Fireplace Insert that works well when power is out, and has good outside air system?

[ColdStove]

Hi all, we have a big masonry fireplace that we're looking to fill with a wood burning insert, ideally one with an outside air system, and which still puts out good heat when the power is out. This is partly to solve an issue with negative pressure in the house pulling air down the chimney and into the living space, giving a pretty strong creosote smell, so we'd really like to replace this with something well sealed off from the living space, so that it just puts out heat.

I was looking at the Pacific Energy Summit LE insert, which people seem to have generally positive things to say about around here, but when I contacted some installers, they seemed to say that they don't really do outside air setups with it. And then some posts on here that seemed to indicate it can have outside air vented to the ash box, but that it's not really sealed off from the room air.

The fireplace opening is 34.5" wide, 30" tall, 25" deep at bottom, 20" deep at top, the back is 28" wide at bottom and top.

Does anyone have a recommendation for a great stove that might fit our needs? Maybe a Hearthstone? Though I've seen mixed things about them on here.

Our house is about 3000 sqf conditioned.

Thanks very much for any help.

 

[begreen]

There is no ashpan system on the Summit insert. On the Summit freestanding stove, the OAK is intentionally decoupled from the air intake to avoid siphoning smoke through the OAK. The Summit insert has the option for outside air. Most installers will not do this because it is a hassle to retrofit and a time sink. Some fireplaces have outside air already piped into them. Others may have an exterior ash cleanout that may be screened and adapted to supply outside air. The Regency i2450 is also worth looking at. It extends out onto the hearth a bit. So does the Osburn 3500-i.

 

[mellow]

If you are installing an insert with an insulated liner and an insulated block off plate and fireplace do you really need an OAK? Is your house that tight? Do you have an HRV/ERV system?

 

[ColdStove]

Thanks for the replies!

mellow, we did recently get an ERV installed, and we're in the process of sealing the various gaps, especially the attic. I don't really know how tight the house will get, but OAK seemed like a good idea given the negative pressure problems we've been having, but maybe I need to reevaluate if it's uncommon/hard to get done.

begreen, ah I see, I might've gotten confused and read a comment on here about the Summit freestanding rather than the insert (I think it might've actually been one of yours). Our fireplace doesn't currently have outside air piped in, it's a pretty simple brick fireplace.

I'm getting the sense that maybe OAKs are rarely installed for inserts, would that be fair to say?

 

[ColdStove]

Oh, and I didn't realize that an insulated block off plate was something I should be asking for, thanks!

 

[begreen]

Yes, outside air for a fireplace is not all that common especially in basement fireplaces.

 

[ColdStove]

It's ground floor, and should be pretty easy to get outside (the fireplace on an exterior wall, cinderblock behind the brick), but good to know.

 

[begreen]

To add outside air it would take knocking a 3.5" hole down low at the back of the fireplace and cementing in a 3" duct with a rain hood and rodent screen on the outside.

 

[ColdStove]

Hm I wonder if it's feasible for me to DIY with next to no masonry work experience, maybe I'll take a stab at it if none of the installers are willing to do it. Thanks again for the help.

If anyone reading this knows of any inserts that work really well with outside air, please comment!

 

[ColdStove]

Looks like Osburn makes a sealing air intake damper: https://www.fireplacesdirect.com/os...ke-register-with-airtight-damper-5-inch.html#

Seems a bit pricey, but good sign that they're prioritizing it, I'll take a closer look at the Osburn 3500-i that you mentioned. Are they pretty good inserts?

 

[mellow]

You will see OAK's done in mobile home installs since it is code, most stoves will have a knockout in the air supply to add an OAK to it, its really a simple process, much like installing a dryer vent.

If your house is really tight (like it sounds) you might benefit from an insert that can burn low and slow like the Blaze Kings, I would check them out as well.

 

[ColdStove]

You will see OAK's done in mobile home installs since it is code, most stoves will have a knockout in the air supply to add an OAK to it, its really a simple process, much like installing a dryer vent.

If your house is really tight (like it sounds) you might benefit from an insert that can burn low and slow like the Blaze Kings, I would check them out as well.

I’ve been looking at the Blaze King Princess 29 insert, it generally sounds great, but I was having a hard time finding any mention of outside/fresh air in the manual. I think the stove version has it, but I think the insert might’ve been left out of the fun :-(

Thanks for the link to your fireplace insulation, btw, it made me realize I really need to do something like that here, since the backside of it is basically outside, and gets hot when we have a fire in it. Glad I saw that before we put a 500 pound chunk of metal in there

 

[mellow]

You know what, I thought it had a knockout on the side but then I remembered it pulls air from the front where the tstat is on the ashford/sirocco inserts. Not sure if you could improvise something to bring fresh air to that or not from underneath in the crawlspace, I know the freestand ones have an OAK connect. Maybe @BKVP might have an idea.

 

[BKVP]

You know what, I thought it had a knockout on the side but then I remembered it pulls air from the front where the tstat is on the ashford/sirocco inserts. Not sure if you could improvise something to bring fresh air to that or not from underneath in the crawlspace, I know the freestand ones have an OAK connect. Maybe @BKVP might have an idea.

Sorry, traveling every day for next few months. No OAK accommodations for any of our inserts or Boxer 24. All others, yes.

