M55 - disappointing results

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I would like a piece of this bet. It is VERY common whether pellet or wood for a large masonry chimney to be a giant heat sponge. Install a block off plate and keep the heated air in the room.

This chimney is huge. It has 3 flus through it. 2 are permanently sealed off at the top and the stove vents through the 3rd. The chimney is roughly 35ft tall and roughly 6 ft by 4 ft rectangular.

Do you think the block off plate alone would be sufficient or only in addition to the OAK?

Thank you
 
Personally, I would bet that an insulated block off plate would trump installing an oak. Do the block off, then revisit the stoves performance. There is nothing wrong with taking this one step at a time.
 
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Personally, I would bet that an insulated block off plate would trump installing an oak. Do the block off, then revisit the stoves performance. There is nothing wrong with taking this one step at a time.

So is the idea that the chimney is sucking up lots of hot air? I can't visualize this because the stove blows the air out into the room and because the flu is basically sealed off (shouldn't be much 'chimney effect' I dont think).
 
Just took a look at the on-line manual and can understand your confusion. They do not show a block off plate when running a chimney liner to the top. Guess what you are looking to do is a combination of both of those installs they show. The only option they show for an OAK is out through an exterior wall. The manual is not as good as it could be :(

Many have heard that story about not needing an OAK (myself included). Without an OAK, you are making those drafts more noticeable.

Once you get the insert install sorted out, you need to concentrate on insulating and sealing up as many leaks as you can :)
 
So is the idea that the chimney is sucking up lots of hot air? I can't visualize this because the stove blows the air out into the room and because the flu is basically sealed off (shouldn't be much 'chimney effect' I dont think).
Think of it this way, hot air rises, so its going into your chimney, and even though it may not be exiting to the outside at the top, the hot air is trying to heat all that cold block or whatever material it is made of, thus soaking the heat from the air. It's really the same principle as trying to heat your house, all the objects in the house have to warm up as well, except once those objects get warm, normally they tend to stay warm as long as the heat stays in the house because there isn't a cold side sucking the warmth from those objects, save for maybe some exterior walls. With the chimney, it just keeps sucking the warmth from the air and not allowing it to heat the room. If that makes sense.
 
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Personally, I would bet that an insulated block off plate would trump installing an oak. Do the block off, then revisit the stoves performance. There is nothing wrong with taking this one step at a time.
I have a stone farmhouse, no insulation, old windows and doors etc. We like the looks so we will not change. However, when I installed my stove, I immediately blocked off the damper opening and insulated. I did have drafts as well (during the polar vortex esp.)and now installed an OAK thru the ash clean out. Drafts are cut down significantly too.

Start with the chimney would be my suggestion.
 
(broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=141&d=&l=en)

Follow the link above and check out this vertical termination cap from ICC for their Excel Pellet line. I have used this on several installs now and have had positive results. With the use of this cap, you would allow your combustion air to enter into the chimney cavity your liner is running through and avoid having to run flex all the way up to the top of the chimney. (Not sure if you insulated your liner but if not, I would suggest doing so). You then would want to definitely install a block off plate at the damper level and along with the 4" hole you'll need to cut for your liner, you also would want to cut a hole for a piece of flex aluminum for your OA- I believe it is a 3" intake on that unit. You will need to engineer a way to keep the 3" flex secured to the block off plate (there are several ways to do this) and then seal up the joints around the block off plate and penetrations. Leave some slack in the flex so you can pull the insert out far enough to reach around and disconnect when performing service (take advantage of the service rails available or make your own, it makes life a lot easier). This is a good solution for insert installs with interior fireplace locations- these situations are usually a little more difficult to be able to provide outside combustion air to the unit. Good Luck!

