Compressor Pi Control - Daikin RQYQ140-180PY1 Service Manual

SiBE341001

2.5.2 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.
[Cooling operation]
Controls compressor capacity to adjust Te to achieve target value (TeS).
Te set value (Make this setting while in Setting mode 2.)
Te setting
L M (Normal)
(factory setting)
3ºC 6ºC
Te : Low pressure equivalent saturation temperature (°C)
TeS : Target temperature of Te (Varies depending on Te setting, operating frequency, etc.)
* On multi-outdoor-unit systems, this control is made according to values of the first-priority unit, which is detected with
the pressure sensor.
[Heating operation]
Controls compressor capacity to adjust Tc to achieve target value (TcS).
Tc set value (Make this setting while in Setting mode 2.)
Tc setting
L M (Normal)
(factory setting)
43ºC 46ºC
Tc : High pressure equivalent saturation temperature (°C)
TcS : Target temperature of Tc (Varies depending on Tc setting, operating frequency, etc.)
* On multi-outdoor-unit systems, this control is made according to values of the first-priority unit, which is detected with
the pressure sensor.
Function
H
7ºC 8ºC 9ºC
H
47ºC
Detailed Control Functions
10ºC 11ºC
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