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Central AHU outlet air condition problem

Hi at all! I am working at my master thesis on EnergyPlus, I have to modifying the DOE Large Hotel Post 1980 model in order to test different HVAC system. I am finding some problem during the definition of a central AHU. My idea is to create a central AHU that pre-conditioning the outdoor air (I defined a range of RH and a range of T that have to be respected in some nodes) and then satisfy the remaining loads in the different zones with fan-coils.

I had two problem:

1 - I defined the outdoor air flow rate according to the minimum outdoor air requirement (sum of all zone minimum requirements). I checked the outdoor air flow rate in each zones, it changes according occupation but work only at 0 or 100%. There is a way to regulate the outdoor air flow rate according to the real occupation of a zone?

2 - I checked the RH and the Temperature in the nodes in which I defined the SetpointManager and they are not respected sometimes. What could be the cause?

For defining the AHU I used the following elements: - AirLoopHVAC:UnitarySystem - SizingSystem - Coil:Heating:Water - Coil:Cooling:DX:SingleSpeed - Humidifier:Steam:Gas - SetpointManager:MultiZone:Heating:Average - SetpointManager:MultiZone:Cooling:Average - SetpointManager:MultiZone:MinimumHumidity:Average - SetpointManager:MultiZone:MaximumHumidity:Average

Thank you!

Andrea

Central AHU outlet air condition problem

Hi at all! I am working at my master thesis on EnergyPlus, I have to modifying the DOE Large Hotel Post 1980 model in order to test different HVAC system. I am finding some problem during the definition of a central AHU. My idea is to create a central AHU that pre-conditioning the outdoor air (I defined a range of RH and a range of T that have to be respected in some nodes) and then satisfy the remaining loads in the different zones with fan-coils.

I had two problem:

1 - I defined the outdoor air flow rate according to the minimum outdoor air requirement (sum of all zone minimum requirements). I checked the outdoor air flow rate in each zones, it changes according occupation but work only at 0 or 100%. There is a way to regulate the outdoor air flow rate according to the real occupation of a zone?

2 - I checked the RH and the Temperature in the nodes in which I defined the SetpointManager and they are not respected sometimes. What could be the cause?

For defining the AHU I used the following elements: - AirLoopHVAC:UnitarySystem - SizingSystem - Coil:Heating:Water - Coil:Cooling:DX:SingleSpeed - Humidifier:Steam:Gas - SetpointManager:MultiZone:Heating:Average - SetpointManager:MultiZone:Cooling:Average - SetpointManager:MultiZone:MinimumHumidity:Average - SetpointManager:MultiZone:MaximumHumidity:Average

Thank you!

Andrea