Newbie - Insert Stove?

[Van]

Greetings everyone from still warm Arkansas! We'll be in the 80s tomorrow.

I have been reading enough posts now that I decided it was time to join the forum.
I seek advice on a replacement insert stove for my older fireplace.

I have an 1800 sf ranch house here in Central Arkansas built in the early 80s.
Our temps in Winter here hover on average around 40F sometimes dipping into the 20s occasionally.
The existing fireplace is a "Heatform" prefab firebox that they built the masonry around.

Am looking for an insert to place within my older "Heatform" prefab.
Started with the Neo 1.6, which will fit without cutting the 1/8" steel firebox.
I was told by a respected source on this forum that the Neo 2.6 would be better as it can produce more heat if I ever need it.

While any insert will require cutting thru the "Heatform" shell to fit the flu liner, the 2.6 will require me to cut out much of the back (with a sawzall or angle grinder) in order to fit it. The "Summit" is a very close fit, but according to my measurements it may not require any cutting out any of the back of the firebox.
Too much heat potential?

I have heard of one drawback of the Neos. Here we have the occasional ice storm that will cut off power for several days. With a flush mounted stove no power would be available for the blower.
I read that the Summit will blow heat without power, no?

Thanks for your suggestion,
Van

 

[woodhog73]

I'm not familiar with the stoves you mentioned but I'm not sure how the blower would operate without power ?

I went with a non flush mount. A small portion of the metal fire box did need to be cut. With a non flush mount you do get radiant heat from the exposed area so if you have a power outage it's still going to give you some heat without a blower. I have a blower but I don't use it too often. I find the inserts exposed area radiates enough heat for my needs. I do however use the blower if I want to heat up the house quick, but after 10 minutes or so I turn it off and leave it off.

 

[Van]

Thanks Woodhog
The PE SUMMIT may be the one then, though w/ the extension i will have to extend the fireplace hearth into the laminate floor below. Only got 20" and need 22". Bummer

 

[jatoxico]

Have you already established that the current fireplace can be fitted with an insert? Not all pre-fabs can.

 

[mellow]

NM... didn't see you had masonry around yours. I still would be carefull cutting anything out.

 

[Van]

Yes, I have measure the firebox pretty accurately.
The Summit will just fit.
The existing fireplace has an ash cleanout 4x9" that I will use for combustion supply.
Also has a vent along the hearthstone right at the front of the fireplace that I am wondering if I need to plug
given the cleanout.

Pictures show fireplace and ash drain with vent at front

 

[begreen]

Have you already established that the current fireplace can be fitted with an insert? Not all pre-fabs can.

Not a problem. A heatform is not the same as a ZC fireplace. It's a metal form in a masonry surround.
https://www.hearth.com/talk/wiki/heatform/

 

[woodhog73]

NM... didn't see you had masonry around yours. I still would be carefull cutting anything out.

I'm not sure what the OPs set up is regarding prefab or not.

I know with mine it's a masonry cement block chimney that was built with a metal firebox. It was built with hollow cavities above the firebox with vents so hot air could escape. It actually heated very well as an open fireplace but like all open fireplaces it was not efficient. I would burn through 3 or 4 hardwood splits in 30 minutes.

In my case cutting the metal firebox had no negative effects ( other than never being able to return the fireplace to an open fireplace).

Assuming the OP is ok with cutting the metal firebox, I guess if I were the OP I'd probably choose an insert that requires the least amount of cutting.

Also in regards to the laminate floor needing to be extended 2 inches. In my opinion it's worth it to get the non flush because with the non flush you do get more radiant heat. I find the blower annoying at times and happy that I really don't need it usually. If I had to run the blower constantly I might get frustrated.

Unless you just want the look of the flush stove my suggestion is the non flush for a little better radiant heat. Just my opinion

 

[begreen]

Van, have you considered the PE Super instead? It is a very capable insert with good burntimes. This seems more right sized for your location.

