Blazeking Ashford 30 install questions

[BKVP]

I haven't heard the term BBS is years. Reminds me of the pre-internet/dial-up modem days back in the 80s when individuals would host their own BBSs. I'm showing my age...

My first computer course in college involved punch cards. We thankfully upgraded to Fortran and then Cobol.

That's showing my age!

BKVP

 

[begreen]

No problem, I predate BBS... and modems.

 

[Drew777]

Actually double wall pipe added a significant amount to the quote. Initially I was quoted $2872 for the install, pipe included. I thought that was very cheap so I asked about the pipe and found out he quoted me for single-wall. He warned me that I'd be shocked by the quote for double wall. It added $1400 more to the price. I have 18ft ceilings / steep roof.

Assuming you'll need 18' of stove pipe someone's math is a little off. He shouldn't be charging you any more labor to install double wall.
Just generally, you can get 48" sections of Selkirk dvl at home Depot for $160, or Walmart online for $120. So let's just say $150 (I pay about $110 for these). 4 sections is 16' and another 24" gives you your 18'. A 24" section is like $70. That's $670 in pipe minus the $100 that won't be spent on the single wall pipe.
You'll need a telescoping pipe in there, that was just a general figure. So I have no clue how he's coming up w that price.

 

[Drew777]

Actually double wall pipe added a significant amount to the quote. Initially I was quoted $2872 for the install, pipe included. I thought that was very cheap so I asked about the pipe and found out he quoted me for single-wall. He warned me that I'd be shocked by the quote for double wall. It added $1400 more to the price. I have 18ft ceilings / steep roof.

Also your steep roof is going to require a decent amount of chimney pipe above your roof line depending on how far away from the ridge you are. You have to be 2' higher than any roof within 10'. If you're maybe another 7'+ out the roof you've got 25'+ of straight vertical run. I can't see you having any draft issues using single wall lol. But hey, we'll see if bkvp can chime in on that.

 

[stoveliker]

The point is not always draft issues. It's the cooling down of the gases, especially if the flue is tall. You want them to be above condensation at the cap to avoid build up in the pipe. The longer the travel the more it'll cool. So best to keep it warm and let the stove provide the heat as it is designed to do rather than the pipe.

 

[Drew777]

Thank you. When efficiencies began to rise and emissions began to drop, so did stack temperatures.

Stack temperatures play a role in how stoves perform. We do not suggest 100% of installs won't work on single wall pipe, but for every 10 calls we receive about poor draft performance, we know factually that stack length and single wall pipe are two likely culprits.

We now require photographs before we attempt any tech support. Just 2 weeks ago family were complaining the fuel load would not burn to completion. We emailed them a Tech Support Request form. With it were the pictures we require. 12' single wall.

We asked who installed the stove, "self". We were informed their prior stove never had any issues. They replaced the single wall with double wall, but kept it at 12'. "Runs great, whole new stove" was response....We said, wait until it gets cold and if you add 3' of class A, you'll be really happy.

Have you all noticed the most efficient stoves from various manufacturers are now recommending a specific vertical rise before transitions? The same manufacturers are recommending double wall stove pipe.

Respectfully, it's the combined knowledge and experience of an entire industry that prevail on this topic, not just me and my company.

BKVP

On an Ashford 30 - 18' of stove pipe to 7'+ of class A, straight vertical run. Is it feasible to run double wall stove pipe? I couldn't imagine someone having draft issues on any stove using single wall with a pipe run like that. What's your opinion?

 

[Drew777]

The point is not always draft issues. It's the cooling down of the gases, especially if the flue is tall. You want them to be above condensation at the cap to avoid build up in the pipe. The longer the travel the more it'll cool. So best to keep it warm and let the stove provide the heat as it is designed to do rather than the pipe.

I definitely hear you. But on any pipe run you're going to have the most heat at the bottom and the top. I can pretty much guarantee you that cap gonna be blazing hot on a pipe run like that lol. Would the whole system stay a little cleaner with double wall? Probably a little bit but nothing significant. Ultimately it does all fall back on draft issues, that's pretty much the focus of what BKVP was talking about.

 

[begreen]

I definitely hear you. But on any pipe run you're going to have the most heat at the bottom and the top. I can pretty much guarantee you that cap gonna be blazing hot on a pipe run like that lol. Would the whole system stay a little cleaner with double wall? Probably a little bit but nothing significant. Ultimately it does all fall back on draft issues, that's pretty much the focus of what BKVP was talking about.

History and a few past threads where measurements were taken say this is incorrect. The draft will be strong, but so will the heat loss over the 18' if single-wall stove pipe is used. Considering the flue gases are coming out of the stove at around 350-400º, a 100-150º temp drop in the stovepipe will mean a chimney that gets gunked up pretty quickly.

 

[BKVP]

On an Ashford 30 - 18' of stove pipe to 7'+ of class A, straight vertical run. Is it feasible to run double wall stove pipe? I couldn't imagine someone having draft issues on any stove using single wall with a pipe run like that. What's your opinion?

Feasible, yes. With existing installs with 6" single wall, we say go ahead and try. But be it known, you will likely need black double wall. For new installs, don't mess around and just go for the dbl wall.

BKVP

 

[Tron]

I haven't heard the term BBS is years. Reminds me of the pre-internet/dial-up modem days back in the 80s when individuals would host their own BBSs. I'm showing my age...

Same...

 

[Drew777]

Feasible, yes. With existing installs with 6" single wall, we say go ahead and try. But be it known, you will likely need black double wall. For new installs, don't mess around and just go for the dbl wall.

