Double Wall?

[Troutchaser]

The clearance on my interior pipe is for double wall. That baby is getting hot. Yes, it is straight up from the stove, which is going to help it pick up heat. But I've registered temps of 400 on that pipe.
How can I tell if this is double wall by measuring or looking?
I'm actually planning to install a probe thermometer tomorrow after cool down, but this is driving me crazy tonight. That pipe is only 6 and 1/4 inches diameter as best I can tell.
Can this be a double walled pipe?

 

[Highbeam]

Look at where it goes into the stove. The single wall pipe will go inside the stove's collar and double wall will shroud the collar. The 6" double wall pipe outer diameter is 7" and has a sticker on the back.

You could always remove it and look inside too.

Outer shell temps of 400 are expected on single wall during a pretty hot fire. To get the outer shell of double wall to 400 you would almost have to have a chimney fire going. I can touch the outer wall of my double wall when the flue temp is at 1000 which is the max continuous temp allowed for the pipe.


Sounds like you have single wall.

 

[fossil]

^ Totally agree...sounds like single wall pipe. Prob'ly needs to be replaced. Good heads up on your part for paying attention & recognizing a problem before it turned into a disaster. Who did the installation, and when? Rick

 

[WES999]

FYI, I just measured the temp on my stove pipe( Simpson double wall).
Flue temp inside 470 °F , outside surface temp 140 °F .
Both measured with thermocouple and electronic temp meter.
Sounds like single wall.

 

[Troutchaser]

Thanks gang.
I installed the probe therm. this morning and found that I do indeed have double wall. Also, yes, I can tell now by the connection into the stove. I'm at 700 inside flu temp right now and 275 on outside of DW. Stove is about 550. Definitely not something I can hold my hand on.
Is something wrong with that?

BTW- I can see already that I've run some pretty serious pipe temps before now. Doesn't take much to hit that 1000 mark really. I know I've gone past that in the last two weeks.

If stove is 500 and internal pipe is 450 does that take me out of the creosote range? Or are there a lot of other factors?

 

[DanCorcoran]

There should be info in your Lopi manual (or in the online version) which specifies optimum stove surface and flue temperatures for your particular stove.

 

[Troutchaser]

Thanks Dan, but I don't think it's there. Manual says overfiring is 800deg. Nothing else about stove top or flue temp.
I'm with other Leyden owners in this forum that placement of stove therm. is confusing. Temps. vary widely and the manual does say to place it over the door (not top loading lid mind you).
Looks like a trial and error deal. Right now I'm just trying to stay within the parameters recommended on the thermometers. Over 400 on both stove and flue.

 

[Highbeam]

Lopi won't tell you how hot to run your flue, only overfire temp for your stove and you're lucky to get that. If your probe meter is like mine it shows 400 as the minimum flue temp to prevent creosote. I tend to agree and have also found that if you are under 400 that the fire is a smoldery mess making smoke outside anyway. Who cares if your stove has creosote in it? You don't hear of many folks with unintentional stove fires. That said, we keep or stove in the 300-550 range all the time with most time spent at 350-400. Temps move slowly in a stone stove.