 

[jatoxico]

Not a problem. A heatform is not the same as a ZC fireplace. It's a metal form in a masonry surround.
https://www.hearth.com/talk/wiki/heatform/

All good. I have one very similar that I keep thinking I'll add a stove to but then I'm not sure I want to feed two stoves. Carry on .

 

[Van]

Van, have you considered the PE Super instead? It is a very capable insert with good burntimes. This seems more right sized for your location.

Begree. Why do you feel the super would be "more right sized"? Not that I am doubting you, I only want to know what your thinking is.
BTW, as the PE Super is smaller there is no doubt about it fitting in my firebox

Also in regards to the laminate floor needing to be extended 2 inches. In my opinion it's worth it to get the non flush because with the non flush you do get more radiant heat. I find the blower annoying at times and happy that I really don't need it usually. If I had to run the blower constantly I might get frustrated.

Now that point is worth remembering Woodhog, thank you.

 

[begreen]

It's a 2 cu ft stove whose btu output is better matched to your climate. It gets some of the longest burn times of PE stoves according to thechimneysweep's in house testing and still will allow you to load N/S or E/W. We live in a similar winter temp area. My next door neighbor has the same firebox in the Spectrum. It's in a 1600 sq ft poorly insulated old farmhouse. When he first got the stove he complained to me that it made the place too hot until temps got in the low 30s. That's burning softwood. I think with a load of osage orange you will see 12+ hr burns and get a lot of heat. Hopefully it will fit the heatform a bit better too.

 

[Van]

There is another matter and maybe I should start a different thread to discuss it.

Installing a new flue insert is only going to give me a total of 12' of flue length from the stove to the cap on top of the existing chimney.
This is 3' short of the manufacturer's spec of 15' for these stoves.
So what I am proposing to do is add three more feet of clay liner 12"x12" by building a mini chimney on top of the existing.
Of course I will have to anchor the new section to the old.
Any warnings or suggestions?
Good weather still in Arkansas to do masonry

 

[begreen]

Yes, a 15' flue is what the stove was tested with. FWIW, a buddy has his Summit connected to a 12' chimney with a 90 and two 45's in the connector. It drafts pretty well, especially when the temp drops below 50F. I'm wondering if you will be able to slip an insulated liner down there? What is the tile liner ID?

 

[Van]

Begreen, you have been a big help in this planning stage, thanx!

the OD of the insulated SS Flex liner (w/ .5" insul) will be 7.75" OD
The Terracotta flue tiles are actually 13 x 13" so there should be plenty of room inside, and I will cut a 10" dia. hole in the firebox for easy passing of the liner through the firebox to the stove.

By the physics the burn rate of the stove will be effected differently by more or less draft, no?
Too much chimney can increase updraft causing the stove to burn out of control. Contrarily too little chimney with too little updraft could smoke the room. Tom at chimnysweeponline explains this question well.
On the PE NEO I was told that chimneys under 15' have sufficient draft to burn wood but not to effectively wash the glass with air, so soot slowly builds up on it.

I wonder if I go to the more expensive "smooth wall" SS flue liner (costs about %30 more) if that would increase the updraft as much as the extra 3' of flue? My cost of material and labor to extend the chimney 3' is going to be a lot more than the extra cost of the "smooth wall" liner
According to the manufacturer a smooth wall flue liner increases draft by 20% over the corrugated flex liners that everyone is using.
PM me and I can give you the name of the distributor that sells the stuff.

I would be interested to know if your buddy has to clean his glass very often.

 

[begreen]

If you are going to upgrade, go heavy duty liner and not double "smooth" wall. Insulating the liner will make a bigger difference in draft.

I've run my buddy's Summit. Their glass stays quite clean as long as the stove is allowed to get reasonably hot. Normally it is totally clear with below 50F burning.

 

[woodhog73]

Too much chimney can increase updraft causing the stove to burn out of control. Contrarily too little chimney with too little updraft could smoke the room.

According to the manufacturer a smooth wall flue liner increases draft by 20% over the corrugated flex liners that everyone is using.

I would be interested to know if your buddy has to clean his glass very often.

