Wood stove heat

PCTREE said:
I’ve always been interested in running PEX pipe through a pile of chips and heating with the water. Lots of wasted heat there. I really don’t understand why chips aren’t gassified leaving the carbon as char in power plants and such. Carbon negative and a great byproduct
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there is guy here in detroit that has a system like that for his greenhouse.

Compost heater - Wikipedia

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cory said:
Tons of good info here, thanks.

FTR, double Eco Fans on the stove top have been working very well, shoulda done it a while ago. 8)
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Tons of ........info here. Best to check with with a pro or look up your actual local code for your area if you want to be safe. Hearth.com is a excellent online resource/forum of wood burning nuts.

In my area stovepipe(not chimney) is single wall or double wall. The single wall is 18" clearance to combustibles, the double wall is certified 6" clearance. Double wall obviously has greater insulating value and keeps the creosote down and the draft up, but you get less heat off of it. The heat ideally should come off your stove not your pipe and chimney. That said I run single wall in my house and my shop, quite a run of it in my shop too 12-14' off the top of my head. General rule of thumb is to match the stovepipe and subsequent chimney size to the to whatever size is coming off your stove and not to change up or down. If you have long runs of single wall stovepipe you can create some creosote concerns for your system by scavenging to much heat off your exhaust so that the nastys solidify in your pipe/chimney/cap. Also can weaken draft so that the stove doesn't burn as efficiently.

Where the stovepipe reaches the ceiling or goes through a wall you will use a certified adapter(we are talking all metal systems here not masonry chimneys) and this is the point where thenstovepipe ends and the chimney pipe starts. Double wall stainless chimney pipe is the industry standard , triple wall don't be fooled by the extra wall double wall chimney pipe is all certified to 2" clearance and atleast one brand is certified to 1". Forgotten which off the top of my head.

If your stove is certified it'll have a data plate on it which will list all of its clearances, usually on the back somewhere if it doesn't it needs to be treated as a uncertified stove which in my locale is 4' clearance all around 5' on to

In my locale and most clearances can be reduced for stoves and stovepipe by creating shielding which is a fire proof material set on 1" standoffs with clearances around the edges for air movement etc, etc and generally reduce clearances by 50%.

But probably the most important thing with a wood burning system is using it and maintaining it properly. I've been burning wood most all my life with no issue because I burn cured wood at the proper temperatures and maintain a clean stovepipe and chimney. I literally cannot have a chimney fire because the nescessary fuel build up just doesn't exist in my pipe/chimneys to support one.

If you are burning this stove in your shop just be aware of fumes, often and to code up here woodstoves in shops need to be elevated somewhat(can't recall the actual code requirement off the top of my head) to help to avoid any low collection of fumes. When you put it in and set it up, check it often(pipe, chimney, cap)to determine how it's working, if something isn't happening properly or set up right systems can foul up fast. That's dangerous.

Lastly enjoy! I love having wood heat, espescially in the shop, beers, projects ahhh, the best times!
 
I am just waiting on the cap that is hopefully just a week out. I have, like you 12-14'+, of single wall to 9 feet of class A double wall insulated going thru the roof, silicone weather seal, and supports.
One thing I did do is neck it down from 8" single wall to 6" at the insulated pipe. I guess I'll see how it works. :|: Hopefully it will be ok IDK. Probably 26'ish of total stack height so I'm hoping it will draw just fine.
 
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I bet it will pull fine espescially with that height. Is it a straight up run off the stove? It is not recommended to downsize the flue and here that wouldn't meet code(dont know how that would,work where you are or if it's a concern at all). If it's a smoky, stubborn, biatch espescially to get going........well you'll know why! My gut says it'll work, just monitor for buildup espescially where the restriction occurs.

The different diameter runs will make cleaning a bit more challenging. I'd recommend looking into a soot eater. It's essentially rods that attach to a drill and a head that spins with literally weed whipper lines in it. This type of cleaning tool is superior to fitted brushes IMO. I used a pro version of it when I was cleaning chimneys and did definitive testing to satisfy myself that it cleans far more effectively. As in I could brush a chimney and the weed whip it and get measurably more soot/creosote out whereas done in reverse the brush would get next to nothing after a whipping. This soot eater system will also negotiate the different diameters with ease, just make sure the weed whipped strands are long enough to clean the 8" and they'll clean the 6" fine too.
 
