Hi @MichaelDonn,
As I said on the other thread - I think the air side economiser is causing the mechanical ventilation to appear.
On the storage side of things, it’s a question I’m interested in learning more about. Looking at the code, the HB definition of “Storage” is just the remaining aspect of the energy balance to make it equal to 0 as a whole once all the other factors HB does factor in have been accounted for.
I feel like there might be potential with Storage being treated as a catch all by HB for aspects of the energy balance to be missed (a variable in E+ that isn’t being included in the other data?).
Up to now I’ve thought about Storage as thermal mass, generally where solar enters the room as a gain, but is mostly absorbed by surfaces rather than directly contributing to instantaneous air temperature increase in the space. I believe this is generally true, but always interested in learning more.
I asked a question on the topic here that Chris replied to