Hello everyone,
I’m currently working on modeling a building with a multiple air loop HVAC system using EnergyPlus. The system consists of two air loops:
Fan Coil Unit (FCU) loop: This loop includes a water coil and a constant fan, supplying conditioned air to the zone.
Outdoor Air Unit (OAU) loop: In this loop, a portion of the return air transfers heat to the outdoor air via a HeatExchanger:AirToAir:SensibleAndLatent before being exhausted. The outdoor air, after passing through the heat exchanger, is then mixed with another stream of return air. This mixed air passes through a water coil before being supplied to the zone.
I’ve encountered difficulties in modeling both air loops to supply to the same zone. I initially tried setting up two Dual Duct Air Loop systems and configuring the fixed portion air terminal, but this hasn’t worked as expected. Additionally, I’ve found that using ZoneHVAC:OutdoorAirUnit and ZoneHVAC:OutdoorAirUnit:EquipmentList doesn’t solve the issue, particularly because the air needs to mix before pass through the water coil and entering the zone.
Has anyone dealt with a similar situation or have any advice on how to model this correctly? I’d greatly appreciate your guidance.
If images would help clarify the setup, please feel free to reach out to me via email at supakit.kumka@kmutt.ac.th. (As a new user, I’m unable to upload images directly.)
Thank you in advance for your assistance!