Your concerns remind me of myself when I first got my stove. Couple of thoughts if you don't mind.

Regarding the stove over firing or smoking the room. First your wood selection can play into this just as much if not more than your stove set up. Prior to EPA regulated stoves and the testing that was required to come with them, folks burned old smoke dragons according to their instincts and it turned out fine, I know I grew up in a house heated with wood.

Your modern stove is unlikely to burn out of control over a few feet difference in chimney height. Honestly 12 feet is probably going to work just fine it's only a few feet lower than the 15 foot test heights. And again thank the EPA for that one because the stove company wants to make that stove achieve as high efficiency rating and long burn time as possible. If that happens using a 15 foot chimney that's fine. Doesn't mean a 12 foot chimney is gonna mess all that up. My guess is you wouldn't even notice a difference.

Regarding too little chimey smoking up the room ? No chance. I refuse to believe a modern stove connected directly to a liner using 12 foot of chimney is going to pour smoke into your room. Once again in this scenario it might come down to your wood more than the lack of 3 feet of chimney. Burning fresh cut pine that was submerged in water ? Ya it might smoke some. You get my point.

As for your liner. A smooth liner does most likely draft better. It might also clean better . But do some research. If it's a smooth flex liner I'm not sure if it lasts as long ?? This is an area for a sweep to chime in on smooth vs non smooth liner.

Lastly in regards to cleaning the glass. Once again I place more emphasis on quality of wood and your burning habits. Smoldering fires, lack of flames, will dirty your glass. If you burn hot fires and maintain flame the glass stays clean. I really think your wood and how you burn will have more impact on keeping your glass clean than 3 feet of chimney.

When ( not if ) your glass gets dirty just take a paper towel, run water on it until it's saturated, rub it in ash from your stove, and wipe the glass. Take a fresh wet towel to wipe clean and you end up with clean glass.

 

[Squisher]

I have to disagree. I think you are undervaluing the advantages of a taller chimney. A taller chimney can account for all sorts of other shortcomings much easier than a lower one I think. Taller chimneys pull harder and I see lots of really tall chimneys working quite well with what I would call less than ideal installations or appliances.

 

[begreen]

Depending on the stove design, the routing of the secondary air system can often require at least 15 ft of chimney so that there is sufficient draft to pull air through the secondaries. There are several stoves that need this. Every year we get several cases where a few feet additional chimney has made an appreciable improvement in burning, especially during milder weather. Most PE stoves have a simpler, large and direct secondary supply which happens to let them breathe easier, but this is not the case for all EPA stoves.

 

[woodhog73]

I have to disagree. I think you are undervaluing the advantages of a taller chimney

No not at all. I'm not saying in a perfect situation that using a 15 foot or taller chimney is not ideal, best case scenario. What I'm saying is that stove would most probably perform just fine with a few feet less.

In other words no way would I go about reconstructing the masonry chimney adding another 3 feet to it just to satisfy the EPA mandated regulations the manufacturer is forced to work with.....when in fact the stove will work just fine with 3 less feet of chimney. No it won't burn out of control, No it won't smoke up your room, no it won't dirty up your glass, over 3 feet of chimney.

12 feet of chimney is fairly decent. Prior to EPA stoves no one would have given this much thought at all.

All I'm saying is don't over think too much. There is room to apply common sense reasoning here. If you want text book performance according to the manual sure run 15 feet of chimney. If your adding to your existing chimney why not make it double bring it to 24 feet. Where to draw the line ? At what cost ? Especially if you can use your existing 12 feet of chimney, and still get a good burning and acceptable stove ?

Yes 15 feet or more is better. But that doesn't mean what you have won't work either. Comes down to how much you want to invest in time and money and what your expectations are. In your warmer climate I think no matter what you do you will be pleasantly surprised by adding a wood stove regardless if it uses a 15 foot chimney or a 12 foot chimney

 

[begreen]

While in this case for this stove I agree, as a general rule I do not. Most EPA stoves require at least 15 ft of chimney to perform well. We have seen this be the case many times over. Go back over the threads complaining of no heat from the stove, that weren't a case of poor wood.