Thanks
Chris

 

[ColdStove]

Thanks

Sorry, traveling every day for next few months. No OAK accommodations for any of our inserts or Boxer 24. All others, yes.

Thanks
Chris

Thanks for chiming in! Ah well, I really like your inserts, otherwise.

 

[jaredledvina]

@ColdStove - I'm curious if you ever found a stove that fit your needs here. I'm in a similar position w/ a similar sized fireplace and am struggling to find a good option.

 

[begreen]

@ColdStove - I'm curious if you ever found a stove that fit your needs here. I'm in a similar position w/ a similar sized fireplace and am struggling to find a good option.

Is an OAK needed? For a thorough response, we need to know the dimensions of the fireplace, details about the area where the insert is heating, the height of the chimney, etc. Maybe start a new thread with these details and the desired look and options.

 

[ColdStove]

@jaredledvina We haven't, my wife sort of killed the project, since I couldn't be sure that the insert I wanted (a Blaze King Princess) would solve the creosote smell issue, even with outside air kit. The installers I spoke with weren't willing to claim that any of them would be well sealed off from the room with the door closed. In the end, I just sealed up the fireplace with trashbags and tape, and some posters over them, and that solved the problem perfectly as far as my wife was concerned. If the insert had been cheaper, then it might've gone differently, but we were getting quoted like $6k, which was hard to stomach when it might not even solve the issue.

 

[jaredledvina]

@jaredledvina We haven't, my wife sort of killed the project, since I couldn't be sure that the insert I wanted (a Blaze King Princess) would solve the creosote smell issue, even with outside air kit. The installers I spoke with weren't willing to claim that any of them would be well sealed off from the room with the door closed. In the end, I just sealed up the fireplace with trashbags and tape, and some posters over them, and that solved the problem perfectly as far as my wife was concerned. If the insert had been cheaper, then it might've gone differently, but we were getting quoted like $6k, which was hard to stomach when it might not even solve the issue.

Ah bummer, well thanks for following up!

I'll kick off a new thread with where we are at and looking for.

 

[BKVP]

@jaredledvina We haven't, my wife sort of killed the project, since I couldn't be sure that the insert I wanted (a Blaze King Princess) would solve the creosote smell issue, even with outside air kit. The installers I spoke with weren't willing to claim that any of them would be well sealed off from the room with the door closed. In the end, I just sealed up the fireplace with trashbags and tape, and some posters over them, and that solved the problem perfectly as far as my wife was concerned. If the insert had been cheaper, then it might've gone differently, but we were getting quoted like $6k, which was hard to stomach when it might not even solve the issue.

So did the creosote smell occur at all times or just during high winds, depressions, etc? Did you smell the creosote as well? Many retailers report that women often can smell smoke or creosote at much lower levels than male customers. There is probably some science to back this up.

There are situations where appliances, such as bathroom fans, down draft kitchen appliances and others causes reverse what should be a natural draft up the chimney. You probably made the best decision given the situation.

BKVP

 

[ColdStove]

I'm at a loss as to what causes it. The trashbag makes it pretty clear that sometimes we're seeing gusts down the chimney, as it puffs out rapidly, and then usually back in in short order. I tested whether it was due to mechanical ventilation, but I couldn't force it to happen with dryer, kitchen hood fan, bathroom fans, etc, so I don't think it's due to excessive air tightness. Perhaps there's something about the shape at the top of the chimney that diverts air down sometimes, depending on what the wind is doing?

 

[ColdStove]

I think the ultimate solution would be an insert/liner as well as a top cap damper to seal off the top of the chimney, but the installers said that it had to be one or the other. Have you all ever heard of both coexisting?

 

[begreen]

I'm at a loss as to what causes it. The trashbag makes it pretty clear that sometimes we're seeing gusts down the chimney, as it puffs out rapidly, and then usually back in in short order. I tested whether it was due to mechanical ventilation, but I couldn't force it to happen with dryer, kitchen hood fan, bathroom fans, etc, so I don't think it's due to excessive air tightness. Perhaps there's something about the shape at the top of the chimney that diverts air down sometimes, depending on what the wind is doing?

There are a number of factors that can cause this including the chimney location in relation to the roofline, the house location, and local terrain.

A non-commercial service in support of responsible home heating with wood - How Wind Affects Chimney Performance

The Wood Heat Organization was formed to support the public in the responsible use of wood energy in the home. We fulfill our mandate by providing reliable information, by conducting research into wood heating-related issues and by representing the public interest in discussions of policies that...

www.woodheat.org

 

[BKVP]

I'm at a loss as to what causes it. The trashbag makes it pretty clear that sometimes we're seeing gusts down the chimney, as it puffs out rapidly, and then usually back in in short order. I tested whether it was due to mechanical ventilation, but I couldn't force it to happen with dryer, kitchen hood fan, bathroom fans, etc, so I don't think it's due to excessive air tightness. Perhaps there's something about the shape at the top of the chimney that diverts air down sometimes, depending on what the wind is doing?

I might be tempted to try an experiment. Get a metal pan made that has 6" lip all the way around. Cut a 8" hole in the center. Invert the pan and slide it over your chimney. Fasten the 6" Class A 4' section to the pan. Drop it through the hole.

Now you can observe the benefit or no benefit to increased chimney length. Watch your plastic to see if it responds differently.

BKVP