Daikin VRV EMERION RXYQ-AATJA, Service Manual

Page: 111 / 429

SiUS342303E Basic Control
Part 4 Functions and Control 104
5.2 Compressor PI Control
In order to provide a steady capacity, the compressor capacity is controlled to achieve temperature
Te (or Tc) during cooling (or heating) operation.
During cooling (or heating) operation
The compressor capacity is controlled so Te (or Tc) approaches TeS (or TcS) (target value of
temperature).
1. VRTsmart Control
 When all the connected indoor units are VRTsmart control applicable models
The required capacity is calculated based on the operation condition of each individual indoor unit
and this data is transmitted to the outdoor unit. The outdoor unit adjusts the refrigerant temperature
of the whole system to an adequate value according to the indoor unit that needs the most
capacity.
In case of target evaporation (or condensation) temperature adjustment, first the capacity is
adjusted by changing the indoor unit airflow to L tap. If the capacity is still too much, the target
evaporation (or condensation) temperature is elevated further to adjust.
2. VRT Control
 When one or more of the connected indoor units are not VRTsmart control applicable models
If the required capacity becomes low (or high) in all indoor units (Room temperature Th1 - set
temperature), the target evaporation (or condensation) temperature is elevated further to adjust. In
the outdoor unit, the difference of temperature (
∆ T) in all indoor units is checked and the set
temperature is changed. Unlike VRTsmart control, there is no airflow control of the indoor units.
3. Te fix Control (for cooling)
The target evaporation temperature is not changed.
Te value (Set in mode 2-8)
Te: Low pressure equivalent saturation temperature
TeS: Te target value (varies according to Te setting, compressor operation frequency, etc.)
4. Tc fix Control (for heating)
The target condensation temperature is not changed.
Tc value (Set in mode 2-9)
Tc: High pressure equivalent saturation temperature
TcS: Tc target value (varies according to Tc setting)
Standard
(Factory setting)
High
6°C
(42.8°F)
7°C
(44.6°F)
8°C
(46.4°F)
9°C
(48.2°F)
10°C
(50.0°F)
11°C
(51.8°F)
Low Standard
High
(Factory setting)
41°C
(105.8°F)
43°C
(109.4°F)
46°C
(114.8°F)