Chimney Liner recommendations needed please!!!

[deercamp]

I will finally be purchasing the Harman 52i Accentra insert after many hours of research on here.
Now that all my research on the stove itself is done it's time to figure out what 20' chimney liner
to get. I will be installing everything myself. I have been reading some reviews on the liners already
and just like the stove I over analyze until my head is about to explode. Some of the liners that I have been looking at are Flex King, Duravent, Rock Flex, Metal-Fab, Fire Flex. Have I missed any (LOL) ?
I am paying big money for the stove and I am not going to cheap out on a liner. Any input on what
liner I should get would be greatly appreciated. Ty

 

[NHcpa]

I will finally be purchasing the Harman 52i Accentra insert after many hours of research on here.
Now that all my research on the stove itself is done it's time to figure out what 20' chimney liner
to get. I will be installing everything myself. I have been reading some reviews on the liners already
and just like the stove I over analyze until my head is about to explode. Some of the liners that I have been looking at are Flex King, Duravent, Rock Flex, Metal-Fab, Fire Flex. Have I missed any (LOL) ?
I am paying big money for the stove and I am not going to cheap out on a liner. Any input on what
liner I should get would be greatly appreciated. Ty

ICC Excel. Having Accentra insert installed and the stove dealer quoted me this pipe. FYI, he is installing the damper block off and sealing the exhaust pipe at the crown/exit. the pipe itself will not be insulated - internal located 2 story clay lined chimney.

 

[john193]

This is where I got mine.

(broken link removed)

US made SS liner.

 

[batchman]

I'll +1 the ICC Excel for the vent if you need double walled pipe. Seems well made and goes together well with the exception of my 90deg elbow mating to a flex adapter (which I have at a masonry adapter) - if you have that combo get the seller to put that one together for you!

Good luck,
- Jeff

 

[CBL]

I bought throigh chimney liner depot and went with one of their flex king pro double wall liner kits, it also came with a sealing plate and cap, insanely fast order processing and shipping... Really couldnt complain about their service and it's a really nice quality liner.

 

[deercamp]

I forgot to mention that I need a flex liner. When I went to ICC Excel's website I didn't notice any
flex liner's. What are the pro's and cons for a double wall versus a single wall liner for pellet venting?

 

[john193]

I forgot to mention that I need a flex liner. When I went to ICC Excel's website I didn't notice any
flex liner's. What are the pro's and cons for a double wall versus a single wall liner for pellet venting?

Are you going through a masonry chimney? If so it is very likely you can go with single wall. Check your local code.

 

[tjnamtiw]

I used single wall flex in both of my chimneys. One is 17' and the other is about 20'. One is inside the house and one outside. No problems with either one after 4 years.

 

[mik_kane]

I was shopping around for flex chimney liners and these are the 2 best prices I found. Not sure on the quality maybe someone can comment on that.

Flex King PRO Chimney Liner - 4X20 - Insert Kit
http://www.chimneylinerdepot.com/store/3852/product/Flex-King-PRO-Chimney-Liner-4X20-Insert-Kit.html

Flex King PRO Chimney Liner - 4X20 - 316ti - Insert Kit
(broken link removed)

Quick question is there any big difference on smooth wall liners and just regular liners for a pellet stove?

 

[tjnamtiw]

Don't know about smooth vs regular. Mine was 3" regular and works great. My liner starts out vertical so my EVL is very small. If you're is vertical, I really question why you would need 4" for 20 foot vertical. It's not necessary and it's easier to get around the smoke shelf and there's less surface area to cool the exhaust plus your exhaust will move faster.

 

[mik_kane]

I'm pretty sure my EVL will come out to 17-19. 2-90's, 1-2ft horizontal, and about 12ft vertical

1. Each 45 degree elbow = 3 EVL
2. Each 90 degree elbow and Tees with cleanout = 5 EVL
3. Each foot of horizontal run = 1 EVL
4. Each foot of Vertical run = 0.5 EVL

 

[tjnamtiw]

You're going to have 2 90's on an insert??? Where? Does Harman have a vertical outlet option? Shame on them if they don't!

If you use a cleanout = 5 plus 12 feet of vertical = 6 that's only 11 EVL.

