Can a low temperature VAV system be modeled explicitly in any of the energy modeling softwares? The system I am trying to model tempers the SA down to 46F at the AHU cooling coil, then a parallel fan power box (variable speed ECM running continuously when the AHU is on) mixes RA with the low temp SA to about 55F before it is delivered to the space to avoid occupant comfort problems associated with dumping cold air. During cooler months the cooling coil leaving air temp would be reset to 55F in order to reduce the amount of reheat required.
I have spoke with a Trane product support and Trace cannot model the 46F LAT from the coil with 55F SA temp to the space unless I were to add 9F of duct loss, which would negate the whole benefit of using a low temp VAV system. Is it possible to model this in any of the other programs such as eQuest, EnergyPlus or IES?
