Cheap fractionating still

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Cheap fractionating still

Postby Seb » Wed Nov 21, 2007 1:29 pm

Hello, I live in the countryside of Brazil for 5 years, the country of cane ethanol.

Here making ethanol for your own use is allowed, but selling it is forbidden.

My plan is to disseminate very cheap ethanol stills around and supply my neighbors with cane mash. This is legal.

This is interesting for my neighbors as the ethanol will cost between 33 to 50% less that way. And 90% of the cars sold today in Brazil are Flex.

My point is to gather your opinions about my still project, made out of scrap material, mainly steel. No copper at all.

I will use a 200Litres steel barrel like everyone knows as a boiler:

Image

Under this barrel I will fix a steel plate so that the barrel can bear the high temperatures of dried cane fibre direct fire.

On the top I will put a 2" column full of SS scubbers until the condenser which will use a automotive radiator like this:

Image

This radiator avoids me to buy any copper (for a serpentine) and is quite efficient.
The radiator will be in a sealed steel box where the vapors coming from the column will circulate, and condensate.
Some of the liquid will go back to the column and some will be collected, like the Bokabob two cup fractionating still, depending on what %ABV is collected.

Let's get to the point: I will have 150 liters wash boiling in the barrel on one side and on the other side I have a very effective condenser. My questions are:
- what is the ideal height of the 2" column to collect pure ethanol in these conditions?
- Keeping in mind the volume of mash boiling, would you use a 3" column instead? If yes, what would be the ideal height?
- For those who already made some similar experiments, what is the average time necessary to collect the +/-17 litres of 85% ABV out of 150 liters of wash at 10%ABV?
- Eventhough the process is quite simple for the operator, what would you do to make it more simple?

No doubt that the still has a limited life, especially the boiler, but I will provide my neighbors with plans to repair it and to better it. My aim is to give them the opportunity to make their first shots.
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Postby Ricky » Wed Nov 21, 2007 4:23 pm

since you are making fuel if i was you i would look into denaturing what you make. since you are using steel and aluminum if some idiot decided to drink this stuff it could be ugly. just a little cya if you know what i mean. other than that i dont make fuel or much vodka so im not much help.
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yeh

Postby Uncle Jesse » Wed Nov 21, 2007 5:35 pm

Cheap but...that radiator will poison people if they drink the product so be certain they don't make that mistake.
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Postby pintoshine » Wed Nov 21, 2007 6:26 pm

I have a friend, who is strictly a fuel producer. His setup is similar to the setup you are suggesting except for a few items.
He made his condenser out of 1/2" EMT conduit. It only cost him $10 for 50'. He gas welded the 10' sections together. The 1/2" is actually slightly larger than 5/8" ID. He used a standard conduit bender to make his coil and used a 33 gallon barrel for his flake stand.
He fabricated his column out of 3" conduit and uses cut down and punched vegetable cans for his structured packing. They are tin plated and last two years or more. He used a standard zinc bulkhead coupler, designed for connecting to a panel box, for the the pipe to barrel connector.
His flake stand is mounted in higher than the column and he splits the output back to the middle of the column. This has to be the cheapest column still I have seen but it works well.
He denatures his alcohol as it comes off the still. It smels so bad no one would dare to try to drink it. I believe he is using some variation on methyl mercaptin(sp).

I was just wanting to illustrate the achievable budget fuel setup. His cut down, perforated chili cans for packing crack me up.
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Postby Seb » Thu Nov 22, 2007 1:48 am

To uncle Jesse and Ricky: Ethanol fuel is very common here as it sold at the service station. Everybody knows that it is harmful. The ethanol sold at the service station is not denatured.
Cachaça is so cheap (0.25usd/4cl at the bar) that nobody is poor enough to drink ethanol.

pintoshine wrote:I have a friend, who is strictly a fuel producer. His setup is similar to the setup you are suggesting except for a few items.
He made his condenser out of 1/2" EMT conduit. It only cost him $10 for 50'. He gas welded the 10' sections together. The 1/2" is actually slightly larger than 5/8" ID. He used a standard conduit bender to make his coil and used a 33 gallon barrel for his flake stand.
He fabricated his column out of 3" conduit and uses cut down and punched vegetable cans for his structured packing. They are tin plated and last two years or more. He used a standard zinc bulkhead coupler, designed for connecting to a panel box, for the the pipe to barrel connector.
His flake stand is mounted in higher than the column and he splits the output back to the middle of the column. This has to be the cheapest column still I have seen but it works well.
He denatures his alcohol as it comes off the still. It smels so bad no one would dare to try to drink it. I believe he is using some variation on methyl mercaptin(sp).