 

[CBL]

I was shopping around for flex chimney liners and these are the 2 best prices I found. Not sure on the quality maybe someone can comment on that.

Flex King PRO Chimney Liner - 4X20 - Insert Kit
http://www.chimneylinerdepot.com/store/3852/product/Flex-King-PRO-Chimney-Liner-4X20-Insert-Kit.html

Flex King PRO Chimney Liner - 4X20 - 316ti - Insert Kit
(broken link removed)

Quick question is there any big difference on smooth wall liners and just regular liners for a pellet stove?

That's the liner I used and bought it from the same vendor. Really good quality and fast service.

I did get the smooth wall liner as they claim it can improve draft performance. My thought was because the ID of the liner is smooth you'll get less build up of ash when compared to a single wall liner where ash could get hung up between each pleat, plus the double wall uses slightly better stainless steel.

 

[deercamp]

I am pretty sure that the 52i insert has a
4" exhaust. The pipe attaches to the back of the cage. So I thought that when I came through the block off damper plate it would attach directly to the cage without using a 90. I thought the bigger the pipe the better draft is that correct?

 

[tjnamtiw]

I am pretty sure that the 52i insert has a
4" exhaust. The pipe attaches to the back of the cage. So I thought that when I came through the block off damper plate it would attach directly to the cage without using a 90. I thought the bigger the pipe the better draft is that correct?

http://www.woodheat.org/how-chimneys-work.html > ''people used to think that bigger is better. Now it is clear that bigger is not better when it comes to chimney sizing. A given volume of flue gas flows faster and has less time to lose heat in a small chimney flue than in a large one.''

I see from the manual that your stove DOES have a 4" VERTICAL outlet so you don't need or want any of those 90's and you'd do well to stick with 4" flex pipe. Your only component of EVL is the vertical height of your chimney. Remember that these stoves use positive pressure to BLOW the exhaust out the chimney and don't rely on draft as much as a wood or coal stove although if the power goes out, you want some vertical height to generate some draft to keep smoke from filling your room. Also, flue gases from the stove are MUCH cooler at around 160 to 180 degrees, I believe. Much higher and you are wasting heat. Mine are at 160.

 

[deercamp]

I think that my liner is more like
15' and not 20'. I don't know how much of a difference the height makes on
the draft. The flu is clay lined so I am sure that a single wall would be fine but
was just thinking that a double wall might be a little safer.

 

[deercamp]

How do you calculate your EVL?
What exactly is EVL? Ty

 

[mik_kane]

How do you calculate your EVL?
What exactly is EVL? Ty

http://nevelsstoves.com/pellet-stove-venting.html

Pellet stoves have to push the exhaust air through the vent pipe with the stove's exhaust fan. With less restriction your pellet stove will breathe easier and burn more efficiently. First let's clarify the word restriction. Restrictions come from several different items.

1. 45 degree elbows
2. 90 degree elbows
3. Horizontal distance
4. Vertical distance
5. Elevation where you live.

A rule of thumb equation we are using has been adopted by most pellet manufactures. The equation is called the sum of Equivalent Vertical Length (EVL). All of the above mentioned venting restrictions have been assigned EVL values as follows:

1. Each 45 degree elbow = 3 EVL
2. Each 90 degree elbow and Tees with cleanout = 5 EVL
3. Each foot of horizontal run = 1 EVL
4. Each foot of Vertical run = 0.5 EVL
5. Elevations above 3000 ft with an EVL of 7 must adapt to 4 inch vent pipe.

If your installation is below 3000ft, we would need to do some math. The rule of thumb equations is that if the sum of the EVL is 15 or greater, then the pellet vent pipe would be increased to 4 inch diameter pellet vent pipe.

 

[tjnamtiw]

When reading your manual, I noticed that they don't directly talk about EVL. Instead, they just say that certain pieces of pipe reduced the allowable overall length. From a Quad manual, you can see how different pipes have different influences in 'overall length'. Vertical pipe presents itself as 1/2 of the actual length.



