Fireplace safe to burn?

[cabinwarmer]

Hello All, I am starting a new pst to gather any input on still being able to burn my current fireplace. I have had it inspected by a Sweep, and his report reflects a rusty firebox and mortar missing from the flue tiles. There is also a recommendation to remove the current rusted damper (shelf) and instal a top damper. That is fine with me. What I am struggling with is this is a complete granite stone fireplace and chimney. I understand there is a need for improvement, and I would like to do what I can (install top damper, mortar any loose spots I can reach, etc). Even in this condition, what exactly is the fire risk? There is nothing combustable. What am I missing. Thanks in advance for your feedback.

Dave

 

[jatoxico]

Without pictures and a detailed discussion its not going to be easy to answer your question. One thing I've heard here and I would say is a good way to approach the situation is to think will it still be safe in the event of a chimney fire, You have to prepare for the worst case scenario.

 

[cabinwarmer]

I tried to load the pictures. They are in the report that is a pdf file. This site will not let me load them. I understand your comment. I guess I do not see how a chimney fire would even begin. I will try to manipulate the pictures again. Thanks!

 

[jatoxico]

I tried to load the pictures. They are in the report that is a pdf file. This site will not let me load them. I understand your comment. I guess I do not see how a chimney fire would even begin. I will try to manipulate the pictures again. Thanks!

Yeah post up the pics. As far as chimney fires go it's mainly due to creosote as far as I know but its enough for me to know that they can and do occur. If there's missing mortar between the clay tile etc. then it would be that much more of a concern. It's hard to imagine how you could adequately repair that in place although I did see a technique on a recent TOH where they pulled a plug through forcing mortar into the cracks.

What is your goal with this, just open fires for ambiance?

 

[Ctwoodtick]

Hello All, I am starting a new pst to gather any input on still being able to burn my current fireplace. I have had it inspected by a Sweep, and his report reflects a rusty firebox and mortar missing from the flue tiles. There is also a recommendation to remove the current rusted damper (shelf) and instal a top damper. That is fine with me. What I am struggling with is this is a complete granite stone fireplace and chimney. I understand there is a need for improvement, and I would like what exactly is the fire risk? There is nothing combustable. What am I missing. Thanks in advance for your feedback.

Dave

I’m sure the pros on here will chime in but in my layperson thought, missing mortar in between the flue tiles could let smoke in back of the tiles and build up. If that buildup ignited that would be a big problem. I’m not sure about the rusty firebox thing. If you’re going to use the fireplace, I would think having it relined with stainless steel insulated liner would be smart.

 

[coaly]

If you have glass doors that slows the air flow, unlike a wide open hearth opening, any joints in the flue liner can allow cooler air into the chimney. This cools the exhaust gasses allowing the water vapor from combustion to condense on flue walls forming creosote. It also slows the draft by cooling the rising gasses causing other problems. An open fireplace loses most of the heat directly up the chimney staying clean, but very inefficient for heating. When you add doors with an air control, it slows the fire and you have to be sure to leave enough heat up the chimney to keep it clean. It needs to stay above 250*f to the top to prevent creosote formation. Fireplaces generally allow plenty of heat up, when an Insert is installed or stove connected that has controlled combustion, this becomes critical since the Insert extracts the heat leaving much less to keep the chimney clean.

Any holes through the firebox allows air to rush in feeding the fire. (with glass closed fireplace face and controlled air intake) Good for keeping the stack clean, but will burn harder and faster than you want wasting fuel. The reason air leaks in, and not smoke out is because hot rising gasses in the flue create a low pressure area in chimney and firebox allowing atmospheric air pressure to push air into the fireplace opening / firebox filling the void created by chimney. In the firebox this feeds the fire oxygen. Cracks between flue tiles allows the higher air pressure from outside the chimney in, cooling the flue. In an extreme case you will have smoke build at the top of firebox and roll in like a flue damper is closed too far since this cool air slows draft. It's not always a safety issue as directly catching fire, it's a safety issue forming creosote which catches fire in the flue dropping hot embers on the roof.

 

[cabinwarmer]

Thanks for the quick reply's! Jatoxico, the purpose for this conversation is an open fire for ambiance, yes. I am also looking at all the options as well....CTwoodtick, smoke behind the tiles is something I did not think of. My options on "fixing" the fireplace are still not clear to me. Sounds like possibly a new firebox - one slightly smaller then what is in there now, or removing the original one. And, adding a 100% new lining. I did not know you could add linings. The flue is extra large, so I think that might not be too difficult. The firebox is also rather large, the opening is 50inch wide. Let me try to work on the pics tonight. I may have to post the entire report, which is what I am trying not to do.

 

[bholler]

Thanks for the quick reply's! Jatoxico, the purpose for this conversation is an open fire for ambiance, yes. I am also looking at all the options as well....CTwoodtick, smoke behind the tiles is something I did not think of. My options on "fixing" the fireplace are still not clear to me. Sounds like possibly a new firebox - one slightly smaller then what is in there now, or removing the original one. And, adding a 100% new lining. I did not know you could add linings. The flue is extra large, so I think that might not be too difficult. The firebox is also rather large, the opening is 50inch wide. Let me try to work on the pics tonight. I may have to post the entire report, which is what I am trying not to do.

If your damper is rusted out your smoke shelf and smoke chamber certainly is. The mortar joints are the least of your problems. Smoke leaking into the convective chamber can easily lead to CO in the home it is unusable. You either need an insert or cut out the metal box build a masonry one and line the chimney.

You should have had a chimney inspection

 

[cabinwarmer]

Thanks Coaly - I get it... very good feedback. bholler......my report was from a sweep/inspection. My issue is I was not offered any repair advice or guidance. The sweep just said 10K to fix. (right....) So I am trying to understand if I have any options to repair. Might still go with a stove or insert.

 

[bholler]

Thanks Coaly - I get it... very good feedback. bholler......my report was from a sweep/inspection. My issue is I was not offered any repair advice or guidance. The sweep just said 10K to fix. (right....) So I am trying to understand if I have any options to repair. Might still go with a stove or insert.

10 k is in the right ballpark

 

[cabinwarmer]

Oh boy..........

 

[bholler]

Oh boy..........

An insert and liner would be cheaper

 

[RobbieB]

And better, much better -

 

[cabinwarmer]

Yep........thanks again!

 

[EJL923]

I understand the open fireplace thing, but IMO it is easy to get over. if you will be burning regularly, the efficiency alone of an insert will put a smile on your face. A nice insert will pop off that stone fireplace, and the dancing flames will still be present. the snap crackle pop will not be missed, again IMO. No smoke smell.

 

[Ctwoodtick]

I understand the open fireplace thing, but IMO it is easy to get over. if you will be burning regularly, the efficiency alone of an insert will put a smile on your face. A nice insert will pop off that stone fireplace, and the dancing flames will still be present. the snap crackle pop will not be missed, again IMO. No smoke smell.

Totally, not to mention having an open fireplace going keeps you busy when you just want to chill out. The wood burns quick and then you have to tend to. With in insert, you won’t have to mess with it after reloading for hours.