Our house is relatively tight, so much so that when we added insulation (and did some sealing in the attic) we had to add an HRV to ensure enough fresh air in the house...
The gas boiler is in a utility room in the basement. The rest of the basement is finished.
With the house so tight, I'm wondering if I need to provide outside air for the gas boiler.
If I remember correctly, when the house was evaluated, the boiler had acceptable exhaust flow (unlike the gas hot water heater that was sized too large for the installation and was exhausting into the utility room rather than into its horizontal exhaust flu). Yea, it was trying to kill us...but that's an old thread...and we're still here. It's not.
One interesting tidbit...we haven't installed our wood stove insert in the first floor fireplace yet (long story) and when I start a fire in the fireplace, smoke makes its way to the basement and things get smoky. I suspect it's being pulled through the ashbox into the utility room, which is directly below the fireplace. If I run the boiler (by turning up a thermostat) the smoke eventually clears...
I'm not sure that this smoke issue is related...but it's possible. The boiler is 26 years old and has a vent damper that closes when the boiler is not running.
I'm thinking that I need to provide additional air for the gas boiler. It's a conventional unit (not gas condensing).
I've done some research, and it looks like the simplest approach is to run some 4" PVC pipe through the utility room wall to the outside. On the outside, I'd run a 90 degree elbow with a short run of PVC down the wall. Inside, I'd run another 90 elbow and PVC down the wall into a trashcan on the floor. Evidently, the trashcan creates a thermal break, keeping cold air from coming in unless the boiler is demanding air.
Or...I could tap into the exhaust of the HRV, grabbing some of that semi treated air and keeping it in the house, effectively pressurizing the utility room. The drawback of this approach is that the utility room is not sealed from the rest of the house, nor will I be able to seal it. Not sure that's an issue...but it's a consideration.
Would appreciate your thoughts....
Thanks!
The gas boiler is in a utility room in the basement. The rest of the basement is finished.
With the house so tight, I'm wondering if I need to provide outside air for the gas boiler.
If I remember correctly, when the house was evaluated, the boiler had acceptable exhaust flow (unlike the gas hot water heater that was sized too large for the installation and was exhausting into the utility room rather than into its horizontal exhaust flu). Yea, it was trying to kill us...but that's an old thread...and we're still here. It's not.
One interesting tidbit...we haven't installed our wood stove insert in the first floor fireplace yet (long story) and when I start a fire in the fireplace, smoke makes its way to the basement and things get smoky. I suspect it's being pulled through the ashbox into the utility room, which is directly below the fireplace. If I run the boiler (by turning up a thermostat) the smoke eventually clears...
I'm not sure that this smoke issue is related...but it's possible. The boiler is 26 years old and has a vent damper that closes when the boiler is not running.
I'm thinking that I need to provide additional air for the gas boiler. It's a conventional unit (not gas condensing).
I've done some research, and it looks like the simplest approach is to run some 4" PVC pipe through the utility room wall to the outside. On the outside, I'd run a 90 degree elbow with a short run of PVC down the wall. Inside, I'd run another 90 elbow and PVC down the wall into a trashcan on the floor. Evidently, the trashcan creates a thermal break, keeping cold air from coming in unless the boiler is demanding air.
Or...I could tap into the exhaust of the HRV, grabbing some of that semi treated air and keeping it in the house, effectively pressurizing the utility room. The drawback of this approach is that the utility room is not sealed from the rest of the house, nor will I be able to seal it. Not sure that's an issue...but it's a consideration.
Would appreciate your thoughts....
Thanks!
