eQuest energy modelling

Last data I obatined in mid-late 2009 shows that eQuest does not support VRV applications yet. These links have some info but calling eQuest direct will get you the best results (provided you can actually get someone who really knows the system).

http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/2009...

http://www.areforum.org/forums/showthread.php?p=929447

There is no straight method to model VRV on eQuest. However, as with many system in eQuest, there are a few possible work arounds.

eQuest 3.63b can model variable speed compressors. By obtaining custom curves from the VRV manufacturer and inputing them in eQuest you could get valid results. This method will work only with Heat Pump type VRVs.

This method is described in more detail at:
http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/2009... It should work fine.

For one recent project, in the SD phase we post processed the results to adjust for VRV, based on a similar project. We modeled a standard Heat Pump system and applied delta savings on the HVAC systems energy use to the results obtained from the simulation. I was able to apply the delta because it was a similar facility and climate. This was only to get initial results, and to get a rough estimate savings - this approach would not be valid for a final LEED submission.

For the final run of the energy model, once the final design documents are out, we intend to model the system by creating custom curves from the manufacturer’s data and following the steps mentioned on the link above.

The other way to simulate VRV would be to extract hourly loads report from eQuest and then do calculations through spreadsheets after obtaining performance data from the manufacturers for the VRV systems.

As I understand it, Energy Pro and Trace are the only software packages that can currently model VRV systems directly. Energy Pro apparently has custom curves for a couple of manufacturers of VRV units.

Energy Plus is also capable of modeling VRV systems accurately. In my opinion is one of the most advanced software currently available, and it is free. Although it is not easy at all to learn to use it. In my company is the one we use.