Light in the Dark
Feeling the Heat
Hook up an OAK and be done with it. It will basically bypass your pressure issues, without having to spend an arm and a leg.
Negative Pressure in House, esp. Basement
- Thread starter velvetfoot
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
- Status
I'll stir the pot.
--Seems like you can disable the radon fan temporarily and see if it changes the backdraft rate. Flip the breaker if hardwired.
--Cracking a basement window should decrease the backdraft (as a test). While the stack effect pressure is still present (your upstairs are a few Pascals higher pressure than the basement) opening the window lowers the point which is in balance with the outdoors (the neutral pressure plane, NPP) to be close to the window.
--Solution: figure out a way to heat the oil chimney 24-7 with a small heater (i.e. a draft inducer). Try an incandescent light bulb on a dimmer, tied to the metal flue, and wrapped with non-combustible insulation, so that the wires and dimmer are outside the wrapping. Or you could get a heat tape or coil that can take the heat when the boiler does operate.....
likely the 10-20W required would cost less than the open window, and prevent cold air intrusion...potentially saving energy net.
--Seems like you can disable the radon fan temporarily and see if it changes the backdraft rate. Flip the breaker if hardwired.
--Cracking a basement window should decrease the backdraft (as a test). While the stack effect pressure is still present (your upstairs are a few Pascals higher pressure than the basement) opening the window lowers the point which is in balance with the outdoors (the neutral pressure plane, NPP) to be close to the window.
--Solution: figure out a way to heat the oil chimney 24-7 with a small heater (i.e. a draft inducer). Try an incandescent light bulb on a dimmer, tied to the metal flue, and wrapped with non-combustible insulation, so that the wires and dimmer are outside the wrapping. Or you could get a heat tape or coil that can take the heat when the boiler does operate.....
likely the 10-20W required would cost less than the open window, and prevent cold air intrusion...potentially saving energy net.
suprz, you're not rambling, that's exactly what seems to be happening., plus I had a surprise this morning!
There used to be more air coming through that weighted damper but I put a motor operated Field Controls flue damper in there; still some smokey smell though, when window's closed.
Overnight I left the basement window open about and, for good meeasure, the window next to the stove a half inch or so. Air is streaming through both windows this morning. There doesn't seem to be much of a smokey odor in the basement at all.
And....here's the surprise: the second floor was almost the same temperature as the first floor! I don't know which window opening is contributing most to this effect, but I guess it makes sense. Of course, the basement is cooler.
Or I could just be losing my mind.
I still can't get over the fact of that much air leaving the house, again, with my looking for leaks as well as that blower door test.
There used to be more air coming through that weighted damper but I put a motor operated Field Controls flue damper in there; still some smokey smell though, when window's closed.
Overnight I left the basement window open about and, for good meeasure, the window next to the stove a half inch or so. Air is streaming through both windows this morning. There doesn't seem to be much of a smokey odor in the basement at all.
And....here's the surprise: the second floor was almost the same temperature as the first floor! I don't know which window opening is contributing most to this effect, but I guess it makes sense. Of course, the basement is cooler.
Or I could just be losing my mind.
I still can't get over the fact of that much air leaving the house, again, with my looking for leaks as well as that blower door test.
Yeah, I was also thinking of stuff like blowing the radon exhaust out the oil stack; if I tie it in before the burner, maybe it would supercharge my oil heat? 
Of course, if I changed my backup to propane I would get an efficient condensing boiler with no barometric stuff to fool with. A little expensive for just replacing one backup source with another.
Of course, if I changed my backup to propane I would get an efficient condensing boiler with no barometric stuff to fool with. A little expensive for just replacing one backup source with another.
I have found that while its very easy to find inlet leaks on the lower half of the house, using an incense stick, or just by feeling for drafts, but much more difficult to find the air leaks upstairs. There is no draft of cold air, and the incense stick doesn't show it either. If anyone knows of an effective leak detection method for upstairs (apart from IR camera) I'd love to know.
I suspect your blower door test was rated "good" in the sense that you didn't have serious leaks, or that it was typical for the construction type, but unless they recommended an HRV at that time, you shouldn't assume your house is tight.
