air in a can

Mike T., Swampeast MO

Unless you've done a LOT of tightening, your basement in an old house is almost certain to have enough natural infiltration. [At least such is the general guidance in boiler/furnace/water heater installation manuals.]

Commercial-sized exhaust hoods over commercial style ranges can however cause a serious problem in any home.

You can eliminate any possibility by using a boiler that draws its combustion air directly from the outdoors.

Dan_29

air in a can

I was visiting an open house recently and noticed a newer Burnham S-2 FHW boiler installed in the basement.

It had a strange looking contraption next to the burner area on the floor. It was my first view of "air in a can" makeup air for the gas burner system. It is literally, a four inch ductwork connected to what looks like a large old milk can with a fan in it that is wired to the boiler and comes on when the burner is running.

I went home and noticed that my home's prior owner had installed his own "handyman" "make up air"--a four inch insulated dryer-type hose starting in a hole midway up the boiler room wall and vented on the outside wall of the basement(no can or fan involved).

I can see where make up air would be helpful in a very tight new construction house, but is it necessary in an old victorian house,like mine,with a semi-leaky basement?
It seems, in my area (Boston) that city plumbing/heating inspectors and pro installers are insisting or recommending "make up air" in many houses -even old houses with drafty basements. Is this excessive state regulation and a way to increase profit margins on the part of installers? Finally, is my "handyman" vented ductwork in my boiler room a useful or useless attempt at non-forced makeup air?

Dan