Daikin SkyAir FHQ24PVJU - Compressor PI Control

Basic Control SiUS281811EA
106 Part 4 Functions and Control
2.2 Compressor PI Control
Cooling Operation
Controls compressor capacity to achieve target Te value (TeS).
(1) VRT control (Default)
When the required capacity of all indoor units (suction air temperature – set temperature) is small,
the target evaporation temperature is further increased in order to adjust capacity. From the
outdoor unit side, the temperature difference for all indoor units (ΔT) is confirmed, and the target
temperature is changed.
(2) Constant pressure control
The target evaporation temperature is not changed.
Te setting (Make this setting while in setting mode 2.)
Heating Operation
Controls compressor capacity to achieve target Tc value (TcS).
(1) VRT control (Default)
When the required capacity of all indoor units (set temperature – suction air temperature) is small,
the target condensation temperature is further decreased in order to adjust capacity. From the
outdoor unit side, the temperature difference for all indoor units (ΔT) is confirmed, and the target
temperature is changed.
(2) Constant pressure control
The target condensation temperature is not changed.
Tc setting (Make this setting while in setting mode 2.)
Te:
TeS:
Tc:
TcS:
Low pressure equivalent saturation temperature
Target Te value
(Varies depending on Te setting, operating frequency, etc.)
High pressure equivalent saturation temperature
Target Tc value
(Varies depending on Tc setting, operating frequency, etc.)
Carries out compressor capacity PI control to maintain Te at constant during cooling operation
and Tc at constant during heating operation, thus ensuring stable unit performance.
Lower Normal
VRT
(Default)
Higher
3°C
(37.4°F)
6°C
(42.8°F)
Variable
8°C
(46.4°F)
9°C
(48.2°F)
10°C
(50°F)
11°C
(51.8°F)
VRT
(Default)
Normal Higher
Variable
46°C
(114.8°F)
52°C
(125.6°F)