Ideas needed to increase draft for Progress Hybrid installation

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WarmInIowa

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Jan 13, 2011
83
Central IA
I'm looking for some ideas to see what I can change or add to increase my draft. I originally installed a Woodstock Fireview 5 years ago. I added the stove to reduce propane useage. This house was built in 2000 with a lot of windows facing the wrong direction. We have 2x6 wall construction with adequate insulation - its just the amount of space we are heating and all of the windows which face N/NW and get a lot of wind in the winter.

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Sometimes I have adequate draft, and other times I have negative draft. I used to warm the chimney regularly with a hair dryer before starting a fire. This was easy with the Fireview but not possible through the Progress Hybrid (PH). I can take the clean out cap off the bottom of the chimney but that is not really a good solution, especially in the middle of winter.

The PH uses a winding path through the stove to maximize the heat transfer from the smoke to the stove and increase efficiency and stove heat output. The design works VERY well and my house is much warmer than it was with the Fireview. However, this winding path is also a restriction, and with a poor draft, it is a problem for this installation. Here are some of the issues:
  • When reloading, if I open the door all the way I usually get smoke spillage. Sometimes from the door, sometimes from the back side of the stove on the opposite end as the reloading door. This can be a lot of smoke on occasions.
  • I get the smoke smell in the house. I did not have this problem with the Fireview and have replaced the door gasket twice with no change.
  • Occasionally have wind problems (causing smoke spillage) which I suspect would be less with a better draft. This is much more likely to happen just after a reload, but on a very windy day, it has happened when the stove is running full out.
The stove was added to the house, and thus has an exterior doulble wall insulated pipe without a chase. I realize going up through the house would have been better, but it was not an option with my better half. Chimney is 27' tall with an exit straight out the back of the stove for 1.5' then up with (1) 30 degree bend. A couple pics are included for more details.

This house due to it's size will not be permanent for us, so I'm not looking to spend a lot of $. One of my thoughts is to add an outside air kit, but I really don't know if this will help or not? Thoughts?
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Seems like I recall you having this problem last winter. It appears the chimney is a good height. An OAK would be a good idea as then it will not be taking air from the house so running dryer or exhaust fans would not bother the draft. A chase might help but I've never thought they helped that much. Perhaps others have had other experience with the chase helping and I'd like to hear if they have. One could also perhaps look at a draft inducer. I've heard and read good things about them but I have no experience with these.

Have you contacted Woodstock to see if they have any suggestions?
 
Suggestion, you could take the 2 30 degree bends out of the chimney to clear the eave. They make a kit to go through the Soffit. I know this ain't ideal, but like backwoods stated, looks plenty tall enough. Maybe a pure straight shot will do the trick. Wish you luck.
 
Let's start with the easy (cheap) stuff first:

Make sure the screen is completely clear of ash, mine clogged once and this can cause MAJOR smoke spillage.
To warm the flue in shoulder season, I use 3-4 crumpled newspapers to get a hot fire going very quickly. I let them burn completely out and then load the stove. I never had to do this with the FIreview, the PH is definitely pickier.
Try opening a nearby window just a crack to see if it helps before installing an OAK.

Exactly when do you get the negative draft problem, during cold startup, during windy conditions, or both? If its during high winds, Dennis is probably right (he has a way of being right sometimes!) and you need some kind of draft inducer.

The fan powered ones are VERY expensive. The non-electric are much cheaper, here is one example: http://www.luxurymetals.com/wind_directional_caps.html

Regarding smoke out the rear of the stove when reloading: I am certain this comes from the air INLET damper. The path is very short from the firebox to this inlet, and marginal flue draft can result in the inlet damper becoming your flue! Air rushes in through the door, and exits at the opposite side of the stove at the far end of the air inlet slot. I had this happen once, and I CLOSED the air flapper (horizontal handle). The smoke spillage stopped. You want to OPEN the draft lever (Vertical) before opening the door to get a good draft going. Once the door is open, if you get smoke out the inlet, try closing the draft until you get the stove loaded and the door shut. I know this sounds crazy, but it worked for me.
 
What kind of cap do you have up there? Try removing it and see if things improve, it could be a little restrictive, might want to try a different style.

I also think an OAK is a good idea as well.
 
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My cap up top is a 6" vacu-Stack which is designed to help stop the wind induced down drafts. It is much better with it on, but I still have occasional problems.

