Feedback on C450 insert install

[sbeausol]

Hi Everyone-

I recently bought a house in Essex MA that is electric baseboard heat. It is a 2100 sqft range with a fireplace in the dining room and in the basement with a 15' chimney on the interior of the house. After seeing my heating bill for Oct, I decided supplemental heating would be a good idea. I was fortunate to pick up a 2006 Jotul C450 insert used for about $1500 and I am in the process of getting ready to install. From what I've read, my understanding is that a block off plate hooked up to a stainless flex pipe vented out the top of the chimney is the ideal install strategy. I'm a DIY guy, so I'm hoping to tackle this myself.

The damper in my fireplace looks like this:

The strange thing I noticed is that above the damper the chimney is stepped (I never looked up chimneys so that may not be strange). In other words, the path out of the chimney is up (obviously) and to the right as illustrated by this pic:

Basically, the chimney vents straight up from the far right of the fireplace (the pic is flipped 180 degrees). Is there any reason to believe that getting the flex pipe to make that corner will be impossible?

Thanks for any feedback!

 

[Rudyjr]

First off I would highly recomend that you have it cleaned and inspected by a chimney professional. They will tell you what kind of shape everything is in and if you need to insulate the liner. My install is in a basement masonry fireplace that is below another fireplace upstairs. There is quite a jog in my downstairs chimney and it took a bit to pull the liner past it. I would also suggest that you remove the damper and cut away part of the damper throat it makes the liner and block off installation alot easier. Pictures of my install are in my signature, good luck be safe.

 

[TTigano]

I would agree with Rudy as far as having the chimney inspected / cleaned prior to installation. If you plan on burning this year do you already have good seasoned wood? If it was me, I would insulate the liner as it isn't going to be a huge price option but should help you out. it keeps more heat in the liner which in turn can reduce creosote build up. Goodluck and please keep us posted and updated with pictures!

 

[sbeausol]

Guys-

Thanks for the feedback. I had the chimney inspected and cleaned when we bought in June. The report indicated that some of the grout on the tiles had dried out so it would be best to re-line prior to using the fireplace. Thus, I figured if I'm going to put money into it, I should just go with an insert. I will line the entire chimney. I wondered if an insulated liner would be important. I figured with an interior chimney, it wouldn't make a big difference. Am I wrong on that?

As for wood, I have access to some wood, and I have a huge amount of scrape white oak from installing hardwood throughout the house. My plan is to run evenings and weekends to cut on my electricity bill down

 

[chimneylinerjames]

Yes it is very important to insulate the liner. It will make a huge difference in the amount of creosote build up even if the chimney is in the middle of the home.

As Rudyjr said, I would also cut away the throat of the damper, not just the plate but the framing of the damper area. This will make the install of the liner much easier.

As far as the bend goes in the smoke chamber, a flexible chimney liner should have no issue making that bend at all. It does not appear to be that severe.

 

[DAKSY]

If you insulate the top couple of feet around the liner & the bottom, just above your block-off plate, that will suffice. Between the two areas of insulation you will create a standing column of "Dead Air" which will act as insulation. Insulating the entire liner probably won't gain you too much & it may make the installation of the liner more difficult.

 

[chimneylinerjames]

Since during the inspection they found some fault with the current terra cotta flue liner, to maintain the UL listing on a chimney liner for a wood stove, it needs to be insulated the entire length.

 

[DAKSY]

Since during the inspection they found some fault with the current terra cotta flue liner, to maintain the UL listing on a chimney liner for a wood stove, it needs to be insulated the entire length.

Where is THAT specified, CLJ? Not in NFPA-211, at least not that I can find...

 

[chimneylinerjames]

If I am wrong please correct me but I was reading on this page:

http://database.ul.com/cgi-bin/XYV/...n=versionless&parent_id=1073985444&sequence=1

That is the UL page for Olympia Chimney Supply, the supplier for many online suppliers. If you notice in that chart on the bottom it says insulation, "yes" for solid. The asterisk next to it then shows it is -"Optional for gas and liquid." I understand that as it is required for things as a wood stove. If it isn't installed doesn't that mean it doesn't meet their standards?

