We have a Walmart I work at on occasion. High ceilings, only thing HVAC pushes around is the air for the coolers (I assume) because during Winter it's like a fucking icebox in there, during summer is great, but no heating what so ever, and no amount of bodies in there seems to warm it up. I was in there yesterday, 51°f outside with overcast skies/rain showers and it felt 40ish inside the building. Might be the huge coolers that are wide open and cranked just to above freezing for beer/produce they use but holy hell it's cold in there.