IES-VE User Forum

General question about Multiplexing

If I have one large space which is served by FCU's and no other systems, do I need to use multplexing? In real terms this space may have 20 plus FCU's, but will IES make allowances in the energy use depending on the amount of FCU I assign to the zone? i.e will it make a difference.

This depends on the purposes of your model and the specifics of your building. You could simplify it to one large space which is served by one single very large FCU, or you could split it up for one section of space per FCU or anything in between. This is exactly the same as a typical VAV system on an open floor plate or something like that. It's important to understand what will be impacting the space, and if the FCUs will be controlled in unison or allowed to operate independently. If the former, then just keep it as one big space. If the latter, then you should at least zone your space based on what might effect the operation (core perimeter zoning, types of occupancy, etc)