Sizing an EnergyPlus plant loop with both heating and cooling coils

asked 2016-05-02 18:35:08 -0500

I'm developing a model of a runaround loop heat recovery system in EnergyPlus. I have a plant loop that has both a cooling coil (cooling the outdoor air stream) and heating coil(dumping heat to exhaust air stream). I'm running into an interesting situation where I want to size the cooling coil with one Sizing:Plant object and the heating coil with another. I can get the coils to autosize using conditions in the middle of each coil (Design Loop Exit Temperature of ~60F), but this tends to undersize each coil. Has anyone successfully autosized both heating objects and cooling objects on a single plant loop?

answered 2016-05-03 12:00:55 -0500

Archmage

7185 ●3 ●11

I am not aware of anyone succeeding at this. My understanding is that EnergyPlus's sizing routines are not really capable of autosizing a run-around loop, neither the plant side nor the air side. I think you would have to hard size each coil at input. As a start you could grab the coil sizing results for the main cooling coil from a previous run (without the run-around loop).