Overheating stove in Hearth

[faultymechanics]

Just had a company tell me they don't "suggest" installing their freestander in the fireplace because it could overheat due to being somewhat enclosed.


Anyone ever heard of this? I feel like they're probably just covering themselves liability-wise and that temps can be regulated with a thermometer or something to keep me aware of stove temps.

 

[Highbeam]

Just had a company tell me they don't "suggest" installing their freestander in the fireplace because it could overheat due to being somewhat enclosed.


Anyone ever heard of this? I feel like they're probably just covering themselves liability-wise and that temps can be regulated with a thermometer or something to keep me aware of stove temps.

Many modern stoves are much less controllable than you would like. Reason being they use high firebox temperatures to burn clean and satisfy the EPA.

You should have at least one thermometer on your system to monitor temperatures regardless of installation methods.

The actual manufacturer told you not to put their stove into the fireplace?

 

[faultymechanics]

Many modern stoves are much less controllable than you would like. Reason being they use high firebox temperatures to burn clean and satisfy the EPA.

You should have at least one thermometer on your system to monitor temperatures regardless of installation methods.

The actual manufacturer told you not to put their stove into the fireplace?

No they didn't say not to. I was mentioning my plan and he specifically said they "suggested" not installing them in the fireplace and using an insert.

 

[EbS-P]

Just had a company tell me they don't "suggest" installing their freestander in the fireplace because it could overheat due to being somewhat enclosed.


Anyone ever heard of this? I feel like they're probably just covering themselves liability-wise and that temps can be regulated with a thermometer or something to keep me aware of stove temps.

I think the temps can get higher. I have a cheap pellets stove convection blower sitting behind mine in the fireplace. I use to the keep stove top temps in check. And an Auber AT200 temp alarm.
Edit….

I consider my install safe as did the pro who installed manual has section about fireplace installs. The install location has increased the likelihood of a temperature excursion. It’s still small. All stoves can be over fired.

 

[faultymechanics]

I think the temps can get higher. I have a cheap pellets stove convection blower sitting behind mine in the fireplace. I use to the keep stove top temps in check. And an Auber AT200 temp alarm.
Edit….

I consider my install safe as did the pro who installed manual has section about fireplace installs. The install location has increased the likelihood of a temperature excursion. It’s still small. All stoves can be over fired.

My plan is to order one of those heat powered fans to put on the top. I totally understand the idea but I feel like it is something I can regulate with a fan and a thermo on the top of the stove.

Does that seem unreasonable? We aren't using this as a main source of heat some im thinking regular sized fires will be fine, I just need to practice safe burning.

A couple larger and smaller stoves I've seen have "installed in fireplace" instructions (mainly jotul).

 

[EbS-P]

Does that seem unreasonable? We aren't using this as a main source of heat some im thinking regular sized fires will be fine, I just need to practice safe burning.

I think those are fine fire every day but they really don’t move much air. I had an near over fire /overfire this year. One large really dry, super sappy pine split with some other wood on a hot bed of coals. 120 cfm was able to keep the temps at 800 on the top 1/3 way to the the edge and 900 in the top center. Never got my liner, at the 4” above the collar, above 750. Baffle and air deflected were glowing. I wasn’t wanting a big fire it wasn’t a big load and I turned the air down at what I thought was the right time. It was kind of gusty outside maybe 30 degrees. now way I could reach the air intake with the stove hot. Don’t want to create an explosion by sealing it all the way off either.

I’m glad I had the big blower. I use it less than 1/2 the time.

 

[faultymechanics]

I think those are fine fire every day but they really don’t move much air. I had an near over fire /overfire this year. One large really dry, super sappy pine split with some other wood on a hot bed of coals. 120 cfm was able to keep the temps at 800 on the top 1/3 way to the the edge and 900 in the top center. Never got my liner, at the 4” above the collar, above 750. Baffle and air deflected were glowing. I wasn’t wanting a big fire it wasn’t a big load and I turned the air down at what I thought was the right time. It was kind of gusty outside maybe 30 degrees. now way I could reach the air intake with the stove hot. Don’t want to create an explosion by sealing it all the way off either.

I’m glad I had the big blower. I use it less than 1/2 the time.

Drolet does offer a blower and thermodisc setup but I was hoping to avoid any electronics for power outages...as well as the blower noise. Obviously don't want to burn my house down either.

 

[begreen]

Overheating is more likely to have occurred due to operator error, not with the stove in a fireplace.

The Drolet can operate without the blower during an outage. And the blower can be run on low speed to keep the noise low. When it is zero outside the blower will be welcome.

 

[faultymechanics]

Overheating is more likely to have occurred due to operator error, not with the stove in a fireplace.

The Drolet can operate without the blower during an outage. And the blower can be run on low speed to keep the noise low. When it is zero outside the blower will be welcome.

All sounds reasonable. For $150, blower seems like good insurance.

 

[EbS-P]

couple larger and smaller stoves I've seen have "installed in fireplace" instructions (mainly jotul).

I will add since you have an exterior chimney you will loose considerable heat through the brick which if you went insert you could insulate and then cover up with the surround. Not planning on heating full time it’s probably not a big consideration. With my radiant stove 90 degrees on the wall behind the chimney is normal after running for 12 hours.

 

[faultymechanics]

I will add since you have an exterior chimney you will loose considerable heat through the brick which if you went insert you could insulate and then cover up with the surround. Not planning on heating full time it’s probably not a big consideration. With my radiant stove 90 degrees on the wall behind the chimney is normal after running for 12 hours.

