Fresh Air Unit supply fan power

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Hi, Everyone,

I'm modeling a VRF system with 30% extra fresh air as per ASHRAE standards.
The building has a Fresh Air Unit (without cooling coil and Heat recovery
wheels) which is supplying calculated amount of fresh air to VRF indoor

As the Fresh Air Unit does not have cooling coil and heat recovery wheels,
entire cooling load of fresh air will be taken care by VRF indoor units.

I am doubtful about the Fresh Air Unit supply fan power. How should I model
the fan power of Fresh Air Unit supply fan? Should I break the fan power and
add it with the VRF indoor unit fan power as per the fresh air fraction
provided in that VRF unit?

Thanks in advance!


Anil Jangid

Project Engineer

Aniljangid's picture
Joined: 2014-07-28
Reputation: 0

Adding a Dummy zone you can try by putting it as Unit Ventilator and make the heating source as "not installed". Assign the fan schedule and input Design supply fan in fan power parameters.

Soham Babu | Project Lead


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