The VE has reported the wrong ASHRAE Climate Zone for the location of my project.

For some locations the wrong ASHRAE 90.1 Climate Zone will be used and reported, this is not an issue in VE but rather is due to inadequacies in the ASHRAE logic used to devise climate zone.

Notes

VE calculates the actual climate zone for the weather file selected strictly using ASHRAE and KG rules / logic. As NREL (or privately sourced) weather files vary from the original data used to create the ASHRAE appendix B users will find in some instances a variance in the climate zone reported to that expected from ASHRAE appendix B. This is a consequence of the data and not the VE; users should possibly consider alternative weather data files if this issue arises.
IES also recommend reporting the fact (file) to ASHRAE so this can be improved in future.
Typical weather files used for modelling, are also updated by NREL on a periodic basis (e.g. TMY3), so users may find that newer datasets at a location may also vary with earlier datasets (e.g. TMY2).
ASHRAE 90.1 climate classification logic appears in some instances to throw up odd results – this is an ASHRAE standard issue not a VE problem. Known problems:

Locations outside of the USA – New Zealand, parts of India, parts of Europe are known to give incorrect results. When working with 90.1 app B outside of the USA check KG climate classification also as this method logic is known to work correctly. The VE includes some error trapping logic where we have already identified an ASHRAE logic problem, but this does not mean it will pick up all issues.
For the purposes of 90.1 construction standards etc the VE PRM Navigator uses the location defined in ApLocate to set ASHRAE Climate Zone. When location is set the VE uses a climate code / location look-up table to set the climate zone, in this case it is displayed on ApLocate as shown.

Thus even if the selected weather file exhibits a variant climate class the PRM baseline models will be as expected by ASHRAE 90.1.

In cases where the Climate Zone cannot be set this way then “derived” is displayed and it is calculated following the ASHRAE logic.

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