I can not define when I have negative draft. I has happened when cold, very cold, and not too cold. Sometimes when windy and sometimes when no wind. I currently have the smoke smell in the house, I'm guessing due to lower draft with it being a little warmer this afternoon. I did not have this last night or this morning.

I have contacted Woodstock and the last suggestion was to get the chimney cleaned and inspect the cap to verify it isn't "clogged" creating a restriction. I have this schedule for two weeks from now.

My screen is very clean. I have not had any issues with keeping it clean since I've had this stove.

fire-man: I will pay attention to the smoke spillage and try messing with the draft lever.

My next question is if I'm getting smoke spillage in from the air intake during reload, if I had the Outside Air Kit (OAK), wouldn't that seal this area and eliminate this problem? Would adding the outside air kit help the draft, or is that really not its function?

I have tried opening the window right by the stove a little and it may help a little, its hard to say. It definately does not eliminate the negative draft issue when I'm having that problem. It may help, I really can't tell for sure.

Thanks for the suggestions so far. I forgot to mention in my original post, I took a picture of the back yard facing away from the chimney to give a view of what the layout is. As you can see, I have a few tall oak trees about 60' from the house and then it drops off with a steep hill down about 50' to the river below. The wind usually comes from the NW which would be from along or across the river and up the hill. I've often wondered if this is creating some type of problem with the draft. I have no idea, just a thought after reading that trees and tall building can affect draft.
 
Air traveling down the chimney rather than up is a symptom of a house which is at negative air pressure, either due to high exfiltration rates (air is leaving faster than it can come in), or because it is very tight and uses continuously running fans to guarantee adequate fresh air exchange. I have the latter situation, and even with a tall inside chimney, I can get negative draft, particularly when it is warm outside. An outside air kit will fix your problem. It fixed mine.

An aside- have a blower door test done on the house. You might have some pretty serious leaks, which also happen to be the cheapest to fix. Also, make certain your cook stove range hood isn't running when you reload.
 
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My cap up top is a 6" vacu-Stack which is designed to help stop the wind induced down drafts. It is much better with it on, but I still have occasional problems.

I can not define when I have negative draft. I has happened when cold, very cold, and not too cold. Sometimes when windy and sometimes when no wind. I currently have the smoke smell in the house, I'm guessing due to lower draft with it being a little warmer this afternoon. I did not have this last night or this morning.

I have contacted Woodstock and the last suggestion was to get the chimney cleaned and inspect the cap to verify it isn't "clogged" creating a restriction. I have this schedule for two weeks from now.

My screen is very clean. I have not had any issues with keeping it clean since I've had this stove.

fire-man: I will pay attention to the smoke spillage and try messing with the draft lever.

My next question is if I'm getting smoke spillage in from the air intake during reload, if I had the Outside Air Kit (OAK), wouldn't that seal this area and eliminate this problem? Would adding the outside air kit help the draft, or is that really not its function?

I have tried opening the window right by the stove a little and it may help a little, its hard to say. It definately does not eliminate the negative draft issue when I'm having that problem. It may help, I really can't tell for sure.

Thanks for the suggestions so far. I forgot to mention in my original post, I took a picture of the back yard facing away from the chimney to give a view of what the layout is. As you can see, I have a few tall oak trees about 60' from the house and then it drops off with a steep hill down about 50' to the river below. The wind usually comes from the NW which would be from along or across the river and up the hill. I've often wondered if this is creating some type of problem with the draft. I have no idea, just a thought after reading that trees and tall building can affect draft.

My home is at the top of a steep hill more than 50 feet above a long wide lake (miles long and wide), on the south shore facing NNW. Wooded between me and the lake, hardwood so pretty exposed in the winter and the prevailing winds are off the lake. I have not had a problem with my draft, have a interior ICC double wall stovepipe and chimney, over 30 feet high.

I'm assuming the problem you have is primarily with a cold stove. If it's with a hot stove, the only thing I can suggest is get that stove pipe enclosed. It;s pretty close to the only difference between your stove set up and mine.

