Fireplace Xtrodinare Insulation of Chimney

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jim1959

New Member
Jan 3, 2019
5
Charleston
After installing the 44 elite; I have problems with sufficient draft and smoke entering the room. The local installer suggested insulation of the walls of the chimney system (chase). However, the elite has a cooling duct system that draws cold air from the outside and circulates it within the walls of the unit and up within the chimney's triple wall flu. The idea being the unit would get too hot near combustible material if not cooled with outside air. I'm asking then... does it make since to insulate the walls of the chimney system (chase) when the unit itself seems to be fighting overheating? Note, I working off logic, perhaps there is more to the story?
 
How tall is the chimney and is it within the stated spec? Where is the unit installed, first floor or basement of a multi-story home?
 
The chimney is 15 feet, everything is within installation specs, however chimney height is at the exact factory minimum. The fireplace is on the first floor of a one story house.I suspect adding a few feet to the chase and piping would help; perhaps even solve the problem. It will make for a "tower" like chase that is a bit gaudy; but I use the fire place all winter so functionality trumps street appeal. The salesman perspective was the cold air around the flu negatively effects draw. True? But Travis Industries requires a cold air to circulate through the space in walls to maintain zero clearance status; so I'm not understanding the value of insulating the wooden box. For that matter does insulation the chase make a difference?
 
The chase doesn’t need insulated, although you need an insulated draft stop. At ceiling level above the fireplace, is there a solid plywood top that the chimney penetrates? If so, is it insulated?
Where do the cooling vents terminate? I hope you are on an outside wall, otherwise it’s hard to properly vent these units.

When are you getting the smoke in the room?
 
Can you provide some pics or describe the problem and how and when it is occurring , you stated what the local installer suggested and I think what the manufacturer suggested . But it’s not clear if you have or have not insulated
 
The unit is "attached" to an exterior wall, sitting on its on foundation. Nothing passes through the ceiling. If you are looking up the chase from the top of the fireplace unit, it just one big tall wood box around the flu, capped at the top with a metal cover which the chimney pipe passes through. Almost as if the fireplace is "outside the house; but the face is flush with the wall of the room it heats. The two intakes for cooling are cut through the walls of the chase, drawing cold outside air. So the unit and all piping is surrounded by cold,air, without benefit of any insulation. You can't open the doors without smoking up the room. It is impossible to load wood without smoke billowing out. Does the temperature around the chimney pipe effect draw? Could it be too cold when you combine the cooling duct effect with the fact that most of the fireplace is actually in unheated - un-insulated space?

I will get some pics... they are worth a thousand word!
 
Sounds like you’ve got some issues that weren’t addressed.
The cantilevered chase itself needs insulated on the outside walls. It’s still part of the house... The chase should have a solid ceiling even with the ceiling of the adjacent room, this acts as a draft stop, it gets insulated on the top side just like your attic.
Many builders don’t get this for some reason, sometimes we end up doing the insulation just becuase we know it won’t get done by anyone else. We almost always build the draft stop. Even though it’s really the builders responsibility.
 
Another thought. Is the blower installed on an outside wall pulling fresh air from outside?
 
Jim as webby has suggested it seems you have a few issues affecting your stove , 1st off a cold area surrounding an insulated stove pipe will have no effect on chimney draft ( this being said you having the absolute minimum chimney height means if outdoor temps are not 30* or lower you may have difficulty starting good draft . Is the 15’ chimney height measured from the stove outlet or from the ground outside ? If so what is the difference?
 
How long have you been burning? These caps have a tendency to clog up pretty quickly, can you see the cap? I assume so at only 15’! That minimum height given is in ideal circumstances, other things in play may make it necessary to extend the flue. You can do that without extending the chase.
 
The smoke billowing into room sound like a negative pressure issue , be sure any exhaust fans are turned off , kitchen vent, bathroom, any type of air handler , try opening a window than open stove doors no smoke = not enough make up air to feed flue , or suction from an appliance reversing draft pulling smoke into room .
 
1st off a cold area surrounding an insulated stove pipe will have no effect on chimney draft ( this being said you having the absolute minimum chimney
This particular system doesn’t use insulated pipe unfortunately. It’s double wall air cooled pipe. The entire jacket of the fireplace is connected to 2 cooling vents that allow cold air to circulate throughout the jacket as well as the cooling wall of the chimney. The blower uses cold air from outside of the home to create a positive pressure system. It’s a very detailed system that many installers screw up. The missing insulation may or may not be causing the issues. Either way, it’s not correct and will always cause air infiltration and condensation.
That chase cover will be dripping like a rainforest back there with no draft stop or insulation!
 
