I have a problem

[Ratman]

Just one man's opinion.

I believe lowering the stove will help more than the rest of the group believes and I'll tell you why.
Convection and circulation are a large part of heat distribution.

Assuming the rest of the variables are ok:
Chimney & draft correct.
Stove being run at proper temp.

I would purchase new legs and not cut the existing legs. You could cut and not purchase or purchase later but I'd rather have less hassle.

I would lower the stove, heat it full and push some colder floor air at it.

 

[BrowningBAR]

My other question is that to the right of the stove is a very drafty window. I was wondering if all of my heat could be getting sucked out of that window? Keep in mind, the window is not warm and neither is anything on the window sill.

I've attached a photo. I don't think this is the case, but I wanted to throw it out there so everyone had all the details.

 

[elmoleaf]

I also have the Intrepid installed at an old fireplace.
My opinion is there are several issues preventing good heat:

1. Masonry mass is absorbing a lot of heat. The best way to fix that is to move the stove out on to the hearth extension. If I recall, the hearth doesn't require an R value with the bottom heath shield on the stove and the full height legs. Switch the stove pipe collar to the rear exit configuration. Get a black pipe "T", piece of straight pipe, and and premade stove board. It's a relatively easy fix to pull the stove out and install the above items. However, you will need to watch the side clearance to window wall...that'll probably need a heat shield at the wall. You'll find top loading the stove is a much easier than from the front, and allows you to put more wood in the stove.

2. Try running the stove a bit hotter. I'm always typically in the 600-650F range with the cat engaged. This easily heats an open floor plan area of about 30'x24' to 72-73F. (2x4 wall construction with batt insulation, 12-16" attic insulation). My stove sits outside the old firebox on a hearth extension and uses a rear exit "T" connection to the flue. I don't have a rear heat shield. I do have two large steel plates set up inside the old firebox against the side walls behind the stove to keep the masonry from absorbing the rear heat.

3. The window(s) and other leaks may be a problem. If your basement is excessively cold, the cold floors could also be causing discomfort. Sometimes the best way to get more heat is to lose less heat. Spend some time searching for and sealing up drafts. I notice you're in a stone farmhouse. I suspect theres no insulation at the exterior walls....just stone covered by an interior finish? That's always going to be tough to heat.

 

[webbie]

Good comments!

One big problem is that the heat usually soaked up by masonry and released later....in probably not being released because of the wood facing of the FP.

In such a case, little things CAN make a diff.

For instance, as others have mentioned, if the block off plate is any further than 2" up from the lintel of the fireplace, this would allow much heat to go up and soak into masonry instead of flow into the room. A quickie second block off could be fashioned from metal and be placed so that it slopes upwards from rear and lets the heat flow out. Lowering the stove would help this convection chamber function also.....It might be that eventually insulating the rear and side interior wall of the FP may help.

See red line in pic.....

 

[semipro]

I don't think the shorter legs will help as much as you'd like. I think you need to increase your convective heat transfer. The air is probably fairly stagnant behind the stove.

I have a similar install for my Oslo as shown below. Its sits well back inside a masonry and steel fireplace. We are getting a lot of heat from it but I've found that we get quite a bit more if we force some air in at the bottom of the fireplace opening. This forces air up the rear and over the top of the stove, the hottest part. I'm just using a small 22 watt fan right now for experimentation. Of course the air that exits above the stove tends to keep rising after that to the ceiling but that's another issue.

Good looking dog in your avatar by-the-way.

 

[BrotherBart]

I think a combination of the short legs and Craig's suggestion for the angled block-off plate sloping up to and even with the lintel will make a big difference. I changed my block-off plate to work that way the second season with the new stove and the difference was very noticeable. Since then I don't have to run the blower as much. The heat just rolls up and out of the fireplace.

 

[semipro]

I think a combination of the short legs and Craig's suggestion for the angled block-off plate sloping up to and even with the lintel will make a big difference. I changed my block-off plate to work that way the second season with the new stove and the difference was very noticeable. Since then I don't have to run the blower as much. The heat just rolls up and out of the fireplace.