If the problem is with a cold stove then the first thing I would do as a easy cheap solution, expecially since you didn't have a problem with the Fireview with the same set up, is figure out an easy inexpensive way to heat the PH like you heated the Fireview. So, my suggestion is either buy some supercedars, or make your own. If you want to make your own, just collect some sawdust and get some paraffin or some tealights (uncolored), and get a disposable aluminum roasting pan. Either on your PH when it is warm, or on your regular cookstove, heat the wax carefully until it melts. Then dump the woodshaving/sawdust in pan, mix quickly with an inexpensive teaspoon. You'll get either a solid mass you can break into pieces, or lumps of wax- bound sawdust, depending on percentage wax/sawdust. Put the clumps into a covered used platic container (like a large cottage or ricotta cheese container) near the stove.

Get some 1x 4 or 2x 4 if you don't have scraps of kiln dried wood....I can get free scraps from my local lumber yard...and cut into about 6 to 8 inch lengths. Put about a one square inch piece of supercedar or your homemade firestarter in the PH, with a single piece of kiln dried at an angle over it. Light the starter, and let it warm the stove. It will light, and I am sure will heat the stove and chimney set up at least as much as a hair dryer did with the Fireview, and a lot more conveniently.

If (when) you find it works, then I suspect you could just make a practice of, when starting from cold, loading the stove as usual, but placing a small piece of kiln dried near the center of the door a few inches inside the stove. After loading the stove, wedge a firestarter under that piece of kiln dried, light it, and close the door. Bet it lights quickly, heats the chimney just fine and gets a good draft going.

Worth a try.
 
Ill vote for a OAK. They make perfect sense to me. Ive been running one for about 4 years now. It can only help in this situation.
 
I've done a little reading and have found lots of conflicting information. Does an OAK cause you to loose the stack effect? If so, will I loose draft?
Also, I've ran across the term "neutral pressure plane" but am not sure what it is or how it applies. Can somebody explain this?
 
Your house is a lot like a hot air balloon- warm air wants to push out the top while cool air is being sucked (or pushed from the outside) through the bottom. That's the way draft works in your chimney- warm air (flue gasses) are much less dense than outside air, so they rise and create low pressure at the bottom of the chimney, which in turn draws more air into the firebox and allows for combustion.

An OAK simply takes the house air pressure situation out of the supply air equation. It's colder outside your house than inside, so before the fire starts, yes, you won't have great draft, but you don't need much to start the fire, and air will be going the right way from the start because the chimney will generally be warmed some by the house itself. As soon as you open the door to start your fire, you'll feel cool air coming through the air inlets (from outside) which then rushes up the chimney. Burning a little newspaper right at the flue exit inside the stove prior to starting your fire will aid this effect because it sends a rush of hot air up the chimney which then establishes your draft.

The neutral pressure plane is that spot vertically within your house where the air pressure changes from negative to positive. On my house with it's original windows, the ground floor will remain frost free all season while the upstairs windows are totally frosted over. When its really cold you can't see out of any of them. This indicates warm air being pushed by positive pressure through the gaps around the primary sash and freezing on the inside of the storm. At the ground floor, because of its negative pressure you will find outside air being sucked in past the outside window and warming up as it passes the primary sash, thus lowering its relative humidity, and hence, no frost.

With your outside chimney your situation will never be perfect, but an OAK will prevent your house from competing with it for air.
 
Even with the offset and being outside that chimney "has" to be adequate. It darn near looks like the ideal chimney to me, I can't imagine a stove that is that picky about draft would be built by WS or anyone else. It would be a customer service nightmare. If the stack was 15' with twists and bends I would say the chimney could be a problem but it looks good to me.

What kind of outside temps are you having or have you had problems even in the dead of winter? When was the last time the chimney was swept? I'd start with that since it's already scheduled and if it checks out ok I'd move on to an OAK like others have suggested.
 
My cap up top is a 6" vacu-Stack which is designed to help stop the wind induced down drafts. It is much better with it on, but I still have occasional problems.



My next question is if I'm getting smoke spillage in from the air intake during reload, if I had the Outside Air Kit (OAK), wouldn't that seal this area and eliminate this problem? Would adding the outside air kit help the draft, or is that really not its function?

I have tried opening the window right by the stove a little and it may help a little, its hard to say. It definately does not eliminate the negative draft issue when I'm having that problem. It may help, I really can't tell for sure.

Thanks for the suggestions so far. I forgot to mention in my original post, I took a picture of the back yard facing away from the chimney to give a view of what the layout is. As you can see, I have a few tall oak trees about 60' from the house and then it drops off with a steep hill down about 50' to the river below. The wind usually comes from the NW which would be from along or across the river and up the hill. I've often wondered if this is creating some type of problem with the draft. I have no idea, just a thought after reading that trees and tall building can affect draft.