I was just wanting to illustrate the achievable budget fuel setup. His cut down, perforated chili cans for packing crack me up.


Do you have some pictures? I can't get this: "He used a standard zinc bulkhead coupler, designed for connecting to a panel box, for the the pipe to barrel connector.
His flake stand is mounted in higher than the column and he splits the output back to the middle of the column."

About the packing: at the scrap they have barrels of SS pig tails-like rests of a local SS industry. They give it to me for free. For the moment.

What is the average height of his 3" column? I've read that 2" column have to be shorter than 3" for the same results, the rule would be: multiplicate the diameter of the column by 10. Someone agrees?
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Re: Cheap fractionating still

Postby domer07 » Sat May 10, 2008 3:52 pm

I really like your business plan. Are you sure about the legality of it all?

Where would I find the exact lanuguage of the laws that allow you to do this? I have my own personal still and I would like to know exactly what the legal restrictions are in Brazil.

Many thanks.
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Re: Cheap fractionating still

Postby Hawke » Sat May 10, 2008 4:11 pm

My 3" column is 4 feet tall. With minimum packing it will produce product in the 85% range. Filled with structured copper packing, it will produce 93.5% from a 10% wash. Collection rate is only about 600ml an hour though.
85% seems like a pretty low target for fuel production. 1.5 litres of water for every 10 litres.
E-85 fuel is 85% ethinol of 96% purity or better and 15% petrol.
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Re: Cheap fractionating still

Postby Husker » Sun May 11, 2008 6:17 am

E85 is 85% ethanol of 99.8% or better (which is Expensive to produce), and 15% URG. If you try to make E85 with 96% ethanol, it will separate, unless a lot of some drying agent is used, such as isopropyl alcohol, but at 4% water, I am not sure iso will help that mix.

85% ethanol works fine in any flex fuel engine. It might (most likely will) require a small amount of lubricant (since ethanol does not lubricate). Other than that it will burn like E85, but in some ways better (and in some ways worse). The biggest con of watered 85%, is that it will have a harder time starting up at low temps. It will have problems vaporizing. Ethanol pulls a LOT of heat out of the engine to vaporize (as does the H2O). If the temp is not there, the ethanol will have a hard time (or will not) vaporizing.

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Re: Cheap fractionating still

Postby absinthe » Sun May 11, 2008 6:26 am

if your planing on running just ethanol not petrol then 80-85% is spot on it tends to run the best at this range so i have heard
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Re: Cheap fractionating still

Postby Husker » Sun May 11, 2008 8:02 am

yes, 85% does run better than 96 (or 100%). The water in there helps to smooth things out.

However, the concern when running ethanol by itself is scoring your cyl's and walls, and valve stems. Ethanol has no lubrication, and washes oil. Gas also washes oil, but it provides it's own lube.

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Re: Cheap fractionating still

Postby jfproductions602 » Sun May 11, 2008 11:18 am

From what I have researched Husker is exactly correct concerning ethanol damaging an engine if it is not vaporized before entering the cylinders. I plan to run it on a 4cyl throttle body injection, but I am switching to ethanol after warm-up and also made a "pre-heater" coming out of the thermostat housing for the ethanol to be heated before entering the injector. I'll let you know how it does if I can ever get the mash to ferment ! (part of the problems of being a newbie) I have also tossed around the idea of the HHO supplement to help it burn. Take care,
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Re: Cheap fractionating still

Postby Seb » Sun Nov 12, 2017 1:16 pm

I knew it I had registered in the past!
Now I just dig up this thread from 10 years ago as my goal remains the same, a cheap and user-friendly fuel ethanol still. The still I am projecting today is a bit different from what it was in 2007 tho. The boiler will remain a 55gal drum but it will be laid on its side and heated at a place with no welding so it will last longer. Also, I won't use a car radiator anymore. Nowadays you can find and coil 3/8 aluminium tube which is cheaper than a car radiator, especially if I want to replicate the still and therefore always need the same item which would oblige me to buy brand new radiators.

