AIRSTAGE VRF Technical Reference

VRF - master Indoor unit

Master Indoor Unit operation and mode selection
For applicable AIRSTAGE J-Series and V-Series reverse cycle VRF heat pump systems.
On these systems, one indoor unit is selected as the Master Indoor Unit. The Master Indoor Unit determines the operating mode for the VRF system. Mode selection must therefore be made from the controller connected to the Master Indoor Unit.

How the system works

  • One indoor unit is selected to determine the system operating mode.
  • To change the operating mode, use the controller for the Master Indoor Unit.
  • When using a controller connected to another indoor unit, the Mode setting is locked and cannot be changed.
  • Settings other than operating mode, such as temperature and fan speed, can still be adjusted independently at the individual indoor unit controllers.
Mode button locked?
This is expected when the controller is not connected to the Master Indoor Unit. To change between Auto, Cool, Dry or Heat, use the Master Indoor Unit controller.

Changing the operation mode

StepAction
1Go to the controller for the Master Indoor Unit.
2Press Mode.
3Select the required mode: Auto, Cool, Dry or Heat.
4The system mode will change and the other indoor units will operate within the mode available for that system condition.
5Adjust temperature, fan speed and other permitted settings at each indoor unit controller as required.

To change the operating mode again later, return to the Master Indoor Unit controller and repeat the process.

Mode compatibility across indoor units

Master Indoor Unit modeOther indoor units
HeatCan operate in Heat or be turned Off.
CoolCan operate in Cool or Dry, or be turned Off.
DryCan operate in Cool or Dry, or be turned Off.
AutoThe Master Indoor Unit determines whether the system operates in heating or cooling, and the other indoor units follow the resulting system mode.
Important: The system operating mode must remain consistent, but individual indoor units can still have their own temperature, fan speed and other available settings.

Record the Master Indoor Unit

For easier future operation, record the location of the Master Indoor Unit and its controller:

Master Indoor Unit location 
Controller location 

Applicable series and models

SeriesOutdoor unit / condenser models
J-II Outdoor UnitsAJYA36LALH, AJYA45LALH, AJYA54LALH
J-IIS Outdoor UnitsAJT040LCLAH, AJT045LCLAH, AJT054LCLAH
J-IVS Outdoor UnitsAJT040LCLBH, AJT045LCLBH, AJT054LCLBH
AJT040LCLCH, AJT045LCLCH, AJT054LCLCH
J-III Outdoor UnitsAJY040LBLAH, AJY045LBLAH, AJY054LBLAH
J-IV Outdoor UnitsAJY040LBLBH, AJY045LBLBH, AJY054LBLBH
AJT040LBLCH, AJT045LBLCH, AJT054LBLCH
J-IIIL CondensersAJY072LELAH, AJY090LELAH, AJY108LELAH
AJY126LELAH, AJY144LELAH
J-IVL CondensersAJY072LELBH, AJY090LELBH, AJY108LELBH
AJY126LELBH, AJY144LELBH
V-II CondensersAJYA72LALH, AJYA90LALH, AJY108LALH
AJY126LALH, AJY144LALH
V-III CondensersAJY072LALBH, AJY090LALBH, AJY108LALBH
AJY126LALBH, AJY144LALBH

Controller instructions

For detailed instructions on the buttons, menus and functions of the installed controller, refer to the Operation Manual supplied with the indoor unit/controller.

AIRSTAGE VRF technical reference  |  Reverse Cycle VRF Heat Pump Mode Control