As I sit here in New England’s version of the frozen tundra, I watch as people everywhere scramble to seal up every tiny draft and pinhole they can find as the temperature once again drops below the nothing mark. But while this is an acceptable, if not neurotic, pastime for the vast and chilly civilians, we, as professionals, need to chase and protect a different draft; combustion air.

Rarely do we find one of our new colleagues, nor a homeowner for that matter, that instinctively understands that air that exits in the house/building/teepee by way of a chimney must be replaced, or “made up” by air entering somewhere else, hence, “make up air”. Ahhh, fate is giggling at us again as these two pursuits have a propensity to spar with one another. Please allow me to elaborate on the obvious.

A heating tech is called into a local franchise restaurant because both of the water heaters on site refused to do their jobs. The tech arrived, looked at few possible culprits, then tested the gas pressure but found nothing obvious wrong. Both units would run for a couple of minutes, and then begin to run poorly. Next the puzzled tech changed a gas valve (Huh? Both units were doing the same thing!). After two wasted hours, the service man called in his boss to help.

When the boss arrived, one of the restaurant workers led him back to the mechanical room, pushed open the heavy door, and let it swish closed behind them. As the first man explained to the boss what the problem was, the young kid from the kitchen listened as if he might be able to help. As the diagnosis continued in silence, the kid blurted out how cold it was in the room this morning. Then he found an open vent or something in the wall over there, so he stuffed an old blanket in it to stop the breeze. Flash! Local commerce, cutting edge combustion technology, and experienced HVAC technicians foiled by cold kid with a blanket.