Sorry Hawke, I read your post really late but that part is quite promising:
My 3" column is 4 feet tall. With minimum packing it will produce product in the 85% range. Filled with structured copper packing, it will produce 93.5% from a 10% wash. Collection rate is only about 600ml an hour though.


Here you can run your car both on pure 96% ethanol or gasoline or by mixing both (no matter how much of both) which is said to be better, at least a bit of gasoline to lubricate the engine. The car has the electronics to check what you have in your tank and run the engine accordingly.

Thanks to all of you for your replies. Internet is really a wonderful thing. I will feed this thread in the next weeks.
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Re: Cheap fractionating still

Postby Kareltje » Sun Nov 12, 2017 3:49 pm

But what happened to your old plans??
And could you please post some pictures?
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Re: Cheap fractionating still

Postby Seb » Mon Nov 13, 2017 9:18 am

My old plans had its pictures removed from the thread. One pic was this basic plan:
Cheapo.JPG
Ladies and gentlemen, the Cheapo
Cheapo.JPG (7.84 KiB) Viewed 467 times

But since this is a fossilized thread it's normal. I will post new pics soon since the Cheapo will not look like that any more.
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Re: Cheap fractionating still

Postby Seb » Sat Nov 18, 2017 3:13 am

Good morning gentlemen.
I wish the still to be cheap and cost efficient because it will be used in small farms, mostly as a hobby that fuels the car of the family. Nowadays most cars run with ethanol and engines can run with as low as 85% ABV. The wort will be made of cane, that's the obvious choice.
Boiler:
I plan to use a regular 55gal drum as a boiler. It will lie on its side with some fire below it. The fire of the cane plant that was previously juiced and put to dry for some days. As there is no welding on the sides of the drum it will last longer. Also, when making beer I already heated such a drum (SS) in the stand up position, with a nice big paella burner but it took 2 hours and a half only to reach 80ºC/176F when full of wort. That's the other reason. The fireplace and the drum would have to be placed on the bottom of a wall to allow the installation of the rest of the still.
Column:
The 2 inches hole of the laid drum will of course be placed above the liquid level in the drum. The drum is full at only 3/4 = 40 gal of wort. By means of 2" to 3" adapter the column starts there and will be made of semi-rigid exhaust duct of 3 inches in diameter. I have no choice, duct starts at 3" and steel tubes and connections would be too expensive and require a guy for installation/welding. When you visualize it, at least a part of the column has to be parallel to the ground and then go up and perpendicular to the condenser system. I liked the post about glass marbles and I consider to pack the upper part of the column with them. I believe that the aluminium duct can hold and stand them if properly fixed on the wall. Probably in a section of the duct that remained not extended, maybe it's not even necessary. A grid would hold them down. Now I have some questions for those who have been there:
- Knowing that the still will be run by fire and the wort will eventually boil a lot, what is your opinion about insulating or not insulating the whole column?
- The column will have a L shape. The part just after the boiler 2" hole has to remain empty until meeting the grid of the marbles packed section. How tall would you make the column as a whole? How long would you make the empty section and the glass marble packed section?
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Re: Cheap fractionating still

Postby jb-texshine » Sat Nov 18, 2017 6:36 am

Brazil,right? Isn't there a lot of copper mining there? Building with copper and soldering can be easy.
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Re: Cheap fractionating still

Postby Seb » Sat Nov 18, 2017 7:24 am

jb-texshine wrote:Brazil,right? Isn't there a lot of copper mining there? Building with copper and soldering can be easy.


No. Copper is even more expensive that everywhere else. Such a still would be stolen within weeks if let alone in the outside.
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Re: Cheap fractionating still

Postby jb-texshine » Sat Nov 18, 2017 11:52 am

Seb wrote:
jb-texshine wrote:Brazil,right? Isn't there a lot of copper mining there? Building with copper and soldering can be easy.


No. Copper is even more expensive that everywhere else. Such a still would be stolen within weeks if let alone in the outside.

