Are these vents?

What are these? Seen in back of four story old office building. Look like very large vents for some kind of heating system. Can’t go inside yet, reporting to potential buyer who just wants opinion before pursuing this investment purchase.

More on other levels, I think I remember each floor

Suspect cooling tower air transfer .

Def air vents

Commercial buildings are required a minimum of 10% outside air as compared to the CFM output of the air handler. Most would have a 20LB air operated control dampers, that building looks old enough probally everything missing control wise



Make up and exhaust air. Because of sick building syndrome, air exchanges are required in building.

Fresh air intakes. could be a boiler room

Exhaust and supply air vents should not be directly beside each other. Exhaust would be sucked back into the supply.

One of the worst cases of sick building syndrome in my area was in the kitchen of a new hospital: Exhaust air from the dishwasher (quite harsh detergent) was being sucked in by the general ventilation air system for the kitchen. At times, up to 7-8 people fell sick and had to leave the area.

Opps I never even noticed that. It should have read Make up or exhaust air.