Daikin VRV RXYQ72-384XAYCA, Service Manual

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SiUS342004EB Basic Control
Part 4 Functions and Control 88
5.2 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.
On multi-outdoor-unit systems, this control is made according to values of the first-priority unit,
which is detected with the pressure sensor.
Cooling
Te setting
 1. Min.: 6°C (42.8°F), max.: 17°C (62.6°F)
Heating
Tc setting
 1. Min.: 38°C (100.4°F), max.: 46°C (114.8°F)
Controls compressor capacity to adjust
Te to achieve target value (TeS).
Te set value (Make this setting while in
Setting mode 2.)
Ta(C):
Ta(F):
Te:
TeS:
Outdoor air temperature in Celsius (°C)
Outdoor air temperature in Fahrenheit (°F)
Low pressure equivalent saturation
temperature
Target temperature of Te
(Varies depending on Te setting,
operating frequency, etc.
L M H
A (

1)
(factory setting)
3°C
(37.4°F)
6°C
(42.8°F)
7°C
(44.6°F)
8°C
(46.4°F)
9°C
(48.2°F)
10°C
(50°F)
11°C
(51.8°F)
28.75 – Ta(C) × 0.65 (°C)
(104.55 – Ta(F) × 0.65 (°F))
Controls compressor capacity to adjust
Tc to achieve target value (TcS).
Tc set value (Make this setting while in
Setting mode 2.)
Ta(C):
Ta(F):
Tc:
TcS:
Outdoor air temperature in Celsius (°C)
Outdoor air temperature in Fahrenheit (°F)
High pressure equivalent saturation
temperature
Target temperature of Tc
(Varies depending on Tc setting, operating
frequency, etc.)
L M H
A (  1)
(factory setting)
41°C
(105.8°F)
42°C
(107.6°F)
43°C
(109.4°F)
44°C
(111.2°F)
45°C
(113.0°F)
46°C
(114.8°F)
48°C
(118.4°F)
48 – Ta(C) (°C)
(150.4 – Ta(F) (°F))