Hello,

I have a project that is classified as low-rise residential. It will use a 2-pipe fan coil system and will get its ventilation from operable windows. Does anyone have suggestions on how to model this? I tried to use the Natural ventilation tab but it does not activate for fan coil units and I do not know how to get natural ventilation and a chilled water system to work together.

I am assuming that when it comes to cooling and heating that I just put the OA requirement for the room in the system and it will be the same thing as getting it through the window. Correct? However I do not know how to account for someone opening the window to supplement the cooling and heating. Should I model an air-side economizer and just let that take care of any "free-cooling"? Does anyone have any suggestions or tips?

Thank you for any help.

John Grando LEED AP