(broken image removed)
 
(broken link removed to http://www.icc-rsf.com/main.php?t=chem_produits&i=141&d=&l=en)

Follow the link above and check out this vertical termination cap from ICC for their Excel Pellet line. I have used this on several installs now and have had positive results. With the use of this cap, you would allow your combustion air to enter into the chimney cavity your liner is running through and avoid having to run flex all the way up to the top of the chimney. (Not sure if you insulated your liner but if not, I would suggest doing so). You then would want to definitely install a block off plate at the damper level and along with the 4" hole you'll need to cut for your liner, you also would want to cut a hole for a piece of flex aluminum for your OA- I believe it is a 3" intake on that unit. You will need to engineer a way to keep the 3" flex secured to the block off plate (there are several ways to do this) and then seal up the joints around the block off plate and penetrations. Leave some slack in the flex so you can pull the insert out far enough to reach around and disconnect when performing service (take advantage of the service rails available or make your own, it makes life a lot easier). This is a good solution for insert installs with interior fireplace locations- these situations are usually a little more difficult to be able to provide outside combustion air to the unit. Good Luck!

(broken image removed)

Thanks for the advice. I will look into this.

I also found this cap which supposedly allows for both venting and make up air. Not sure how they're kept totally separate, though. http://www.firesidechimneysupply.com/13-chimney-caps/co-linear-chimney-cap.html

Assuming it works, this would have the benefit of keeping exterior (cold) air out of the chimney. Your suggestion would too - but only to the extent that I could really effectively seal off the stove (while allowing the vents to go through).
 

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I cannot add much to solve your particular problems but can reassure you that an M55 is capable of putting out 55k BTU on #5.
We heat 2000 sq ft of an1815 house with ease on #3.
I found several hot air leaks by using an IR gun.
I'd use an IR gun around your chimney and see where the heat is going.
 
Great discussion on the OAK for a masonry chimney, I am in the same predicament with my installation and I've been researching how to get one in. Looks like three options: 1) drill a hole though the masonry and slip line a vent pipe, but I don't really like the idea of altering the structure. 2) go through the ash dump to clean out in basement, then up to sill to a vent - seems like a lot of pipe to suck through, and the dump is under the stove so I don't think the pipe will fit, and 3) go up the chimney beside the vent. I saw a schematic of this somewhere that showed the outside air going just above the smoke shelf, and a block off plate so it sucks from the flue. The cap of the vent needs to be vented so fresh air can come in, like the ones posted above.

I currently have the ash dump open, and there is a strong draft up the clean out in the basement. I figure that is where most of my combustion air is coming from, and the makeup is coming from the bulkhead, which is better than my living room but the basement is much colder now with the stove running, as well as the furnace running much less.
 
I had to look to see if it was April Fool's Day!!! 5000 square feet and little or no insulation? You have got to be kidding! I can't believe others here are actually going along with this! How many btu's is your furnace(s)? Who told you that the stove would heat your house? Get your money back ASAP.

Where in the US are you located?
 
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Regarding the picture you posted of the flame, it looks a lot smaller than mine on four even, you may want to trim up the fuel and/or combustion air. Or maybe mines just cranks more because I asked the dealer to open the hopper feed a little when I had the switch problem?

I find that my stove is most effective when I over-heat the stove room to 80ish for periods, then move some heat around with a floor fan, as I have a lot of heat sucking windows and nearby stairwell that make it tough to get good heat movement using a normal thermostat setting. Then again, I can also pretty much shut the stove off if it's above 45 during the day, and can be above 70 inside, so you definitely got something going on. I still think you should be able to roast yourself out of the stove room at that temp even with a leaky house
 
He pretty much said he wants to heat the room and nearby area, no? I assume he has some other heat for the rest of the house
 
I had to look to see if it was April Fool's Day!!! 5000 square feet and little or no insulation? You have got to be kidding! I can't believe others here are actually going along with this! How many btu's is your furnace(s)? Who told you that the stove would heat your house? Get your money back ASAP.

Where in the US are you located?
My house is only about 2800 sq. ft and not insulated. It was built in the late 1700's. What they did was use field stone, double wall, with an air gap between thewalls. Cover the outside with horse hair mixed into plaster. You get very wide window sills. Quite common actually. You need to get the stone/ plaster walls warm and then it works quite well. Also, very cool in summer. I'm in PA.
 
No mention of the temp inside when the stove was fired up. It takes a long time to get the walls, floor, furniture and in the case of the kitchen appliances up to temp before the room air temp starts coming up. Takes six or seven hours to get the air temp up in my uninsulated basement running the pellet puppy flat out before things level out.

Everything in the room and the walls are huge heat sinks until they are warmed up.
 
