Short 5.5" liner on a 6" insert?

[Mr4btTahoe]

Hey guys...

Helping my brother with an install and he currently has an old clay lined fireplace. We are getting ready to install a Buck insert that has a 14x3.5" rectangle output. It was originally installed just vented open up the old chimney... no adapter... no liner... just the insert slid into the fireplace opening (this was how it was installed at the house that he bought it from).

We are planning on getting a stove boot and running a stainless liner in this install... however the inside dimensions of his current clay liner is only 5-7/8" so a 6" liner is out.

Will a 5.5" liner be ok? The chimney is on an exterior wall and will only be 15' from stove top to rain cap.

Thanks for any input.

 

[bholler]

Hey guys...

Helping my brother with an install and he currently has an old clay lined fireplace. We are getting ready to install a Buck insert that has a 14x3.5" rectangle output. It was originally installed just vented open up the old chimney... no adapter... no liner... just the insert slid into the fireplace opening (this was how it was installed at the house that he bought it from).

We are planning on getting a stove boot and running a stainless liner in this install... however the inside dimensions of his current clay liner is only 5-7/8" so a 6" liner is out.

Will a 5.5" liner be ok? The chimney is on an exterior wall and will only be 15' from stove top to rain cap.

Thanks for any input.

That stove needs an 8" liner or a rectangle equivilant of it. It wont work on a 6" much less a 5.5

 

[Mr4btTahoe]

Thats no good. He didn't have the model information when he bought the unit used. I just now got the model number off of it and looked it up. This ain't gonna be usable for him. Back to the drawing board.

 

[Mr4btTahoe]

Doing some reading... some have gotten away with running similar sized stoves on 6" liners. Is there a legitimate safety concern with trying such or will it just be a performance issue?

From what I've read, most of the time, the 8" was a requirement due to the option of keeping the doors open and using a screen making them more like a fireplace. Those that don't use that... just operate it as a typical stove claim that they draft fine and don't have issues...

The question is, more then likely, we'll have to go with a liner no matter what. Cant fit an 8" liner and most inserts are 6" now days anyways...

I'm tempted to go on and install a 6" liner and try this stove.. see how it operates on it (as long as it isn't a SAFETY issue... but just a performance issue). If it wont operate/draft well... pull it out and sell it.. find a 6" insert instead.

Does this sound feasible? Even with busting out the clay liner, there isn't room for an 8" liner.

 

[begreen]

That's a narrow flue. What is the other dimension of the current clay liner? 5 7/8" by what?

 

[Mr4btTahoe]

That's a narrow flue. What is the other dimension of the current clay liner? 5 7/8" by what?

7x9 are the outside dimensions of the clay liner. It has 2 clay liners inside the brick chimney.. one runs to the basement for what we assume was an old coal stove and one runs to this fireplace. Not 100% certain on inside dimensions but 5-7/8 was the short direction... so I'd guess 7-7/8 for the long direction. It is clean and vertical.

My brother is a state away.. he's gathering parts before I head down there to help him get finished.

Even if he cuts out the clay liner on that side, an 8" oval liner still wont clear.

I'm leaning towards him getting a true 6" liner that we can slightly oval and work into place. He will only use the insert as a stove.. wont use the screen. Hook it up and see what it does. If it doesn't perform well, then pull it out.. sell it and find another insert with a 6" collar. At this point, he's already got that 600# monster sitting in front of where it needs to go.. might as well try it.

 

[begreen]

That flue sounds quite undersized for a fireplace. It's only about 48 sq in cross sectional area, close to 8" round. I was thinking of an ovalized liner. What transition piece is he going to use to go from the long rectangular flue outlet to oval or round? Is there enough headroom to to fit?

 

[Mr4btTahoe]

The stove didnt come with the rectangular to round adapter which is the main reason he didn't know it needed an 8" pipe. They just had it slid into their fireplace and had the flue outlet open... no liner.. no adapters.. nothing.

