help please hearth pad and new stove thimble questions

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begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Yes, a hole is drilled through the two layers of the pipe with the inner pipe hole smaller than the outer wall hole. A surface magetic thermometer will not provide a meaningful reading on double-wall stove pipe.
 

Shrewboy

New Member
Oct 15, 2020
71
Eastern Pennsylvania
i’ve seen some magnet ones, will that work?

what temp should the front be closed off by?

having a wood stove growing up, we just stuck wood in. the flue was a flappy disc that you could turn, so we would turn it so that it stood up and down letting all the air through when we first lit it. Then a couple hours later when we came to add more, we would close it maybe 1/2. i don’t think we had anything more complex than that.

these days seems i’ve got to know about wood moisture, wood type, air direction, loading direction, radiant heat output/directionality, touch temp, and now flue temp.. i don’t know anything about flue temp. What is normal?

I know there’s a such thing as over burn and that’s when you’re fire is too hot, red glow hot. What would you do if that happened? I know shut off the air. I suppose if i has a metal bucket i could also remove wood/embers..

this is all more than i remember. so much is new.
Thank you for all your help and patience
A good option is putting an adjustable damper into the stove pipe, so you can cut more of the air off, in case the stove starts to get too hot and it isn't slowing down with air intake set to minimum.

 
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rosieXdox

New Member
Sep 29, 2021
43
new jersey
the endeavor has a bypass damper thing in the rear of the stove which if closed forces air into a smaller pathway. but i think you’re right if i wanted to really choke it i could get one of these.
that’s a good suggestion
 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
Begreen is there a place that says what temps should be followed for stove top and stove pipe temps?

I’ve tried looking into the thermal difference from internal pipe to external pipe and haven’t really seen anything concrete. but i would think it’s got to be somewhere..
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,670
central pa
Begreen is there a place that says what temps should be followed for stove top and stove pipe temps?

I’ve tried looking into the thermal difference from internal pipe to external pipe and haven’t really seen anything concrete. but i would think it’s got to be somewhere..
There is no set answer for internal vs external for double wall pipe. You need a probe thermometer
 
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begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Begreen is there a place that says what temps should be followed for stove top and stove pipe temps?
Double-wall stove pipe needs a probe thermometer.
the endeavor has a bypass damper thing in the rear of the stove which if closed forces air into a smaller pathway. but i think you’re right if i wanted to really choke it i could get one of these.
that’s a good suggestion
The bypass doesn't restrict the pathway. It reroutes the flow of smoke in the firebox from going straight up the flue to around the baffle and secondary tubes. This is much more efficient. It is only meant to be used to start the stove or temporarily route the stove right up the flue when reloading. A probe thermometer will show how much heat is being wasted up the flue with the bypass open.
 
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rosieXdox

New Member
Sep 29, 2021
43
new jersey
Ok. What pipe temps am i looking to maintain?
What stove top temp should i maintain?
This is a lot more complex than I was a kid where you just watched the fire for the right look and if it was cold you added more wood..
 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
Thank you Begreen.
I wondered if it restricted enough to also help slow a runaway fire/over heat? that’s what i was asking. thinking it would be somewhat restrictive.
i do know they want it open only when starting for about 45 mins to an hour, and then only just prior to opening the glass door when going to load it to keep smoke from puffing in your face and into your home.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Ok. What pipe temps am i looking to maintain?
What stove top temp should i maintain?
This is a lot more complex than I was a kid where you just watched the fire for the right look and if it was cold you added more wood..
Eventually, you will learn by watching. Stovetop temps are less meaningful than flue temps because a cold stove takes time to warm up all the metal, even though the firebox is hot. Normal stove top temps will be around 400-650º with flue temps about the same once the air has been turned down. Did you read this thread?
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Thank you Begreen.
I wondered if it restricted enough to also help slow a runaway fire/over heat? that’s what i was asking. thinking it would be somewhat restrictive.
i do know they want it open only when starting for about 45 mins to an hour, and then only just prior to opening the glass door when going to load it to keep smoke from puffing in your face and into your home.
No, it does not. With good draft and dry wood the bypass should be only open for 5-10 minutes, not 45 minutes. In cold weather maybe only a minute or two. Our stove has no bypass and once outdoor temps are below 50º there isn't any smoke spillage. Above that temp the spillage is minimal as long as one opens the door slowly.
 