Haha, this certainly won’t be an efficient endeavor. That’s okay though.
I was told to run a block off plate to help with heat loss which I will definitely do. The opening up the flue of the chimney is absolutely massive.

 

[begreen]

All sounds reasonable. For $150, blower seems like good insurance.

Why put a freestander in there instead of an insert with a full convection jacket and blower included?

 

[bholler]

I don't think there is a big danger of overheating due to simply being inside the firebox. But it is going to be the least efficent spot to install a stove

 

[faultymechanics]

I haven’t found any inserts that only require ember protection. I could take on a project and try to redo the hearth extension but it’s then likely to stand another 1/4 higher.
I also have so many other projects I’m doing in the house.

If I can avoid another I might try to. I can do it if I must.

I’ve found several freestanding stoves that will fit with about 2.5” poking out; they only require ember protection which I have.

 

[EbS-P]

I haven’t found any inserts that only require ember protection. I could take on a project and try to redo the hearth extension but it’s then likely to stand another 1/4 higher.
I also have so many other projects I’m doing in the house.

If I can avoid another I might try to. I can do it if I must.

I’ve found several freestanding stoves that will fit with about 2.5” poking out; they only require ember protection which I have.

I like the look of the stove tucked in the opening. I might even leave the surround off my insert but we will see. i think that the stove over insert to not have to modify hearth is a fine choice. I’d make a similar one. We all make compromises.

 

[faultymechanics]

Hey all, bumping this thread for some new questions.

We got a second quote from the only other game in town and they said we can't put an insert in our fireplace because it looks like the wood form and floor joists are under our hearth.

Now, to me, it looks like the form is only there under the hearth extension. However, I haven't seen in any manual where it says you can't have wood(or a combustible material) under your hearth slab (Directly under where the wood insert sits).

Is this true? Do I need a high R value directly under the wood insert as well?

My quotes for a new freestanding stove was 7.6k with a new liner and my quote for an insert with reline from another company was 6.6k.


Suggestions? Thoughts? Is an insert okay to put in there (disregard hearth extension for the purpose of this question)?

Or should I pull out the current busted insert, pull up the hearth extension tile and lay down 1" of Micore?

Guidance would be more than welcomed.

 

[begreen]

What does the insert manual say is required for the hearth insulation value? R=1.0 is not untypical.

How hard would it be to remove the wood form support underneath the hearth?

 

[faultymechanics]

What does the insert manual say is required for the hearth insulation value? R=1.0 is not untypical.

How hard would it be to remove the wood form support underneath the hearth?

Hmm, the floor protection for the osburn 2000 insert doesn't seem to say an insulation value, EXCEPT for the extension. Maybe I'm missing something?

I'll take some photos this afternoon and post below but I know there are floor joists which can't be removed, although those aren't directly below, there is an airgap for those. The Hearth and extension is arched and I'm not sure if it is structurally important? As I said I'll post some photos so I can get some input here. Of course, if I do go that direction I will have a contractor confirm.

 

[begreen]

That's correct. The manual and I are assuming that the fireplace itself has a full masonry foundation. Is this what is there? If the hearth extension is at the same height as the fireplace floor then the extension requires an R=1.0 rating. This could be accomplished with a hearth extension board.

We like pictures if you can post some of the fireplace, the hearth and the underside area of concern.

 

[EbS-P]

So the combustibles under the hearth extension means it (the masonry fireplace hearth unit) doesn’t meet code. All the manuals say inserts can only be installed in a code compliant fireplace. That’s the code, no grey area from a code standpoint.

Now if you put a stove in there that only needs ember protection and can verify all clearances to combustibles, I think that’s a grey area. That stove doesn’t need anything more than ember protection. Over a combustible floor.

Adding an insulated pad under the entire insert going into the firebox and extending out front you might be able to get a variance granted for that but I really have no clue.

Do I personally think an insert installed in a masonry fireplace where combustibles touch the hearth extension is safe? Probably. I know it’s safer than burning the open fireplace. I have combustibles touching the sides of my concrete hearth extension and I am not worried one bit.

Furthermore after installing my Drolet insert and seeing how the combustion air moves and the convection air moves under the firebox I would be even less concerned.

Does any of this change code? Not one bit. Can you make it safer than it was? yes.

 

[faultymechanics]

Pasting photos below. Pardon the severed dog toys on the hearth extension. My dog is a monster.

Under that I will put a youtube link to a video I recorded of the basement and the form. That may be a clearer video.



Link to the video I made: Hearth Video

 

[bholler]

Pasting photos below. Pardon the severed dog toys on the hearth extension. My dog is a monster.

Under that I will put a youtube link to a video I recorded of the basement and the form. That may be a clearer video.

View attachment 285813View attachment 285814View attachment 285815View attachment 285816View attachment 285817View attachment 285818View attachment 285819View attachment 285820View attachment 285821


Link to the video I made: Hearth Video

Just cut the wood out

 

[begreen]

How far in front of the insert door does the hearth extend?

 

[faultymechanics]

How far in front of the insert door does the hearth extend?

I believe for the current door it's 16". The full length of the extension is 18.75"

 

[bigealta]

If you do put in a freestanding stove a small fan just on the floor works great at blowing out the hot air. Raises house temps in my house by a number of degrees. Also with this stove the bricks under the stove barely get warm. Even without a fan and burning 24/7.