 

[DAKSY]

If I am wrong please correct me but I was reading on this page:

http://database.ul.com/cgi-bin/XYV/...n=versionless&parent_id=1073985444&sequence=1

That is the UL page for Olympia Chimney Supply, the supplier for many online suppliers. If you notice in that chart on the bottom it says insulation, "yes" for solid. The asterisk next to it then shows it is -"Optional for gas and liquid." I understand that as it is required for things as a wood stove. If it isn't installed doesn't that mean it doesn't meet their standards?

Interesting. It seems to say that you are correct, but I've never seen that on ANY liner that I've installed. Then again, I refuse buy this kind of stuff on-line, or from Big Box Stores for that matter. I prefer to go to a dedicated local hearth shop, where I know I can get a quality product & answers to my questions. I see too many people complaining about the stuff the "Get at a great Price" on-line...Anyway, If you line a perfectly good masonry chimney, that has no room for insulation, their UL listing is void? Seems that somebody jumped the gun on this one & it's a CYA stratement.

 

[Rudyjr]

Always much debate on insulated or non insulated liners on these threads. In my case my chimney was given a clean bill of health so I opted to go uninsulated. I doubt I could have gotten a liner with the standard insulation wrap around the jog in my chimney. I am not sure from the op pictures that they will be able to as well. I know there is at least one manufacturer that used to post on here that makes a liner in a liner with insulation between them, that might go. On all the ones I have done and helped with we have always done as Daksy stated earlier, Rockwool around the top under the cap and above the blockoff plate at the bottom to create a dead air space. I personally think that the blockoff plate does more to help the stove perform as intended than anything else you can do. I too believe that some of the statements that the online sellers put on their products are nothing more than CYA statements as Daksy said as well.
My chimney is on an exterior wall and my liner is uninsulated and I get less than 1/2 of a one pound coffee can of creosote when I clean my chimney every year from one and a half cord of wood. The real key to low creosote build up is SEASONED and DRY firewood. This also is the key to easy fire starting and clean glass as well.

 

[Heatsource]

some brands of flex liner do require insulation to achieve their ul listing
if the instructions say to do it, usually trumps NFPA/code
i agree it is a CYA thing

 

[Ablaze Tech]

Here is a good link on why to insulate. http://www.firesafeinc.com/products/cis . Most Liners do require insulation to meet manufacturers guidelines. Also to get a 6" insulated liner down your flue you will have to knock out your 8x12 Tiles. I do not recommend you doing this but getting a professional with the right tools and experience to knock them out. Also do not let anyone tell you they can ovalize the liner to get it down your flue. This will reduce the flow of the liner. It is like a plastic cup full of water you squeeze the cup and water pours out. To get the best performance out of the stove you need to knock out the damper, knock out the tiles, and Insulate your liner.

 

[DAKSY]

Here is a good link on why to insulate. http://www.firesafeinc.com/products/cis . Most Liners do require insulation to meet manufacturers guidelines. Also to get a 6" insulated liner down your flue you will have to knock out your 8x12 Tiles. I do not recommend you doing this but getting a professional with the right tools and experience to knock them out. Also do not let anyone tell you they can ovalize the liner to get it down your flue. This will reduce the flow of the liner. It is like a plastic cup full of water you squeeze the cup and water pours out. To get the best performance out of the stove you need to knock out the damper, knock out the tiles, and Insulate your liner.

I have to chime in on this one. I have PERSONALLY installed over 50 Wood Burning inserts & at least 20 wood burning hearthmounted stoves, most with 6" liners in 8x12 flue tile & probably 20% of them with minor ovalizing in the damper area. Never removed a SINGLE flue tile. I have removed some of the smaller damper frames- if the opening was less than 4.5 - 5"... Never got a call back on performance because of ovalizing. Never got reports from sweeps indicating that there was excessive creosote build up using only insulation below the top plate & in the damper area, EVEN on exterior chimneys... As far as insulating a full liner, I did it TWO times & both were after chimney fires & we used thermix. It was mandated by the AHJ. The only time I've dropped a fully wrapped liner is thru a 1700 degree rated flue on a ZC WB FP. In my NFI Certified opinion, leave the flue tiles as they are.