He's got a decent amount of head room... and he's got the tooling to make the adapter from scratch or buy one of the originals if we can find one.. then adapt it down.

At this point, he doesn't want to spend the money to do an 8" install considering most modern inserts are 6" and he'd be back to square 1 if he ever changes the stove. I'm thinking 6" now and change the stove now if it doesn't draft well enough.

 

[bholler]

The stove didnt come with the rectangular to round adapter which is the main reason he didn't know it needed an 8" pipe. They just had it slid into their fireplace and had the flue outlet open... no liner.. no adapters.. nothing.

He's got a decent amount of head room... and he's got the tooling to make the adapter from scratch or buy one of the originals if we can find one.. then adapt it down.

At this point, he doesn't want to spend the money to do an 8" install considering most modern inserts are 6" and he'd be back to square 1 if he ever changes the stove. I'm thinking 6" now and change the stove now if it doesn't draft well enough.

You might get away with it if you have 25+ feet but with a short chimney it will smoke like crazy and make tons of creosote. More than those stoves usually make

 

[begreen]

What about removing the damper and attaching a plate with an 8" round collar to the bottom of the current chimney tile, then direct connecting it with flex to the stove transition?

 

[bholler]

What about removing the damper and attaching a plate with an 8" round collar to the bottom of the current chimney tile, then direct connecting it with flex to the stove transition?

If the chimney is to code that could work.

 

[Mr4btTahoe]

What about removing the damper and attaching a plate with an 8" round collar to the bottom of the current chimney tile, then direct connecting it with flex to the stove transition?

The current liner looks to be in decent shape... but who knows. The house is old and this fireplace was covered over YEARS ago and the chimney had been stuffed with insulation. I gave him the option and he is going to see if he can find a local sweep that'll come take a look at it. If it's in good shape, it would certainly be cheaper/easier.

I'll let you know what he figures out. Hopefully he can get someone out there next week.

 

[Mr4btTahoe]

Update... been on vacation all last week.

My brother had a sweep come out and take a look at things. Guy said it looked as if the flue had never been used.. was spotless. No cracking.. no signs of any issues... and he was running late which made my brother late for work so the guy didn't charge him. Lol

Anyways... so now the plan is to flat plate the bottom of the tile and run a short section of 8" from the stove to the clay liner. He's working on making the plates and such this week so hopefully he'll be up and running next weekend.

 

[Rickb]

I believe this method is called direct connect. I would think this would be a PITA to clean and the draft would not be very good.

 

[bholler]

Update... been on vacation all last week.

My brother had a sweep come out and take a look at things. Guy said it looked as if the flue had never been used.. was spotless. No cracking.. no signs of any issues... and he was running late which made my brother late for work so the guy didn't charge him. Lol

Anyways... so now the plan is to flat plate the bottom of the tile and run a short section of 8" from the stove to the clay liner. He's working on making the plates and such this week so hopefully he'll be up and running next weekend.

Did the sweep check for proper clearances from the outside of the chimney to combustibles?

 

[Mr4btTahoe]

Did the sweep check for proper clearances from the outside of the chimney to combustibles?

Not sure as I wasn't there. He told my brother that it was good to go. I mean.. its an exterior brick chimney with 2 clay liners.. no combustibles all that close to the liners but I would have thought that a professional would know what to look for.

Again.. not sure though as I wasn't there.

 

[begreen]

Similar story and question here:
https://www.hearth.com/talk/threads/sierra-classic-2000-hearthstove-flue-connection.170639/

 

[bholler]

Not sure as I wasn't there. He told my brother that it was good to go. I mean.. its an exterior brick chimney with 2 clay liners.. no combustibles all that close to the liners but I would have thought that a professional would know what to look for.

Again.. not sure though as I wasn't there.

He needs to have 1" clearance to combustibles from the outside of that brick it can have trim touching the corners but not the face.

And yes you would think a pro would know what to look for. Unfortunately many dont bother.