out the compressor capacity PI control to maintain Te at constant during cooling
operation and Tc at constant during heating operation to ensure stable unit performance.
[Cooling operation]
[Heating operation]
RX(Y)MQ4 · 5 · 6P
Controls compressor capacity to adjust Te to
achieve target value (TeS).
Te : Low pressure equivalent saturation temperature
(°C)
Te setting (Set in Set-up mode 2) TeS : Target Te value
(Varies depending on Te setting, operating
frequency, etc.)
L M (Normal)
(factory
setting)
H
3 6 9
Controls compressor capacity to adjust Tc to
achieve target value (TcS).
Tc : High pressure equivalent saturation temperature
(°C)
Tc setting TcS : Target Tc value
(Varies depending on Tc setting, operating
frequency, etc.)
L M (Normal)
(factory
setting)
H
43 46 49
STn INV(Fullload) INV(Unload) STn INV(Fullload) INV(Unload) STn INV(Fullload) INV(Unload)
1 36.0Hz 11 80.0Hz 21 140.0Hz
2 39.0Hz 12 86.0Hz 22 146.0Hz
3 43.0Hz 13 92.0Hz 23 152.0Hz
4 47.0Hz 14 98.0Hz 24 158.0Hz
5 52.0Hz 15 104.0Hz 25 164.0Hz
6 52.0Hz 57.0Hz 16 110.0Hz 26 170.0Hz
7 57.0Hz 64.0Hz 17 116.0Hz 27 175.0Hz
8 62.0Hz 71.0Hz 18 122.0Hz 28 180.0Hz
9 68.0Hz 78.0Hz 19 128.0Hz 29 185.0Hz
10 74.0Hz 20 134.0Hz 30 190.0Hz
31 195.0Hz
∗
Compressors may operate in a pattern other than those listed in above tables subject to the operating conditions.
Selection of full load operation to/from unload operation is made with the unload circuit solenoid valve
(Y3S=SVUL). The full load operation is performed with the SVUL set to OFF, while the unload operation is
performed with the SVUL set to ON.