 

[Squisher]

I would think a super or summit insert will work fine on the OP's chimney, espescially if insulated and burned with dry wood.

 

[bholler]

In other words no way would I go about reconstructing the masonry chimney adding another 3 feet to it just to satisfy the EPA mandated regulations the manufacturer is forced to work with.....when in fact the stove will work just fine with 3 less feet of chimney. No it won't burn out of control, No it won't smoke up your room, no it won't dirty up your glass, over 3 feet of chimney.

Honestly I agree I would try it as is before adding to the chimney. But there is absolutely no way for you to know it will work fine. There is no way for any of us to know that for sure.

12 feet of chimney is fairly decent. Prior to EPA stoves no one would have given this much thought at all.

Not true at all old stoves still worked best at about 15' of chimney. So that is always what I would shoot for.

If your adding to your existing chimney why not make it double bring it to 24 feet.

What reason would you have for going to 24'? You may start to have over draft issues at that point.

In your warmer climate I think no matter what you do you will be pleasantly surprised by adding a wood stove regardless if it uses a 15 foot chimney or a 12 foot chimney

In a warmer climate the height of the chimney will be more of a factor. With less temperature differential being a little short may possibly cause a problem.

 

[bholler]

And again thank the EPA for that one because the stove company wants to make that stove achieve as high efficiency rating and long burn time as possible.

Please explain to me what the epa had to do with determining what chimney height gives optimal performance?

As for your liner. A smooth liner does most likely draft better. It might also clean better . But do some research. If it's a smooth flex liner I'm not sure if it lasts as long ?? This is an area for a sweep to chime in on smooth vs non smooth liner.

Smooth wall yes but not the crap 2 ply smooth wall go wiht heavy wall it is smooth wall and it holds up well.

Regarding too little chimey smoking up the room ? No chance.

It can and does. I have seen it many times. Again I cant say one way or another in this situation but you cannot say there is no chance at all.

 

[woodhog73]

Bholler I agree with most of what your saying. Like I said in a perfect world sure 15 feet of chimney is ideal in most all scenarios. But adding 3 feet of masonry chimney can be costly in both terms of money and your time so I was simply saying to the OP that his 12 foot chimney is probably just fine.

Just to clarify my comment on the EPA. Sure 15 to 18 feet of chimney might be the sweet spot for stove performance. But being that the EPA regulates stoves performance, pollution , efficiency etc the manufacturers in a " cover your you know what " will most likely be far less likely to tell a customer that they can probably be fine with a shorter chimney. Their dealers selling the products are probably going to push customers into doing whatever they have to inorder to obtain the manufacturer listed chimney height. They wouldn't want to be on record advising customers that it's ok to use a shorter chimney, thereby reducing efficiency of the stove and putting more particulates into the air. The dealer is less likely to say " but hey you will probably still get good enough performance with the stove so don't worry about it " So they stick to the text book.

Thankfully there are forums like this where people can get opinions and like you said and others have said try it with the 12 foot chimney because most likely it will probably run fine. That's what I meant by the EPA stove.

Ok completely off track but it reminds me of small homeowner chainsaws and the legal requirement small saws under 55 cc or so must be sold with safety chain. Complete garbage and most dealers won't tell you " hey the saw will cut like crap until you replace that anti kick back chain " they don't want the liability so they leave it up to you to figure that out on your own.

Thanks again to forums like this for advice.

On the 24 foot chimney comment I was trying to be funny. Meaning if your going through the trouble to build onto your chimney, dragging heavy cement blocks up ladders and setting up scaffolding don't stop at 3 feet go bigger make it huge. Go big or go home comment. Probably shouldn't have said that. I totally agree 24 feet could cause other issues.

One final thought. I've got a friend who put an old pre EPA stove in a hunting cabin. Looks like an old barrel stove. The chimneys lucky if it's got 8 feet to it. I'm not saying it was the best of installs but it's basically a shack. It does a fine job of heating a small cabin in temps near or below freezing.