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rosieXdox

New Member
Sep 29, 2021
43
new jersey
Begreen I got the 45 minutes from the wood stove people. The Lopi youtube videos say 15 minutes. i think the instruction manual also said 15/20 minutes.
the longer time was apparently to ensure the pipe was hot enough for 2 things- 1 prevent or burn off creosote from overnight coals burn, 2 good or better draft?
 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
I think i have read it Begreen, but honestly i’m a little information overload here and i’m just drowning in numbers and confusion. today i sent my well healthy kid in to school only for him to be told he has to go home since it hasn’t been 10 days yet since he had a cough after a runny nose. and I didn’t know that was a rule.
i am just totally lost with so many things right now.

i really do appreciate all your help and a bit of hand holding through this. it’s completely and totally different than what i’m used to.

i’m am over thinker already and offend worry if i’m worrying too much or making things more complicated just worrying about all the ways i’m not doing exactly the right thing
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,670
central pa
Bholler, they’ve got to know the thermal reduction value in order to reduce the clearance to combustibles... right?
They know what the highest possible outside temperature is with a chimney fire in the double wall pipe is. That is what they base clearances upon. There is no set ratio between inside temp and outside of double wall.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
Begreen I got the 45 minutes from the wood stove people. The Lopi youtube videos say 15 minutes. i think the instruction manual also said 15/20 minutes.
the longer time was apparently to ensure the pipe was hot enough for 2 things- 1 prevent or burn off creosote from overnight coals burn, 2 good or better draft?
These are general guidelines, each installation is different. The amount of time will vary with the strength of the draft and the dryness of the wood. As the outdoor temperatures get colder the draft strength will increase. In mild weather you may find yourself leaving the bypass open for ten or fifteen minutes and in the dead of winter, maybe only 5 minutes. The length of time will vary with the how the fire is built, the amount of kindling used and draft strength.

It seems like a lot to process at first, but after a few successful fires it will become second nature. A flue thermometer will be helpful in building confidence. Sorry about the sick kiddo, schools are being understandably cautious right now.
 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
agree about being cautious.

i would always bear to the side of caution.

do i understand correctly that the double wall pipe is rated at chimney fire temps to calculate its clearance to combustibles- as in the outer pipe doesn’t reach whatever the set temp is for allowing it to touch combustibles? as in - even when it’s actually on fire it’s still safe to the combustibles surrounding or touching at certain points?

I’ve lit and burned a lot of fires. I still burn fires outside.
in fact i have been lighting smokey fires outside to smoke out the dang mosquitos. I can make a really smoky fire. for hours with all this wet wood we have just lying around from the previous owner.

anyway, it’s all or mostly hardwood like oak.

I used to start a fire base up method. Idk the “tunnel of love” method mentioned and some of the other terms were lost on me. (what’s a neophyte?)

for us it was simple, whatever wood we had, we would shove it in. I guess they’d be called splits. but definitely like 1 log with bark on would be 4 pieces, talking a dinner plate diameter log. no idea what kind of wood or if it was any percent dry. we got it from a family, we had become neighborly friends with, every year. sometimes itd boil out the ends. the wood stove glass was always black, brown or that yellow color. you could tell there was a fire by the firelight flickering through but couldn’t see clear flames if you tried.
we would go by how does the flame look, how does the house feel?
so let’s say the fire was out. cold start. morning. december. it was crumpled up newspaper or junk mail, and those big pieces right on top. i don’t think we knew what kindling was...... anyway, it took a long time to light those fires. lots of fiddling and trying more newspaper, maybe cardboard. we found you can light a piece of spaghetti and the end stays lit longer so you can light it over and over or in many spots.
it would probably 15 minutes of that and then finally a flame would catch well.
then it was leaving the door ajar probably at least an inch.
the flue would be open this entire time btw.
after there was steady flames the door was shut. and the flue was adjusted. sometime the flue took some fiddling where you’d close it and bam the fire would just keel over. or you’d open it too much and you’d be reloading again.
fiddling. a lot of fiddling.

we had no way of knowing the stove top temp or the stove pipe temp. it got hot. we knew that much.

the people who built this house originally did have a stove pipe thermometer and they would keep it in a safe range. though they didn’t remember the number.
i don’t know if they had single or double wall pipe, but i know they watched it because they knew about the clearance to combustibles issue they had somehow passed despite. (they passed inspection)

the new stove is going to come last october early november. sometime.
i have never used a stove like this, reburn tubes and all. that’s why i’m trying to read up and fill my brain.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
25,670
central pa
agree about being cautious.

i would always bear to the side of caution.

do i understand correctly that the double wall pipe is rated at chimney fire temps to calculate its clearance to combustibles- as in the outer pipe doesn’t reach whatever the set temp is for allowing it to touch combustibles? as in - even when it’s actually on fire it’s still safe to the combustibles surrounding or touching at certain points?