That's a great suggestion. I may have to add an angled block-off plate and see how that works as part of my experimentation. I'd rather not use a fan as that means more electricity use and more noise. I only want to hear the fire.

I guess I'm not understanding how lowering the stove is going to help though. I supposes it exposes more of the top plate for thermal radiation to the room but given the angles involved I can't see that changing overall heat transfer much. On the other hand, if air is blown in below the stove the decreased clearance between the top of the stove and the fireplace would increase air speed, throw the air farther into the room, and may increase heat transfer out of the top of the stove by breaking down any existing boundary layer. Sorry, getting too geeky here.... going to go work some firewood.

 

[BrotherBart]

I guess I'm not understanding how lowering the stove is going to help though. I supposes it exposes more of the top plate for thermal radiation to the room but given the angles involved I can't see that changing overall heat transfer much. On the other hand, if air is blown in below the stove the decreased clearance between the top of the stove and the fireplace would increase air speed, throw the air farther into the room, and may increase heat transfer out of the top of the stove by breaking down any existing boundary layer. Sorry, getting too geeky here.... going to go work some firewood.

For one thing if the stove is even with or sticking up above the lintel it would be pretty hard to have an angled block-off plate that slopes up to the lintel.

 

[BrowningBAR]

A lot of good suggestions and information. I appreciate it, a lot! And to the people suggesting the use of a fan, I have. I have had a fan pointing under the stove, to the left side of the stove, to the right side, and I put the fan behind the stove pointing out and felt little difference.

If I rework the block of plate as suggested and bring the stove out of the fireplace by ten to 11 inches (about 15 inches if you include the front lip of the stove) does everyone feel my heat output should greatly improve?

Because, right now I can't heat a 15x13 room with the current setup. It didn't even bring the room up to 70*. I'd say it was about 65*. At this point it seems like a waste of time and wood to get the stove going, which is a bit frustrating.

 

[BrowningBAR]

Good looking dog in your avatar by-the-way.

Thanks, we rescued him just under a year ago. Fantastic dog.

 

[crazy_dan]

I would buy the legs vs cutting the ones I do have for 2 reasons.
1: not sure how it would work with insurance, codes, and such
2: Most of the legs I have seen have had some form of leveling means be it a bolt or something fancier. as getting them all cut exactly would be a little tricky.

I would plastic the window on the outside of the house, I do this every winter. you will need some lattice for wrapping the plastic sides up with to give it strength and I use double head form nails so they are easier to pull. but I guess one of them indoor kits may work and they are clear so you can see out of them if that would be a deal breaker. 3 or 4 of these little things can ad up to a world of difference.
I know putting plastic on my windows makes a huge difference. so that window may be a huge part of the problem. if any other windows are drafty even a little plastic them too, unless you are trying to heat it up outside.

 

[Lanningjw]

Can you make a steel liner for the fireplace that the stove could fit into? That would push out the heat into the room.

 

[branchburner]

Forgive me I know you said its not an option, but I would really consider moving the stove out of the fireplace. Extend the hearth should not be difficult, add a section of pipe and I would think your problem would be solved. Also now you"d be able to see the entire stove.

If I extend out the hearth the easiest way to do it would give me an additional 11" That would expose about 85% of the top and side. Would that be enough? I will do this as a last resort. In fact I will be calling my installer on Monday to see what it would cost for him to come out or if it is something I can tackel on my own for the 're-install'. I can handle the hearth extension on my own without a problem.

I think of all the options this will give best results. Shorter legs will allow more airflow over the top, but there is still not very much airspace there. Bringing the stove out even a few inches will not only give more radiant heat to the room, it will open up a bit more space behind the stove for convective airflow.

I think Craig is right, your masonry is soaking up all the heat and has no way to radiate it back to you because of the wood. Imagine having a huge masonry heater and then insulating it - in essence, that is what you're doing. So the masonry will keep its heat much longer, but the heat is of no use to you.

I have nearly two feet of exposed brick above and to the sides of my stove, and it gives back a lot of heat. The stove is about 80% out of the hearth, so radiation can occur in all directions out into the room, not just straight out the front like yours. Plus, the extra space behind allows the floor fan to move enough air to be really useful. With a foot of open space above and to the sides, 6" below and 18" open behind the stove, there is a lot of airflow. I think your opening is just too small for a fan to make much difference.