My house is only about 2800 sq. ft and not insulated. It was built in the late 1700's. What they did was use field stone, double wall, with an air gap between thewalls. Cover the outside with horse hair mixed into plaster. You get very wide window sills. Quite common actually. You need to get the stone/ plaster walls warm and then it works quite well. Also, very cool in summer. I'm in PA.
Having been born and raised in Montgomery county, I'm very familiar with the old farmhouse construction. I know that an insert pumping out maybe 40,000 btu's is going to work like heck to try to get those walls, floors and furniture even close to warm enough to satisfy everyone. You need something that can pump out two or three times that many btu's. And that ain't a pellet stove!
 
I see that you are 'hoping' to heat just 1000 square feet of the house but you also mentioned you have an unconditioned basement. Is the ceiling in the basement insulated or uninsulated like the walls? The fireplace evidently is on an outside wall so that's another big heat sink. Have you tried blocking off the rooms you plan to heat? Start with just the one? I would give my coal speech but I fear that it falls on deaf ears anyway. A 90,000 btu coal stoker insert for some reason just doesn't make sense to a lot of people........... ::-)
 
I have to add- I grew up and lived in Western MD and Eastern WV- do you live an old stone home? If so- how long have you lived there?

I had very good friends of mine that went through 2,000 gal of propane a year to heat their stone farmhouse. Yes- 2,000 gal a year. It takes a lot, and I mean A LOT of BTU's to constantly run in order to heat that stone and plaster up. I would imagine you would not need an OAK in that house either- direct the warm air up and the cold air will pull from the bottom.

Heck I don't run an OAK and I have a fairly tight house at 3,000 sq ft in Montana and I heat my home fine with a FS M55.

I would love to know more about the home you live in, the layout and then make some recommendations. Most folks I knew with old limestone houses ran solid wood stoves ALL DAY just to keep it at 65 deg. If you're looking for higher, you may be pi*ssing in the wind.
 
If you house truly has little insulation other than the attic and the walls are minimally to not insulated and there is 5,000 sq feet as has been said already you would need 3-4 wood burning devices running almost continuously to heat that home to something other than moderately frigid.

Even a really well insulated newer house would still require 2 extremely large wood burning stoves to have the hopes of heating that house (5000sq feet).

And I know you were hoping to only heat that one solitary room, but the entirety of the rest of the house is such a heat sink that it may not be possible to get even an acceptable amount of heat into that single room. And if it the temperatures truly drop the stove may be a running but you may never notice a significant benefit unless you are 5-8 feet away from it.
 
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I have to add- I grew up and lived in Western MD and Eastern WV- do you live an old stone home? If so- how long have you lived there?

I had very good friends of mine that went through 2,000 gal of propane a year to heat their stone farmhouse. Yes- 2,000 gal a year. It takes a lot, and I mean A LOT of BTU's to constantly run in order to heat that stone and plaster up. I would imagine you would not need an OAK in that house either- direct the warm air up and the cold air will pull from the bottom.

Heck I don't run an OAK and I have a fairly tight house at 3,000 sq ft in Montana and I heat my home fine with a FS M55.

I would love to know more about the home you live in, the layout and then make some recommendations. Most folks I knew with old limestone houses ran solid wood stoves ALL DAY just to keep it at 65 deg. If you're looking for higher, you may be pi*ssing in the wind.
X2 Hey threerun I grew up in frederick area.
 
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Didn't I see somewhere on here that there is a single pipe which accommodates both exhaust venting and OAK, with one line running inside the other and the exhaust prewarming the combustion air for greater efficiency? IIRC, this might be a solution for you.
 
Didn't I see somewhere on here that there is a single pipe which accommodates both exhaust venting and OAK, with one line running inside the other and the exhaust prewarming the combustion air for greater efficiency? IIRC, this might be a solution for you.
Selkirk dt venting.
 
Hey Bob, thanks for filling in my memory gap! Embarrassing, especially since their ad is at the top of the page!
I belive harman also sells their own version,just not widely advertised.Most stove mfg.s are going to push this more,as it makes the stove more efficient.And there is a break point in cold temps that a normal oak should be unhooked.
 
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