Straight run. It won't be a big deal to change it out later if need be. The neck down is where the insulated pipe begins 15' up. Thanks for the Soot Eater tip.
 
Anybody see a problem running a wood stove without a cap? It will be short term as I want heat now, installing today, but cap is backordered two weeks.
 
flushcut said:
Anybody see a problem running a wood stove without a cap? It will be short term as I want heat now, installing today, but cap is backordered two weeks.
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Don't you wish that sometimes there was a Tree House signal, a la the bat signal?

One day I was able to ask Peter/ Raj
an electricity/ electric motor question about my old, now sold, grinder.

Sometimes, I wish I could get some fast, expert feedback on stuff from the House!
 
You could fab up a temp cap. Years ago I had my bud fab one while I was working on another project. He cut the bottom out of a metal driveway sealer bucket. Cut it and formed it into a cone and made some mounting brackets. I started to give him hell on how bad it looked. It will work won't it was his reply. Yeah, it did for years. Cheap help.
 
We took the cap off our chimney pipe...hasn't been on for about five years, stove works fine, better than with it on, no issues with rain, but then we don't get rain for days on end
 
Alright, I've found some other stoves, and might be buying one today. Anyone heard of a Vermont castings downdrafter? The one in question has both a blower and a water coil, so with that i can definitely heat my whole house. I guess it was an early attempt to be efficient, cause you force the smoke down through the charcoal bed, then introduce secondary air to fully combust. I'm pretty excited about buying this one if there's no major known faults, so help please.
 
Thats exciting! Good luck with it!

Are ya all good with wood for this season?
 
Oh i gotta call him up yet, but I've been looking. Yeah a buddy came and split up a bunch i had laying around, so I'm set, just need a stove or insert.
 
flushcut said:
Anybody see a problem running a wood stove without a cap? It will be short term as I want heat now, installing today, but cap is backordered two weeks.
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100% zero issue to run without it. It isn't recommended or to code. But I haven't had a cap on my shop system for 10 years I've been here and who knows how long before that. The rain keeps the pipe spotless because I burn so efficiently, it washes the soot that does form down the pipe.
 
Tree09 said:
Alright, I've found some other stoves, and might be buying one today. Anyone heard of a Vermont castings downdrafter? The one in question has both a blower and a water coil, so with that i can definitely heat my whole house. I guess it was an early attempt to be efficient, cause you force the smoke down through the charcoal bed, then introduce secondary air to fully combust. I'm pretty excited about buying this one if there's no major known faults, so help please.
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Not familiar at all with that stove or VC in general because stoves are heavy it's common for certain brands to be predominant nearest where they are manufactured. Some brands are widespread but many are not. Be cautious of stoves/systems that scavenge heat by various methods like fans or heat exchanger setups. It's usually not a great thing for the chimney and can cause rapid/bad creosote buildup. I don't use a fan whatsoever on my basement stove but it is a highly convective steel stove, so I'm not looking to scavenge more heat off of it. Heat in the pipe/chimney is important to keep a good velocity(draft) and keep the formation of bad creosote(the sticky tar like mind) down. There is no magic bullet with wood stoves. Wood has a certain amount of btus (heat potential) in it and can be extracted many different ways. The goal is to get heat and keep the chimney clean. I run all steel stoves/inserts and well insulated chimneys. I use thermometers to monitor stovetop and pipe temperatures and heat entirely with wood with zero closecalls or concern about creating a unsafe chimney. I do have a fan on my insert and on my shop woodstove. Inserts usually need a fan to get the heat into the room efficiently but use it with caution, don't run it until the insert is well warmed up and don't run it when reloading or settling in a new load of wood.