Shorter legs will not change the total space, just shift the positon of it. I would expect some improvement, but not a lot. To experiment, instead of cutting the legs, you might want to just remove them and block the stove temporarily. If that is not the solution, you still have the legs.

I supplemented my upper smoke shelf blockoff with a loose fitting piece of metal right at lintel level. It is not a blockoff, really just a heat reflector. I figured, as some have suggested, that the masonry above and behind the stove was stealing way too many of my BTUs!

 

[BrowningBAR]

I think we might have found the problem. We did a smoke test to see where the smoke travels inside the fireplace. Turns out the smoke goes to the back of the fireplace and right up to where the opening was. I think there might be a good size gap in the block off/insulation that I can not see.

Is it possible that I could be suffering from this much heat loss from a gap? Please tell me 'yes'... because that would make things a lot easier.

Might still bring the stove out a bit, though.

 

[branchburner]

Try the blockoff solution first - it's easy and will give at least partial results for sure. It sounds like you have airflow there, so you are losing even more heat than just what the masonry is absorbing.
Is the liner well sealed with a top plate where it exits the chimney?

 

[ansehnlich1]

something ain't right with this whole setup, and it's something obvious. my bet is heat's goin' right up the chimney.

that stove, properly installed in the same spot, properly operating, will heat that space, masonry sink or not.

somethin' ain't right here folks.....

 

[BrowningBAR]

something ain't right with this whole setup, and it's something obvious. my bet is heat's goin' right up the chimney.

that stove, properly installed in the same spot, properly operating, will heat that space, masonry sink or not.

somethin' ain't right here folks.....

I hope it is simply the heat going up through the chimney. That would be an easy fix. Extending the hearth and bringing out the stove will require more time, effort, and money on my part.

The other stove is humming along and I had part of the house at 90* last night.

 

[Hogwildz]

With that gap, if there is any other gaps above there anywhere, there could be a good flow going just sucking the heat from the stove & the room.
Get the block off sealed tight. And if you still have a problem, I suggest Lanning's suggestion. Take some sheet metal and build side & top reflectors to direct the heat back into the room, instead of it getting sosked up by the stone.

 

[semipro]

I guess I'm not understanding how lowering the stove is going to help though. I supposes it exposes more of the top plate for thermal radiation to the room but given the angles involved I can't see that changing overall heat transfer much. On the other hand, if air is blown in below the stove the decreased clearance between the top of the stove and the fireplace would increase air speed, throw the air farther into the room, and may increase heat transfer out of the top of the stove by breaking down any existing boundary layer. Sorry, getting too geeky here.... going to go work some firewood.

For one thing if the stove is even with or sticking up above the lintel it would be pretty hard to have an angled block-off plate that slopes up to the lintel.

As my photo shows our stove still sits below the masonry arch. There's still a good 12-16" between the top of my stove and block-off plate so at least the heat wouldn't get trapped in that space.

Point well-taken though.

 

[BrowningBAR]

I figured I would update this thread.

The problem seems to be resolved. This is what was done:

1. We extended the hearth out by 12" with field stone from around our property. Came out great and the hearth looks as old as the house.

2. I bought the short leg kit from Black Swan.

3. Sealed up some gaps in the fireplace. Not sure if these gaps lead anywhere, but I wanted to remove any possibility for heat loss.

4. We brought the stove out of the fireplace by 12". In the end that worked out great as we can now top load the stove, which is sooooo much easier.

5. Bought a bigger fan to put behind the stove. At the two lowest settings it really pushes the heat out.

It was a little frustrating, and a bit more expensive than I would have hoped, but it is now doing it's job. I appreciate everyone taking the time to give me their thoughts on my problem. I look forward to everyone helping me with my next stove problem.

 

[Shari]

Pictues please!

Shari

 

[BrowningBAR]

Pictues please!

Shari

Pictures will be coming in a few days. I also need to take photos of my ridiculous wood score for a thread I have in the Wood Shed area.