Strange things can happen when you open windows,when my stove is going good, sometimes it gets too hot in the stove room, so I open a window, obviously it cools the stove room, but it increases the upstairs temperature, presumably because there is a greater volume of air moving upstairs.
TE
I suspect your blower door test was rated "good" in the sense that you didn't have serious leaks, or that it was typical for the construction type, but unless they recommended an HRV at that time, you shouldn't assume your house is tight.
Strange things can happen when you open windows,when my stove is going good, sometimes it gets too hot in the stove room, so I open a window, obviously it cools the stove room, but it increases the upstairs temperature, presumably because there is a greater volume of air moving upstairs.
TE
jatoxico
Minister of Fire
Have you tried turning the boiler on to warm the flue and see if that helps? I leave my boiler on in the summer even though we don't need it for hot water but I set the temps low (100-120). Hardly uses any oil but runs a little. If you did the same now maybe the warm flue would not suck air down so easy and I doubt you would use much oil at all. I always think it good to exercise the system anyway.
Yes TE, I'd also like to know a way of finding outgoing air leaks. The Hampton manual says to crack open a nearby window when burning, so I guess it's done a lot. This whole thing of opening windows, cutting holes in walls, running the oil burner, etc, just cuts across my grain.
![[Hearth.com] Negative Pressure in House, esp. Basement](/talk/data/attachments/85/85158-27540cdf65d93df74182534eb868dabb.jpg?hash=SBPUJ6WpKa)
I don't see anything too technically challenging there, especially if the boiler stack can be reduced by one length and still be above the cap.
Back to negative pressure. Does the house have a lot of recessed lighting fixtures? If yes, are they sealed?
That could give me hope. I imagine, however, that the height difference was intentional and for some reason. However, if the oil chimney could be easily reduced so that it is below the wood chimney, then maybe it will do the trick. I guess I should consult a chimney sweep.
There is 1 total recessed fixture that I sealed. I also caulked the electrical boxes on the ceiling as well.I will also try to see if there is any leakage thru the walls that terminate at the ceiling, without going into the attic.
There is 1 total recessed fixture that I sealed. I also caulked the electrical boxes on the ceiling as well.I will also try to see if there is any leakage thru the walls that terminate at the ceiling, without going into the attic.
I had to create an air leak into my house because it was too tight. If the dryer was running, or bath fans, opening the front door would cause it to about hit you in the face and it was hard to close it.
Wasn't so much a problem before I had the stove, but after I had to leave a window cracked open or it would pull smoke from the stove into the house. Stove and chimney pipes aren't exactly "air tight" This was even with an OAK.
Anyhow what I did was drill holes in the top plate of one of the interior walls and ran 3 2" pipes through and into the attic. Put a "U" and bit of pipe going down to make an air damn.
In the stud bay at the bottom I have a grille/vent.
HRV would be a better solution, but I wasn't going to drop $4-5000 for one installed. I'll just use a bit more firewood.
Wasn't so much a problem before I had the stove, but after I had to leave a window cracked open or it would pull smoke from the stove into the house. Stove and chimney pipes aren't exactly "air tight" This was even with an OAK.
Anyhow what I did was drill holes in the top plate of one of the interior walls and ran 3 2" pipes through and into the attic. Put a "U" and bit of pipe going down to make an air damn.
In the stud bay at the bottom I have a grille/vent.
HRV would be a better solution, but I wasn't going to drop $4-5000 for one installed. I'll just use a bit more firewood.
Would one of these (broken link removed to http://www.blackanddecker.com/power-tools/TLD100.aspx) help you?
(broken image removed)
![[Hearth.com] Negative Pressure in House, esp. Basement](https://www.hearth.com/talk/data/attachments/85/85250-ebeb5223cec371a3e3a97be02abbe144.jpg?hash=6R5XdlFWjx "[Hearth.com] Negative Pressure in House, esp. Basement")
That may be the very model I have! Upstairs leaks do not let cold air in, they let warm air out, so there is no cold spot to find. Those detectors are great downstairs, and good at finding areas where insulation is a problem too. Luckily there are not so many potential places for air leaks upstairs.
TE
- Status
Similar threads