I’ve lit and burned a lot of fires. I still burn fires outside.
in fact i have been lighting smokey fires outside to smoke out the dang mosquitos. I can make a really smoky fire. for hours with all this wet wood we have just lying around from the previous owner.

anyway, it’s all or mostly hardwood like oak.

I used to start a fire base up method. Idk the “tunnel of love” method mentioned and some of the other terms were lost on me. (what’s a neophyte?)

for us it was simple, whatever wood we had, we would shove it in. I guess they’d be called splits. but definitely like 1 log with bark on would be 4 pieces, talking a dinner plate diameter log. no idea what kind of wood or if it was any percent dry. we got it from a family, we had become neighborly friends with, every year. sometimes itd boil out the ends. the wood stove glass was always black, brown or that yellow color. you could tell there was a fire by the firelight flickering through but couldn’t see clear flames if you tried.
we would go by how does the flame look, how does the house feel?
so let’s say the fire was out. cold start. morning. december. it was crumpled up newspaper or junk mail, and those big pieces right on top. i don’t think we knew what kindling was...... anyway, it took a long time to light those fires. lots of fiddling and trying more newspaper, maybe cardboard. we found you can light a piece of spaghetti and the end stays lit longer so you can light it over and over or in many spots.
it would probably 15 minutes of that and then finally a flame would catch well.
then it was leaving the door ajar probably at least an inch.
the flue would be open this entire time btw.
after there was steady flames the door was shut. and the flue was adjusted. sometime the flue took some fiddling where you’d close it and bam the fire would just keel over. or you’d open it too much and you’d be reloading again.
fiddling. a lot of fiddling.

we had no way of knowing the stove top temp or the stove pipe temp. it got hot. we knew that much.


the people who built this house originally did have a stove pipe thermometer and they would keep it in a safe range. though they didn’t remember the number.
i don’t know if they had single or double wall pipe, but i know they watched it because they knew about the clearance to combustibles issue they had somehow passed despite. (they passed inspection)


the new stove is going to come last october early november. sometime.
i have never used a stove like this, reburn tubes and all. that’s why i’m trying to read up and fill my brain.
What you are describing sounds like symptoms of wet wood. You will most likely have the same issues with the new stove if you are using the same type of fuel.

And yes double wall pipe is tested at the highest possible temp to determine what safe clearance to combustibles is. And no combustible material can ever touch it. It always needs to be atleast 6" for some pipe it is 9" above
 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
for this new stove I won’t be following any of the example of my family (growing up).
This new stove will be in my first home. Which is really important to me that I step away from the wrongs and carelessness of my family growing up, and make my own path. I want to do things right.

The wood we are getting is from my in-laws wooded land. They have a lot of hardwood they harvest there. We also have a lot of downed trees on our new property. many piles of round logs just have been sitting in piles. The bark is wet, dirt sodden and much is soft or rotten at least an inch or so deep. This is the wood I have been using in my outdoor fire pit to combat the mosquitos. Using up cardboard to help smoke them out.

I’m glad that I’ve found in some posts the reccomendafion for over night burns to either pack the wood stove on top embers just prior to bedtime, or to fill it with rounds. Is this accurate?
 
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bholler

Chimney sweep
Staff member
Jan 14, 2014
25,670
central pa
for this new stove I won’t be following any of the example of my family (growing up).
This new stove will be in my first home. Which is really important to me that I step away from the wrongs and carelessness of my family growing up, and make my own path. I want to do things right.

The wood we are getting is from my in-laws wooded land. They have a lot of hardwood they harvest there. We also have a lot of downed trees on our new property. many piles of round logs just have been sitting in piles. The bark is wet, dirt sodden and much is soft or rotten at least an inch or so deep. This is the wood I have been using in my outdoor fire pit to combat the mosquitos. Using up cardboard to help smoke them out.

I’m glad that I’ve found in some posts the reccomendafion for over night burns to either pack the wood stove on top embers just prior to bedtime, or to fill it with rounds. Is this accurate?
Just fill the stove up with good dry wood get it up to temperature and shut the air back in a couple steps. Nothing special needs to be done.

Btw soft woods are perfectly fine to use as well. They also dry much faster they just aren't as dense so they have fewer BTUs per load of wood.
 
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begreen

Mooderator
Staff member
Nov 18, 2005
89,794
South Puget Sound, WA
This is a good website for wood stove information. If you go to the Videos page watch the Efficient Wood Stove Operation video. I think you will find some helpful tips on running a modern stove.

 

rosieXdox

New Member
Sep 29, 2021
43
new jersey
Thank you for the link. the videos are helpful. talking about heat cycles... i never heard that. very interesting. hopefully i’ll be able to put it all to good use