Stove of all kinds adapted hair cell

[Grelinette]

Hello everybody

Little feedback ...

After buying a small cast iron wood stove to replace the old sheet metal insert we had, I reactivate this subject to tell you about a funny mishap!

The replacement of the insert was done in a mess and shortly after the first outbreaks, a viscous black liquid started to flow along the smoke evacuation tubes:


I had swept the chimney tubes well and I reinstalled them as they were of origin, namely nested male part in bottom and female part in top.
That seemed logical because the sealing is not perfect, and this assembly seemed to me to avoid that fumes leave the conduit and pass in the part.

After information taken on the net, it turns out that the conduits were laid upside down: the female part must be at the bottom, and the male part at the top to avoid that the condensation flows loaded in bister pass through the sockets and flow outside the duct, exactly as shown in the photos.

Preference is therefore given to the condensate drips which descend to the rising smoke flows, which cannot escape from the duct thanks to the upward suction.

By cons I do not understand why I have not had any flow for several years, and just by changing the pan, the phenomenon occurred so quickly with so much importance! ...

The only differences that can explain this phenomenon are that:

- on the one hand, the new stove is made of cast iron, therefore with a mass heating effect which restores the heat gradually and longer (the previous one was made of sheet metal: the heat build-up was very rapid and the reverse too),

- on the other hand, it seems that the phenomenon of drips is accentuated when I burn locust logs ("false-accacia"); these logs having only one year of drying but nevertheless appear very dry. It is all the more curious that I have often burned damp wood with the previous insert, without having any sag!

Do you have an explanation for this important new phenomenon?

Addition: thinking about the problem, I said to myself that by reversing the direction of connection of the pipes (male part at the top and female at the bottom), the oozing of bistre will go back down into the stove and will clog it more. It is therefore not necessarily the ideal solution!
It would be necessary to put a part in T or in Y which recovers this liquid bistre before it returns to the stove.

[Macro]

On any smoke pipe actually the nesting is done in reverse of the flow of the smoke to avoid the flow of condensate along the pipes the smoke leaks are supposed nonexistent because of the draft (the pipe is in depression).
As for your flows the locust is a very hard wood which requires a longer drying and your cast iron stove which now turns at a slower speed compared to your old sheet metal are the ideal conditions to have ... My ex tenant who heated his main room with his old wood stove (a small fire all day long) had his stove duct swept two or three times a season. Yet it only burned copse of very dry oak and coal of my size of linden trees that it fagot and dried ...

You can always put a tee with a stopper and a redustion funnel with a receptacle for the tar which will sink down..But not too big the drain hole otherwise it will decrease the draft of your stove and as you will create a cold zone the drainage hole will plug up fairly quickly ...

[Did67]

In my opinion :

1) It is rather a good sign: your stove "squeezes" the fumes better, which leave less hot; suddenly, the duct, less hot, condenses ... So better performance.

2) To which is undoubtedly added the phenomenon evoked by macro: regulation by the pull, longer outbreaks, less violent ... So fumes less hot. So better performance. But therefore condensation.

3) It is also very worrying. Because the accumulation of bistre (pasty mixture of carbon particles and condensate) creates a risk of a chimney fire. Once dried, this bistre becomes a fuel. One day or another, for example after lighting, you leave a little too much draft, the flames, too bright, rise in the duct; they lick this brown; the bistre, dry, ignites; this "fire front" goes up, without you being able to stop it ...

Wanting to "contain" this flow phenomenon is in itself a bad idea (apart from aesthetic reasons): it is necessary to limit condensations.

And if you regulate your stove by draft, use only dry wood.

And of course, sweep it right, conduit and bushel!

Otherwise, increased risk of chimney fire!

[Grelinette]

Hello and thank you for your explanations.

Obviously, as you explain, the increased performance of this new wood stove have generated this problem of condensation and significant sagging of viscous bister ... as what, better performance (with tubes laid upside down) can also cause inconvenience!

To come back to these flowings of bisters, given the quantities that flowed in only a few hours of use, it seems to me necessary to prevent them from falling back into the stove or accumulating at the base of the duct.
(After each outbreak there was the equivalent of a 20 cl glass in the form of a small puddle on the floor and on the stove, not counting the drops which have caramelized along the duct).

I imagine that these volumes will quickly accumulate then dry and present a risk of chimney fires, even if a priori a chimney fire does not seem dangerous because I extended the exhaust duct with metal tubes until when leaving the roof: the fire should be confined to the duct.

Moreover, this liquid bistre, logically, descends into the stove and must partly ignite and therefore decrease gradually? ...

Here's what I plan to do if you think it's worth it:

At the base of the Y connector, which will be closed by a plug to avoid damaging the draft, I will place a container that will collect the flowing liquid bistre.

Sounds simple to do, but is it really useful? ...

[Did67]

1) I'm not sure you will easily find a waterproof "plug"!

2) But indeed, once returned in the right direction, you must collect the condensate. For stainless steel casings, there is a "pee" specially for that. A kind of semi-hemispherical plug with a small tube in the middle.

This should exist in multiple diameters and be compatible.

3) The most elegant would be to extend it in a container, with the nozzle always below the water level so that the gases (room air or fumes) cannot circulate.

