OJ Air2 Master Module

OJ Air2 Master Module OJ Electronics is a global supplier of thermostats, power controls, HVAC supplies and much more


The intelligent HVAC controller with RS485 Modbus communication

OJ Air2 Master is a custom made and flexible controller, specifically designed for ventilation systems. It has a built-in web server with intelligent interface and a simple and attractive user interface, which allows optimal energy consumption control. OJ Air2 Master is financially attractive in association with complex ventilation units. It is a simple and reliable automation unit, which has been developed based on specialised technical competence and application knowledge.

  • Specifically designed for ventilation systems
  • Built-in web server with simple and intelligent interface
  • Simple and reliable
  • How to connect a 9-pol sub-D connector to the RJ14 in the OJ Air2 system?


  • Which pin is A and B in an RJ14 plug?


  • Why do I get these warnings?



    • Check Max. air volume (could be set to low)
    • Check fan speed. If fan speed is 100% - check max fan speed.


  • How to connect two 24VAC transformers with an OJ Air2 Master?


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  • How to setup the OJ Air2 to send e-mail notification in caseo of Error?


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  • How to cure Alarm 71 and Alarm 73 on the OJ Air2 controller?



    • Check rotation direction of fan
    • Check max Hz
    • Check max motor current
    • Check v/f characteristics
    • Check filter pressure
    • Check damper position



  • OJ Air2 alarmlist

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Optimised for efficient performance

Enhanced AHU control, optimised temperature, air and water flow give energy savings of up to 65%.


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