Nearly 100% of modern woodstoves that employ any kind of reburn or secondary ignition system are meant to be burned in cycles. This means once the fire is established it's meant to be loaded right up and air control opened right up and allowed to run right up to near its max temperatures charring the load of wood. This does a few things. It gets lots of heat into the pipe/chimney creating good velocity, it also gets the stove up to a good temperature to support secondary ignition of the bad creosote so it is burned off in the stove instead of deposited in your chimney. Good chimney velocity/temp also means that as some (creosote) invariably gets through the stove it has a good chance of exiting the chimney before condensing. When the load of wood is first being burned is when nearly all of the bad creosote will be released, once the wood has burned up good and really charred very little more bad creosote will be released. So after the load has been burned on high for a bit (timeline is determined by many variables such as wood type, size of load, how many and how hot of coals was the load put onto, stove type, chimney setup, etc, etc) the air gets cutback and cutback until its often choked off to its lowest setting. This forces the stove to draw air in through its secondary system, many secondary reburn stoves the 'reburn' is visible and once a load is first settled in this should be very robust. The stove is 'burning' it's own exhaust at this point. This is super efficient and super clean and is the goal to achieving good heat and long burn times. Modern stoves are not meant to have a stick tossed on here and there willy nilly to keep it topped up. This will be inefficient at best and a smokey disaster creating lots of creosote at worst. It's a cycle and the length of that cycle again has near endless variables. If secondary ignition isn't achieved or lost at some point the air should be bumped open some to get the stove up to temp. One of the most dangerous things you can do is burn a modern stove to cool. Secondary ignition must be achieved for efficiency and safety(keeping the pipe/chimney clean).

Whatever setup you have I cannot recommend enough the use of thermometers. Yes I can burn a stove fine without thermometers, but I can burn it like a friggin' expert boss with one, and much more easily.
 
The most common reburn system is a 'baffle' setup in the ceiling of the stove. This will often be tubes with holes or a plate of some sort with holes in it and it forces the smoke to route around it usually to the front of the stove. If you have such a stove and you never see flames shooting off of the holes like little flame throwers you are not getting the stove hot enough.

I'll add that when you burn in a proper cycle as the wood has turned completely to coals it's fine for the temp to drop off some at this point as nearly all of the volatile nasty type creosote is long gone by this point. Once those coals are settled in they can glow/burn in there as long as you want, or if you are needing more heat again sooner just bump the air open some and burn them down faster. You should always be loading onto coals, not adding a stick as it will fit or just here there or whenever you happen to be walking by.
 
I've read up on them, it has a bypass baffle up top that is used only when charging/ lighting it off, it's usually closed, forcing the smoke back down through the bed of coals. The air intake is designed to fuel both the wood bed and the secondary burn. Basically its a downdraft gasifier designed to burn logs. Everything I've read on them is basically they won't leave any creosote, but they take a bit to learn how to operate it best. Basically a gasifier and a Franklin stove. Thanks Justin, just what i was hoping to find here.

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[QUOTE="squisher, post: 1027685, member: Whatever setup you have I cannot recommend enough the use of thermometers. Yes I can burn a stove fine without thermometers, but I can burn it like a friggin' expert boss with one, and much more easily.
[/QUOTE]
I have (2) 3 gallon stainless steel tanks filled with water on my stove ... I use an aquarium thermometer in one of them to monitor the water temperature. This allows me to precisely monitor the stoves output to the tenth of 1 degree F ... I’ve found this method to be most accurate , ymmv
 
I've never cleaned my chimney, but I went overkill when I built. I had my mason build the chimney with 13" flue liners, and with a 6" stove pipe feeding it, it just crusts, breaks free, repeat. I haven't looked down it in several years, but it's never come close to building up much at all. Every year I rake a good pile of gunk out of the clean-out at the bottom.
 
Not super familiar with stove models, but ive heard good things about Vermont castings. Reasonably common around here and noone has said "f those stoves"
 
squisher said:
The most common reburn system is a 'baffle' setup in the ceiling of the stove. This will often be tubes with holes or a plate of some sort with holes in it and it forces the smoke to route around it usually to the front of the stove. If you have such a stove and you never see flames shooting off of the holes like little flame throwers you are not getting the stove hot enough.
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That's the kind I have, its fun to watch the little flame throwers. Now I know what they are for.

Good info re adding fuel, didn't know that either.
 
Going to look/ buy it this afternoon, pics to follow. Im hoping this is gonna be exactly what i was looking for. Laying in bed last night just getting pissed everytime the furnace kicked on :lol:
 
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