 

[sbeausol]

Guys-

I appreciate the discussion. I was up on the roof today to measure my flue and exact chimney length to make sure a 6" would fit without too much hassle. It looks like it will go, but it will be tight in a few areas. The flue is between 6.5-7" wide. As a result, I'm guessing that in order to insulate I would have to open the flue up a bit, which I would definitely prefer to avoid. I made the block off plate yesterday and following the instructions on the wiki made it pretty painless. Unless there isn't a good reason not too, I am going to pursue the rockwool approach at the top and bottom. Just need to figure out where to pick up a liner. I'm seeing prices vary wildly from $325 at chimneylinerdepot.com to $450 at some dealers in NH and $750 from a dealer in MA. Is this common? I prefer to support the local shops, and I might go to NH to pay $450, but $750 just seems crazy! I'm wondering how different driving an hour is from ordering online (ie - it's not really local...).

 

[chimneylinerjames]

Prices do vary greatly. One reason is some places buy the liner from the manufacture and just have the liner delivered to your home. Other places you buy directly from the factory, eliminating the middle man and reducing your cost. Do your research, call the companies and ask what is different between company A and B. Check warranties and shipping cost also. They may vary.

 

[Rudyjr]

I have had good luck with ordering from Chimney Liner Depot. They have always had a good product, timely shipping, and a good price. My friends and I have all ordered from them and have all had good experiences.

 

[chimneylinerjames]

I have had good luck with ordering from Chimney Liner Depot. They have always had a good product, timely shipping, and a good price. My friends and I have all ordered from them and have all had good experiences.

Thank you for the good feedback. We always want to make sure that our customers are happy.

 

[Rudyjr]

Thank you for the good feedback. We always want to make sure that our customers are happy.

James, My only complaint is that everyone I have referred to CL Depot has gotten a free terra cotta top cap for their chimney when they mentioned that they were sent by me! Made me real jealous when I installed theirs for them. But otherwise you guys have been great to deal with! Keep up the good work, Jim

 

[webby3650]

Never got a call back on performance because of ovalizing

If the customer doesn't know the difference, they might not have a complaint.

Never got reports from sweeps indicating that there was excessive creosote build up

Excessive compared to what? Most sweeps see so many different set-ups that it's hard to compare one to another. There are so many out there that have excessive build-up, a sweep wouldn't stop what he's doing to call the installer to let him know of the issue. Besides their job is to sweep creosote.

nsulation below the top plate & in the damper area, EVEN on exterior chimneys

So why do you only insulate the area above the damper? Insulating the top makes good sense but at the bottom it's plenty hot. If your gonna do the top and the bottom, why not do the whole thing? It's super easy and doesn't add much to the cost. When I sweep a liner I can almost always tell exactly where the insulation starts and stops, by the amount of build-up.

 

[DAKSY]

If the customer doesn't know the difference, they might not have a complaint.


Excessive compared to what? Most sweeps see so many different set-ups that it's hard to compare one to another. There are so many out there that have excessive build-up, a sweep wouldn't stop what he's doing to call the installer to let him know of the issue. Besides their job is to sweep creosote.

No. The sweep wouldn't call the installer, but don't you think he might tell the homeowner? We've never gotten calls from either...


So why do you only insulate the area above the damper? Insulating the top makes good sense but at the bottom it's plenty hot. If your gonna do the top and the bottom, why not do the whole thing? It's super easy and doesn't add much to the cost.

Horse hockey. It adds time & time is money. Dead air between the insulated top & bottom IS INSULATION.

When I sweep a liner I can almost always tell exactly where the insulation starts and stops, by the amount of build-up.