Regarding an OAK: You must open the correct window (not just any window) before opening your stove for reloading or initial fire start, to evaluate how effective an OAK will be. If there is any wind, you need to open a window on the upwind side of the house. Opening one on the downwind side of the house will exacerbate negative draft. Also, be very aware of any exhaust fans operating, i.e. bath exhaust fans, clothes dryers, fresh air heat exchanger, condensing furnaces, etc. Verify an incoming flow from an open window by holding a candle or match in the opening to know the direction of flow. Be aware that very little wind speed is required to effect a draft-killing pressure differential around your home, and the effect is magnified by the size of the building. If you determine you must open a window on a certain side or area of the home to improve the draft, any OAK you install will need to source the outside air from the same area.

As I understand your description, the prevailing wind blows up a slope toward your home, which is set back a bit from the edge of the "plateau". If this is correct, you may very well have considerable downdraft at your house. Although I don't think this would affect your draft if you have the proper cap - it would just tend to carry the smoke from the flu downward rather than allowing it to rise naturally. However, any downdraft flow may be creating a lower pressure in the house in unexpected ways - i.e. creating low pressure areas at soffitt vents that is also reducing the pressure in the living areas.

I'd suggest you keep a journal for a while, noting the draft quality, weather conditions (especially wind), operation of any power exhaust vents, and the effect any intentional venting fix attempt (opening a window) has on the draft quality. Eventually you'll see the pattern and can then focus on identifying the cause and a solution. You may end up amazed at how simple and effective the solution is.

Edit: BTW, I have found that my PH is VERY sensitive to anything that creates a negative pressure in the house, and my house is FAR from being air tight. I always open a window several inches for initial start and usually keep a window cracked for the duration of a burn. I think the PH achieves it's efficiency by using such a minimal amount of combustion air that it is inherently much more sensitive to inside vs. outside pressure differentials - i.e. the PH does not create as strong a draft in the combustion process as most other stoves do. It just seems logical that the total volume of gas flow is lower and slower per btu output. Your experience with the PH vs. the Fireview seems to support this notion.

Also, what is your flue size?
 
For some reason, your pics did not load when I first opened this thread. After reloading the thread and viewing your pics, I'd suggest you try this:

Remove the exterior cleanout cap from your stack and leave it off. Evaluate if this has a positive overall effect on your draft. As I posted earlier, I suspect the total gas flow volume from the PH is lower than on other stoves. That said, the total amount of hot gas entering the flue is also low, which would decrease the stack effect. Removing the cleanout will neutralize the stack and allow the "pumping" action of combustion in the stove to more easily move the combustion gases to the stack if all other factors are equal, i.e. if you were easily able to achieve positive draft with the FIreview. You actually may find that this will create excessive draft and you will need to install an orificed cleanout cap to reduce the draft somewhat.
 
I'm looking for some ideas to see what I can change or add to increase my draft. ....

I know this is an old post.. so, pardon if if this response is against the rules

Part of the problem is the chimney is outside and getting cold, plus, it has a couple of bends in it. It looks like you have a clear path from the stove to the roof from your photos.. you might want to consider moving the chimney inside, and having it go straight up from the stove.

This will do two things:
1) increase draft (a warm chimney works better)
2) reduce pressure drop ( each bend reduces draft)
 
I have a really poor draft situation in my home as well with a 30, a 60 and 2 90 deg bends before heading up a 16 ft masonry chimney.
I installed an Exhausto fan on top of the chimney (approx $1000 plus my labor) however all problems solved. Most of the time the fan is minimum speed. During new fire start, it's at half speed and during reload it's at full speed. No smoke smell under any conditions and super easy starts-instant draft.
 
WarminIowa,

What happened? Issues resolved?

I reread this thread. Seems to me folks missed the point that you were fine with the Fireview. I don't think there was anything the matter with the pipe. Just needed a way to heat the pipe before lighting a fire, to get draft going.
Wonder if you ever tried using a full supercedar to get a quick hot flame with little if any smoke.
 
Yea, what happened? I remember this thread....

I personally would have moved the pipe inside, it would look cool, work better, AND, give you even more heat from the heat coming off the long pipe going up insdide the room.
 
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