Double wall pipe wouldn't really have any bearing IMHO on safety since it's inside of a safe masonry chimney. It could only serve the purpose of keeping the flue gases hotter because of the insulation. Less condensation and buildup of creasote - PERHAPS. Actually I wasn't aware that they even made double wall flexible liners. I've heard of insulated liners but not double wall. http://www.firesidechimneysupply.com/chimney-liner-insulation.html

EVL= Equivalent Vertical Length.

 

[CBL]

I think that my liner is more like
15' and not 20'. I don't know how much of a difference the height makes on
the draft. The flu is clay lined so I am sure that a single wall would be fine but
was just thinking that a double wall might be a little safer.

Personal choice at the end of the day. Either one will work just fine. With the benefits of the 2-ply liner one drawback is they are not as flexible as a single wall is and need a bit more English when snaking into the flue and past the damper.

 

[deercamp]

http://nevelsstoves.com/pellet-stove-venting.html

Pellet stoves have to push the exhaust air through the vent pipe with the stove's exhaust fan. With less restriction your pellet stove will breathe easier and burn more efficiently. First let's clarify the word restriction. Restrictions come from several different items.

1. 45 degree elbows
2. 90 degree elbows
3. Horizontal distance
4. Vertical distance
5. Elevation where you live.

A rule of thumb equation we are using has been adopted by most pellet manufactures. The equation is called the sum of Equivalent Vertical Length (EVL). All of the above mentioned venting restrictions have been assigned EVL values as follows:

1. Each 45 degree elbow = 3 EVL
2. Each 90 degree elbow and Tees with cleanout = 5 EVL
3. Each foot of horizontal run = 1 EVL
4. Each foot of Vertical run = 0.5 EVL
5. Elevations above 3000 ft with an EVL of 7 must adapt to 4 inch vent pipe.

If your installation is below 3000ft, we would need to do some math. The rule of thumb equations is that if the sum of the EVL is 15 or greater, then the pellet vent pipe would be increased to 4 inch diameter pellet vent pipe.

I think we'll have to get out the calculator. The elevation in my town is 212'. So if my liner is only 15' and
I have a straight shot up the chimney with only maybe a 45 or 90 needed to connect the liner to the cage
that would be an EVL of a lot smaller than 15. Does this mean that a 3" exhaust pipe would be a better
option for my install then a 4" exhaust?

 

[tjnamtiw]

You're going to run your liner straight up from the outlet of the blower which, in the diagram I saw in the manual, is facing straight up. You'll probably put what's called an appliance adapter on there and then right to the flex liner. I'll let more knowledgeable people explain that one. The only thing you have will be is your chimney height. If it's 16', then your EVL is 8'.
Since your outlet is 4" and your manual says to use 4", I would use 4". My manual said 3" unless my EVL was above a certain amount, which I can't remember. My EVL was 8.5'.

 

[deercamp]

I checked the manual and it does mention 3" liner's for smaller chimney's. So having a straight shot up from the back of the stove and not needing any 90's I think that I should go with a 3" liner. What will I need to attach to the 4" exhaust
on the back of the stove to reduce it down to 3"? Do you think I am doing the right thing by going with the 3"liner?

 

[alternativeheat]

I checked the manual and it does mention 3" liner's for smaller chimney's. So having a straight shot up from the back of the stove and not needing any 90's I think that I should go with a 3" liner. What will I need to attach to the 4" exhaust
on the back of the stove to reduce it down to 3"? Do you think I am doing the right thing by going with the 3"liner?

No, I would go with 4" right to the top. I would never reduce down. Besides that, when I was considering the 52i the dealers installer said to go with 4" even if straight out the back on the 52i.. As it turned out I went with the P61 and 4" flex anyway ( 20+ ft in a masonry chimney, one T at the bottom). I have not built a bit of creosote even with some low burning time put in and have excellent draft for power outages. I have never pulled that bottom cap and seen condensation in there even on the coldest day. I will say I had a bit of stuffing to do getting past the smoke shelf but doable.

 

[tjnamtiw]

I'd have to agree with alternativeheat since you have 4" coming out of the stove. Hopefully, it will clear the smoke shelf with the damper removed. 3" is easier and my stove has no problems with pushing the air up 17' but you have to ask yourself why they have 4". I didn't notice the reference to 3" though. How's that for non-committal? I think you would be fine either way but it's up to you. They do offer reducers, if you go that route.