New home with open fireplace fire alarms

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Holden

New Member
Nov 4, 2017
30
Indianapolis
We recently moved into our new home and have now had our third fire. Last night, our fire alarms went off because of the smoke. It happened again tonight. What in the heck is wrong? The flue is open all the way. We had wood delivered and at first I thought that the wood may not have been seasoned enough. I went and bought one of those little packages at the gas station and the same damn thing keeps happening. Any thoughts?
 
Was the chimney cleaned and inspected before the first fire? Could be any number of things from birds or bees nest, dirty flue, stuck damper, etc..
 
Also the wood from the gas station is no more seasoned then any wood your buying....... Another words its all wet wood for the most part.
 
Well it's a brand new home, so we didn't think it would be necessary, so no.
Ah, that helps to know. Is this a full masonry fireplace or a zero-clearance fireplace? If ZC, it might be paint baking in. This can happen with the first few hot fires. If this is the case, open a couple windows while burning. If the smoke doesn't get better then it's time to call the contractor in to make sure something isn't wrong. If this is a masonry chimney, can you look up past the damper and see daylight?
 
Ah, that helps to know. Is this a full masonry fireplace or a zero-clearance fireplace? If ZC, it might be paint baking in. This can happen with the first few hot fires. If this is the case, open a couple windows while burning. If the smoke doesn't get better then it's time to call the contractor in to make sure something isn't wrong. If this is a masonry chimney, can you look up past the damper and see daylight?

It is a masonry fireplace. We will check for daylight tonight when we get home.
 

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It is a masonry fireplace. We will check for daylight tonight when we get home.
It should not be setting off the smoke detectors. There may not be a simple answer. Does this only happen on startup? If so, the chimney may be cold. Make sure that the damper is opening fully and the wood is seasoned. There are some physical possibilities like the flue size being too small, or the opening height being too high. You can check both of these by measuring the fireplace opening size and the chimney flue liner size. As a temporary test you could tape some aluminum foil so that it drops down the opening height by 4-5" and see it that makes a major improvement.
 
I meant "tonight" as when I get home from work, smarty pants. I saw daylight all the way up, it looked totally clear.
There are tons of variables that can cause this. Can you try opening a window near the fireplace next time to see if that fixes the problem?
 
It should not be setting off the smoke detectors. There may not be a simple answer. Does this only happen on startup? If so, the chimney may be cold. Make sure that the damper is opening fully and the wood is seasoned. There are some physical possibilities like the flue size being too small, or the opening height being too high. You can check both of these by measuring the fireplace opening size and the chimney flue liner size. As a temporary test you could tape some aluminum foil so that it drops down the opening height by 4-5" and see it that makes a major improvement.

It does not only do this on start up, last night it took about a hour or so before the smoke started to accumulate in the house. I also notice it when I add a piece of wood to the fire and/or stir up the wood that is in the fire. I will track down some 100% seasoned wood from a friend. Could you try and explain the aluminum foil test a bit better? 34w x28h x19d is the size of the fireplace opening. my husband will have to get on top of the chimney to see the size of the flue liner, we can't get to it from the inside. do most flue's these days open by pushing up? Our house growing up had one that pulled down.
 
It does not only do this on start up, last night it took about a hour or so before the smoke started to accumulate in the house. I also notice it when I add a piece of wood to the fire and/or stir up the wood that is in the fire. I will track down some 100% seasoned wood from a friend. Could you try and explain the aluminum foil test a bit better? 34w x28h x19d is the size of the fireplace opening. my husband will have to get on top of the chimney to see the size of the flue liner, we can't get to it from the inside. do most flue's these days open by pushing up? Our house growing up had one that pulled down.
The foil thing will tell us if it is a problem with the fireplace design either because the ratio between the liner and firebox opening are off or the damper is not high enough above the top of the opening.
 
Not sure how your flue damper control works. It's best to look up into the chimney and see which way opens it up fully.
 
Not sure how your flue damper control works. It's best to look up into the chimney and see which way opens it up fully.

We can only push the damper up, not down. Silly question, is there a youtube video that shows what you mean to do with the tinfoil? I'm not sure that I'm following.
 
There are tons of variables that can cause this. Can you try opening a window near the fireplace next time to see if that fixes the problem?
so, I'm not trying to be a smarty pants here, but what is that going to do? or what would that tell you? Of course it's going to help keep the detectors from going off in the house if the smoke is going out the windows. Again, not trying to be a smarty pants, just trying to understand your thought process.
 
Probably not. It is just for testing. Take a roll of tin foil and tape it so that about 5" hangs down in front of the fireplace opening, all the way across. This will effectively reduce the fireplace opening from the current 28" high to 23" high.

so, I'm not trying to be a smarty pants here, but what is that going to do? or what would that tell you? Of course it's going to help keep the detectors from going off in the house if the smoke is going out the windows. Again, not trying to be a smarty pants, just trying to understand your thought process.
That is a check to see if there is negative pressure in the house. Modern construction is often very tight. If so, or if there is an HRV system or an exhaust fan running in the house it could be causing negative pressure.
 
Probably not. It is just for testing. Take a roll of tin foil and tape it so that about 5" hangs down in front of the fireplace opening, all the way across. This will effectively reduce the fireplace opening from the current 28" high to 23" high.


That is a check to see if there is negative pressure in the house. Modern construction is often very tight. If so, or if there is an HRV system or an exhaust fan running in the house it could be causing negative pressure.

ok, that makes sense now with the tinfoil, thank you! So if we find this solves the smoke issue, what does that mean? We are fireplace virgins. Do any of you have fireplaces without doors? I was hoping to keep it open for looks, but we may need doors??
 
ok, that makes sense now with the tinfoil, thank you! So if we find this solves the smoke issue, what does that mean? We are fireplace virgins. Do any of you have fireplaces without doors? I was hoping to keep it open for looks, but we may need doors??
If any of these things fix it it will tell you what the problem is. You can then go to your builder as nd make them fix it.
 
Opening the windows tells you if your problem is with air intake to the fireplace. A tight home might not let enough air in, so it limits your exhaust. Same thing if you have other exhausting appliances (water heater, dryer, bathroom fans, etc) running at the same time.
 
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So I moved into a home that had a beautiful fire place. The first thing I did was buy a bunch of wood. The home was built in 1989, the fire place seems to be used only like a half dozen times. Well, I made my first fire and smoke came in my home (a lot of smoke, unlike you which you get a little smoke). First thing I did was open up windows, and this seemed to solve the draft problem but did not make sense regarding having a fire in the winter with windows opened. Well... it has been FIVE years and we have not made a fire but this year (actually in 2 weeks), I will be installing a Wood Insert into the fire place and this is suppose to solve the problem. It is costly... about $6.8K but will save you money in heating (still hard to justify)... BUT I will be able to have a fire!!!!

There are fixes to a draft fireplace, but the reality is that it is a HARD issue to fix unless you go with the inset way. I have heard of putting in fresh air vent in your fire place, fans (that people don't really like), cleaning your chimney, etc... Do you have kids? Asma? Cause having soot in the air (even it your fire alarms do not go off)… is not good for long term breathing problems. Almost any fix will cost you $$$$ and there is no guarantee.

An open fire place makes you LOSE heat, while a insert is like having a second furnace. I know of people who spent like $$$$ on glass doors for their fireplace, again I would rather pay $$$ and get an insert.

Lastly, you have new construction… you may be able to go after the seller about correcting your problem, but again, like I said before it is hard to correct a negative draft issue (but possible)