DX Kit for connecting AHU to VRF


DX Kit for connecting AHU to VRF

Hitachi DX-Kit (Direct Expansion Kit) seamlessly connects Hitachi VRF equipment with third-party direct heat exchangers, such as air handling units (AHU) or air curtain equipment. Thanks to its various flexible benefits, it is suitable for different applications such as schools with gymnasiums, hotels, or factories. The kit consists of a control box and an expansion valve box.

Hitachi DX-Kit: Versatile AHU Connection

The Hitachi DX-Kit for general AHU connection is highly versatile. It has a capacity range of 2HP to 30HP, with six different models available to meet your specific needs. The DX-Kit provides a flexible connection between Hitachi VRF equipment and your AHU, and offers several connection patterns:

  • 1 VRF ODU to 1 AHU: 50% < Connection Ratio against ODU ≤ 100%

  • 1 VRF ODU to 1 AHU (Separate Type Heat Exchanger): 50% < Connection Ratio against ODU ≤ 100% (Maximum number of DX-kit connections = 5)

  • 1 VRF ODU to Multiple AHUs: 50% < Connection Ratio against ODU ≤ 100% (Different capacity AHUs can be connected)

  • 1 VRF ODU to Multiple AHU/IDU: Connection Ratio against ODU ≤ 110%


Precise temperature control

The combination of the DX-KIT with Hitachi VRF ODU ensures the highest level of precision in maintaining the desired temperature. It offers three types of AHU temperature control:

  • Inlet air temperature control

  • Outlet air temperature control

  • Duty control

All three types of control can be chosen from two methods: capacity control or thermo-off control. Four different sensors (outlet air, inlet air, liquid piping, and gas piping) are included as standard accessories.


Our direct expansion kit makes AC installation more flexible

Hitachi considered all the details to guarantee an easier and more flexible installation with the DX kit.

  • It has an IP54 enclosure rating for the expansion valve box.

  • The maximum total piping length can be up to 1000m.

  • The height difference between the HVAC outdoor unit and AHU can be up to 50m.

  • The thermistor length can be up to 10m.

  • Plus, you can control and monitor it without needing to move from where you are using Hitachi's centralised controller, CSNET Manager, which is available through H-LINK connection.


Manuals, brochures and other product literature. If you need any more information, please get in touch.