But these assemblies should not obscure the real problem, which is not dry enough wood:

- which means condensate, as we can see
- but also loss of yield (the energy released by combustion will first, in the fire itself, be used to evaporate all this water instead of being released to heat)
- combustion will be cooler, therefore less clean; outside, in calm weather, it must smell of the "scout fire", the one that smokes and stings the eyes! And the gas that stings is not pretty (or clean-clean) ... In a sort of "bluish" cloud

[chatelot16]

water consumes energy to evaporate, but if it were only that, it would not be a very serious loss of yield ... for example wood which has finished dried and wet then burns very well

the problem of green or not dry enough wood is its way of forming volatile products which do not burn and take tar in the chimney: it is worse than energy to vaporize water, it is fuel lost ... and possibly accumulated in the chimney to make a chimney fire

the drying of the wood is very slow when it is left in a log of 1m ... it only dries by the 2 ends

it would be much better to cut the wood in 50 33 or 25 from the start so that it dries faster ... alas the way to sell the wood in stere is not favorable: when you cut the wood it ranks better and reduce the volume ... so the sellers of wood prefer to sell it in 1m to make more volume

I do the opposite, I pass everything to the crusher and it dries much faster ... 2 months after grinding it burns as well as 1m logs which are 2 years old

[Ahmed]

The above comments contain some inaccuracies.
Acacia has the property of burning easily after only one year of natural drying, unlike other species; this does not mean that combustion takes place in good conditions and two years of drying are essential.

Chatelot, you write:

alas, the way to sell wood in stere is not favorable: when you cut the wood it ranks better and reduces the volume ... so the sellers of wood prefer to sell it in 1m to make more volume.

The cubic meter is the volume of an apparent cubic meter of log stacked in 1 M long, so it cannot measure stacks of logs longer or shorter than the one used to define it.
Consequently, to estimate a pile of logs of a length different from the basic unit (1 M), it is necessary to use a coefficient which takes into account this variation in volume: 0,8 for 50 cm, 0,70, 33 for 5 cm, for example. These coefficients provide stere equivalents in one direction, for example 4 stere will transform into a stack of 3 M4 sawn in half; and conversely, these 3 M50 of logs in 5 cm will give 1,25 cubic meters, once this figure multiplied by 33. For the 0,7 cm, use the coeff. 1,43 in one direction and XNUMX in the other.
Obviously, these are approximate values ​​because an exact calculation does not provide more precise results than the initial data and it is notable that the real volume of a stere depends on the straightness of the wood and the diameter of the logs.
According to Adème, the most advantageous stere for the user would consist of large straight woods, which is not entirely accurate: the theoretical optimum is reached with a mixture of large wood mixed with small woods which fill the interstices .

If some firewood suppliers prefer a particular length, it is according to their equipment; handling of the M is very different from that of short length ...

Grelinette, your stove may have double combustion, the gas path before evacuation is far too weak to ensure perfect combustion.

[chatelot16]

Ahmed, you confirm what I mean ... the sellers of wood always have the same problem! deliver 10 wooden stere that the customer cuts and stores well and there is only 8 m3 left so he believes he is stolen ... and it is very difficult to explain the coeficient yet well known to someone who believes himself defrauded

the sale of wood is complicated ... measured by the kg there would be no change when you cut into pieces, but selling by the kg would be crime-prone, the wetter it would be the heavier it would be ... dry well

sale by kg with humidity measurement to correct the price ... impossible, firstly a reliable meager of humidity costs too much, secondly the humidity of a pile of wood is never homogeneous ... difficult to collect representative sample

my favorite solution, grind everything into wafers, a little solves the problem of volume measurement, and also solves the problem of humidity measurement ... easy to shovel with the shovel to make an average sample

[Grelinette]

Hello and thank you for your comments,

To start, I abandon my plan to put a Y at the stove outlet to prevent the condensate from falling back into the stove.
This cost € 50 and the result is not guaranteed. The seller also told me that the condensate drips that will come back down will eventually burn ...

Regarding the quality of wood and its drying, this is a recurring problem that every stove user knows. In my case, I mainly use dead wood that I cut on the land of my home, there is mainly pine and oak, and the quality of this wood is very variable in terms of drying, content tannin for oak or resin for pine which is very variable depending on the season when the tree is dead or has been cut.
For example, a dead pine in spring is stuffed with resin, easy to light and burns well, if not too much, but fouls the chimney.

Otherwise, when I talk to my neighbors who buy their wood from a supplier, many complain of deliveries of wood that is not dry enough. It seems that many wood suppliers work just in time: they quickly respond to demand by skipping the drying of wood. Probably because they have a hard time finding quality dry wood themselves, because they have no room to store wood to let it dry for a long time, or because young wood is less expensive so their margin is larger, etc ...
Currently, it's a bit of a lottery when you get wood delivered: lack of criteria or label, you never know what to expect ... and the chubby on the square rub their hands.

Heating with wood is therefore not so easy to implement, and some return to fuel or electricity because it is safer and simpler (and "cleaner" for them because there is also constraint of almost daily cleaning of the stove and ash).

Grelinette, your stove may have double combustion, the gas path before evacuation is far too weak to ensure perfect combustion.

Hello Ahmed, I don't understand what you mean!
Between the stove and the duct outlet on the roof, there is an S-connector and 4 meters of nested tubes. A priori that is enough, the old insert did not pose a draft problem, apart from that of heating quickly and cooling quickly.

Moreover, another small drawback with this new wood stove is that when the fire starts there is a noise of air suction with the draft, like a little mermaid!

That said, if the length of the duct is insufficient, I can add 1 tube of 1 m above the roof; I still have a tube and I will still put it down to see if there is a difference.

Good day to all

(PS: Ahmed, where are you with your tool project with compression / tension spring?)

[hic]

hi Grelinette

fouling of the ducts = poor combustion

And if . . . ?
Your dry pine burns poorly
He kissed massively and choked
(despite your double combustion stove)

As we find the same problem as with fireplaces that operate at low power,
1/4 power
This divides the yield by 2.
*** https://www.econologie.com/forums/le-rendeme ... 14300.html ***

In these conditions,
boosting with an air turbine is economically viable,
less waste less pollution.

Why think more?
It is a one-stop solution for a general problem.