BKVP

Well if he has to pay labor to tear it out and replace it, that's not very feasible for the homeowner. If he was doing it himself I'd say take the chance being that the single wall pipe itself would only run about $100.

 

[Drew777]

History and a few past threads where measurements were taken say this is incorrect. The draft will be strong, but so will the heat loss over the 18' if single-wall stove pipe is used. Considering the flue gases are coming out of the stove at around 350-400º, a 100-150º temp drop in the stovepipe will mean a chimney that gets gunked up pretty quickly.

Which part was incorrect? Measurements of what? Was the single wall stove pipe the only factor? What point in the chimney would you expect it to get gunked up the most?

 

[BKVP]

Which part was incorrect? Measurements of what? Was the single wall stove pipe the only factor? What point in the chimney would you expect it to get gunked up the most?

Begreen is 100% spot on. Each of us has our own experiences. We have tens of thousands of those experiences in my 25+ years. Caps get plugged, spark arrestor screens get plugged and chimney class A get excessive accumulation in a large number of installations with the most efficient stoves mfgs make today.

I'm in Alaska this week visiting retailers. Across the state they recommend double wall on installs. This is because it gets so cold, it exacerbates the effect of cold stack on performance, creosote accumulation and required sweeping to keep system clear of excessive build-up.

BKVP

 

[stoveliker]

What point in the chimney would you expect it to get gunked up the most?

The part where the temperature first drops below the condensation point. From that point up you'll see build up.

Given that gases will inevitably cool during their way up, longer flues need higher initial gas temps and/or better insulation to limit cool down in order to stay above the condensation temp.
Higher initial gas temps is where efficient stoves have a problem because their efficiency means they shed the heat into the room rather than pumping it up the flue. So their exhaust is cooler than less efficient stoves.

For a BK that is in particular an issue when running low and slow (as little heat is being produced, and thus little is available to keep the flue warm enough).

Hence for taller flues, it's advisable to use double wall, especially for stoves that can turn down very low.

 

[Tron]

Which part was incorrect?

I'd say the part where you say that you're going to have the most heat at the bottom AND the top. The latter is incorrect.
The laws of physics (thermodynamics, to be specific) dictate that in a heat exchanger (which your flue effectively is) heat transfer is in a linear proportion to temperature difference. And energy transferred leaves less energy behind. So most heat will be shed at the bottom of the flue where temperatures are highest (and the temperature difference to room temperature is greatest), and both temperatures and heat transfer will drop the higher you go.

 

[Drew777]

Well guys this is all great info, particularly for the original poster to be able to make his decision which was my goal. Thank you.

 

[kevk]

Assuming you'll need 18' of stove pipe someone's math is a little off. He shouldn't be charging you any more labor to install double wall.
Just generally, you can get 48" sections of Selkirk dvl at home Depot for $160, or Walmart online for $120. So let's just say $150 (I pay about $110 for these). 4 sections is 16' and another 24" gives you your 18'. A 24" section is like $70. That's $670 in pipe minus the $100 that won't be spent on the single wall pipe.
You'll need a telescoping pipe in there, that was just a general figure. So I have no clue how he's coming up w that price.

I don't know either but I got three different quotes from local chimney shops in the area and they were all around the same price.

 

[Highbeam]

I don't know either but I got three different quotes from local chimney shops in the area and they were all around the same price.

I doubt the pro installers are quoting Selkirk plus as with auto parts at the mechanic you can expect an upcharge on parts for more profit.

 

[Drew777]

I don't know either but I got three different quotes from local chimney shops in the area and they were all around the same price.

I just realized you're in Georgia - you don't get crazy cold temps anything like Alaska as an example where these guys are talking about cold flue issues... Your location is definitely a factor to consider.

 

[Drew777]

I doubt the pro installers are quoting Selkirk plus as with auto parts at the mechanic you can expect an upcharge on parts for more profit.

What brands might they be installing?

 

[Tron]

I just realized you're in Georgia - you don't get crazy cold temps anything like Alaska as an example where these guys are talking about cold flue issues... Your location is definitely a factor to consider.

I'm two states over in MS, but similar climate. I have about 20' double-walled pipe, and no issues with creosote buildup whatsoever. I sweep roughly a cup or two out of the flue every year.

 

[kevk]

What brands might they be installing?

I spoke to my chimney guy, he said he only uses Metal Fab Temp/Guard. He said the pipe overlap on the Metal Fab is 1.5" vs less overlap on some of the others pipes out there (true statement or not I'm not sure). The chimney portion at the top is triple wall (2100 degrees F). The rest is Class A double walled black pipe.

I tried to price out Metal Fab Temp/Guard and the price point seems significantly higher than what I was seeing for DuraVent. I guess this makes a little more sense on the higher price for materials.

Interested in hearing thoughts on the quality or differences of Metal Fab / Temp Guard.

 

[kborndale]

If I'm remembering correctly the triple walled chimney pipe is not very good, doubled walled is much better quality.

 

[stoveliker]

If that is what he said, he does not know what he is saying.
Chimney should be class A.
Black pipe is not.

You want double wall black pipe and class A chimney (which is insulated double wall, not the worse triple wall).

 

[kevk]

If that is what he said, he does not know what he is saying.
Chimney should be class A.
Black pipe is not.

You want double wall black pipe and class A chimney (which is insulated double wall, not the worse triple wall).

Sorry I added the "class A" part in there, I had just read that double walled is called Class A so I assumed that is what the black pipe was called too. Apologies.

So double walled black pipe up to the chimney. Then a 2100 degree chimney - I thought he said the part going through the roof is triple walled.