This particular system doesn’t use insulated pipe unfortunately. It’s double wall air cooled pipe. The entire jacket of the fireplace is connected to 2 cooling vents that allow cold air to circulate throughout the jacket as well as the cooling wall of the chimney. The blower uses cold air from outside of the home to create a positive pressure system. It’s a very detailed system that many installers screw up. The missing insulation may or may not be causing the issues. Either way, it’s not correct and will always cause air infiltration and condensation.
That chase cover will be dripping like a rainforest back there with no draft stop or insulation!
I’m confused I thought with triple wall the outer most ring was the one to carry fresh air
 
The OP did describe it as triple wall. You may be right, but he also might know something different about his set-up.
Everybody calls it triple wall... I’ve installed a few dozen of these Elite units. They did allow a few different pipe brands to be used, all were double wall to my knowledge. For the last several years they have their own pipe that’s made by Dura-Vent. Also double wall.
 
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The fireplace is being reconstructed as indicated by pics. Hurricane damage. The outside provides more clarity on the concept of cantilevered. The fireplace front was all destroyed by "recovery team". All cooling duct work and blower has been removed, but it was all there once upon a time along with a beautiful mantle. (The blower shuts off when the fire place doors are open). The entire unit will be replaced with another 44 elite, so now is the time to get it right. It has never drawn correctly since day one of use.
The picture up the chase is the way it has always been. No insulation and no ceiling.
So from this thread... I need a ceiling in the chase at room level if for no other reason than it is technically part of the house and subject to air infiltration. Logical. I need a ceiling and insulation to prevent condensation, which might explain the extreme moisture issues that had nothing to do with a hurricane. In fact I am rebuilding the entire chase as you can see from the outside photo, much of the OBX board was rotted. I just wish I had insulated it before I enclosed it with plywood. I can still add the ceiling and insulate the lower part, but climbing way up into the chase with insulation might be out of my skill level and I am still unsure with a system built to flush fresh air around the pipe that it would matter with draw. I can frame up an extra 2-3 feet since the cover is being replaced and new piping will be installed. It is now exactly 15 feet from the pipe that extends above the cover at the top to the damper door within the unit. My last question... would an additional 3 feet make enough difference to justify the effort? Thank you all.
 

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Why weren’t you honest about the situation from the start? It would have eliminated a lot of post trying to diagnose the smoke issues.

Yes, 3’ would make a difference if the minimum height chimney was the contributing factor.
The draft stop is actually a code requirement, not sure how they got that past the inspector, it happens too often really. It does more than prevent air infiltration. In the event of a fire in the chase, the chase will act as a big chimney sucking the fire up into the roof system of your house, with the draft stop it can’t get enough air to become as big of a fire so quickly.

The cap that up there now looks square, is that the cap I’m seeing?
 
Glad for the pics , the extra 3’ of pipe can only help the draft of the stove .hopefully your new installation team will do the right job keep us posted after completed
 
Glad for the pics , the extra 3’ of pipe can only help the draft of the stove .hopefully your new installation team will do the right job keep us posted after completed
In reality, it was the builder that dropped the ball. The installer should have insisted it be done though.
 
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In all honesty I had envisioned the cantilevered fire place and chase exactly as is from his description , as far as the entire stove face missing and the inner wall missing I had no clue
 
Not sure what in my initial inquiry was dishonest? My original unit smoked up the house as will the new one unless corrective measures are taken. Hopefully I can apply the info gained here and correct the deficiencies. Since installers do not bang nails and nail bangers (me in this case) know nothing about draw, then no one takes credit or blame when it doesn’t work as advertised.The information given has been helpful. Interesting the new installer never mentioned a ceiling, only told me to insulate the chase to the top. If it’s code, then I’m now 0 and 2 on Travis industry dealers/representatives and got more accurate info on a web site for free. I value the responses and apologize if it appeared to waste time.
 
Will you also be replacing the pipe? It would be a great time to upgrade to the current pipe.
 
Not sure what in my initial inquiry was dishonest? My original unit smoked up the house as will the new one unless corrective measures are taken. Hopefully I can apply the info gained here and correct the deficiencies. Since installers do not bang nails and nail bangers (me in this case) know nothing about draw, then no one takes credit or blame when it doesn’t work as advertised.The information given has been helpful. Interesting the new installer never mentioned a ceiling, only told me to insulate the chase to the top. If it’s code, then I’m now 0 and 2 on Travis industry dealers/representatives and got more accurate info on a web site for free. I value the responses and apologize if it appeared to waste time.
A draft stop is standard practice. Think of that chase from the ceiling down as a part of the house. No different than a cantilevered closed would be. Could you imagine not insulating or having a ceiling in a closet that was cantilevered?