Your feel is THAT good? Congratulations. We don't insulate all the way & we've been installing in the Northeast since 1979. It's quite obvious we don't know what we're doing. Oh, wait a minute. I forgot to mention that we insulate the bottom in the damper area with unfaced fiberglass & no blocker plate "GASP!!" Say it ain't so, Bob! We also use unfaced fiberglass under the top plate. "Oh No! You'll kill us with outgassing & melted glass!" We've never used Roxul or Kaowool or anything but unfaced fiberglass. I will stand by the owner of the company. He built a small home garage operation into 2 showrooms & a large warehouse. Four install crews & 3 service techs on the road every day...For anybody who just happens to be NFI Certified, he is respected enough in this industry that he wrote most of the questions on the certification test for wood burning appliances. I will not argue with you any more. You are all too smart for me. I only spent 11 years installing & servicing these appliances. Evidently I didn't make any mistakes, because no one died, & that's what happens when mistakes are made in this industry. If the other mods want to shut this down, fine. I'm just going to ignore further "Alerts"...

 

[webby3650]

Wow, nice!

 

[Rudyjr]

I am no installer or dealer but I have to agree that I have never seen any problems with unfaced glass insulation. That is all anybody had to use in our area in the 70's. The only time I have ever seen it melt was when a buddy took an oxy acetylene torch to some. If it gets that hot from a wood stove you got bigger problems than the off gassing. I used roxul in mine and my two friends installs because we have a commercial insulation contractor down the road that is kind enough to give us leftovers for free. I do think a blockoff plate makes the most difference in how my stove performs as far as heat output and I did insulate the area above it because I had insulation to do it and the top plate. I see absolutely no difference in the amount of creosote buildup in any area of my liner either insulated or not and I can see down it probably 8 feet, I clean my own chimney yearly.

 

[webbie]

This thread is a repetition of many in the past!

The problem with some of these answers is that "it depends". The standards have changed many times over the years - when I first started, a slip-in (no liner) was UL approved. For many years after that, a connection to the damper or toward the first flue time - uninsulated - was UL approved. This went on for a long time...even well into the EPA era!

There are almost too many possibilities to state any particular method as "fact". Some of it depends on the state of the existing chimney - other parts on the manual for the stove, others on the listing of the liner itself and many on what is found in the field.

As I understand it, in the worst case situations - that is, when a chimney is unlined and does not meet any sort of current standards - the liners need full insulation all the way up in order to bring the chimney up to HT standards. But there are exceptions even to this because some liner kits (Duraliner, etc.) are pre-insulated inside the metal, so useable as stock.

The way most of the instructions and listings put it, you need insulation to get up to 0 "zero) clearance specifications, meaning that the liner insulation could touch the unlined (or terracotta lined) walls of the chimney which then rest against wood framing.

I assume liner manufacturers have flexibility in the way they test - that is, they can specify that a liner has "x" air space around it or test it in a lined (terra-cotta) chimney and use those results for their instructions. But it makes sense that most would test for the worse case (unlined single brick thick resting against wood).....in which case, IMHO, they almost ALWAYS require a manufacturer approved or supplied full insulation.

Rather than reinvent the wheel, folks should search some of the site using the "search all of site" link on the forum top - and they will find threads such as this - which was started by a building official here in MA:
https://www.hearth.com/talk/threads...ated-chimney-liner-tell-us-about-yours”.2058/

In short- it's confusing, but some things are quite clear. Dangerous chimneys usually need insulation all the way up.

In the field, especially in cold climes, I would follow the rule to insulate when it is easily possible. However, there are many situations where it simply will not easily fit, etc. - these often require some kind of compromise, as the removal of flue tiles can be extremely difficult and even ruin the integrity of the chimney. Rectangular liners are made to help with such situations, however they rarely allow enough room for full insulation.

To address the point that "air is insulation", this is completely true - it even has a r-value, a fairly high one if I am not wrong. Therefore it would seem that if a R-value of insulation is called for, and it can be maintained through air and masonry, then it might pass code.

 

[Rudyjr]

Well said Craig.