Aaah.
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Re: Cheap fractionating still

Postby Seb » Tue Nov 21, 2017 1:36 pm

The column packed and non-packed section are making me suffer.
I am considering the general rule that the ideal reflux column has a height to diameter ratio of 20:1. Knowing that the drum that I will use as a boiler has a 2 inches hole, in a perfect world I would naturally use a 40" packed and insulated column on top of my boiler and the 20:1 is respected.
But my boiler is ...1. laid on its side; 2. it's 55 gallons and 3. it will boil on direct fire with a bit less control than modern burners... Because of its horizontal position I have to use semi-rigid duct. I am reluctant in using only a 2" duct. I feel it's too small.
I am thinking about using a larger duct, for example 4" in diameter (+an adapter 2" to 4" at the exit of the drum) and to leave the first 2 feet non insulated and unpacked and then, when the column is eventually straight up, pack the column for 2 feet until the condenser. I feel it's safer to use larger duct to cope with the dimensions of the boiler - and to leave half of it empty and "cold" to calm down the possible excesses of vapors. Am I right in doing that? What would you do? Observations and suggestions welcome.
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Re: Cheap fractionating still

Postby Kareltje » Tue Nov 21, 2017 3:48 pm

jb-texshine wrote:
Seb wrote:
jb-texshine wrote:Brazil,right? Isn't there a lot of copper mining there? Building with copper and soldering can be easy.


No. Copper is even more expensive that everywhere else. Such a still would be stolen within weeks if let alone in the outside.

Aaah.
Copper mining is not nearly the same as copper making, let alone working it.
Copper mining produces copper ore. The landscape is dug out, the soil or subsoil is worked to produce a great lot of rubbish and a rather small amount of copper ore. A winnable coppersource contains about 2 % (sic!) of copper.
This copper ore is then transported to factories that separate the copper from the other elements. The main copper ores are oxides and sulfides.

But the main point is: the copper is mined in a country that is destroyed by the mining, then sold for a low price to a country/company that works the ore into a usable metal which then is sold for high price to the country that originally supplied the copper ore.
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Re: Cheap fractionating still

Postby Seb » Wed Nov 22, 2017 1:17 am

which then is sold for high price to the country that originally supplied the copper ore.
... it's true. And it's a shame. Now what about my column?
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Re: Cheap fractionating still

Postby jb-texshine » Thu Nov 23, 2017 2:50 am

Seb wrote:
which then is sold for high price to the country that originally supplied the copper ore.
... it's true. And it's a shame. Now what about my column?

Not for drinking purposes is actually harder to do on limited resources than for drinking.
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Re: Cheap fractionating still

Postby Yummyrum » Thu Nov 23, 2017 6:33 am

Seb
If you intend to fire this still with burning cane debis etc I am imagining that the heat will vary quite substantially and subsequently the vapour flow will up and down like a yo-yo .
I would recommend you make a VM ( Vapour Management ) still head as it will give much more consistant ABV output than a coolant or Liquid management still head .

Regarding stills for fuel:
To be honest I get an uneasy feeling about stills being made that are not suitable for drinking alcohol production . There is always the possibility that someone will use it for that purpose or others may copy it thinking that it is an acceptable design .The lead soldered radiator is exactly the sort of thing the authorities love as a reason to strengthen the case against home distilling .
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Re: Cheap fractionating still

Postby FullySilenced » Thu Nov 23, 2017 4:30 pm

SEB look at the basic still designs in my signature line... i think you will find references in Hooklines drawing giving you column heights and so forth...

have fun, read a lot... DO NOT LET ANYONE DRINK YOUR FINISHED PRODUCT...

happy stillin,

FS

here is a link in case your can't find it: viewtopic.php?f=1&t=18873

You may also want to look at DAD300's simple still design
Do it Safely read The safety section: viewforum.php?f=33
New Distillers Reading: viewforum.php?f=46
Hookline's Basic Still Designs: viewtopic.php?f=1&t=18873
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Re: Cheap fractionating still

Postby Seb » Fri Nov 24, 2017 2:15 am

I will read everything, fullysilenced.

Yummyrum: There won't be any lead soldered radiator in my design, no lead at all. VM for a more constant ABV than with a LM? It's not obvious to me, can you tell me why?

Guys, you all remind me to be careful and make sure nobody will drink the ethanol that will be produced with the still. In Brazil, you have at least 2 pumps at every gas station: pure ethanol and gasoline. Ethanol costs today 2,40 reals which is $0.74 per litre. I know it I run on ethanol. I am sure it is not even denatured. It is cheap and available everywhere, literally at every corner. I really think those who are crazy enough to drink ethanol ... are already dead by now. The drunks in the street are well aware that it makes you blind and they don't touch it. More important, cheap spirits at the supermarket are about the same price for the same quantity. If someone did a dangerous booze with the still, it would make a terrible booze, nobody would go beyond tasting it. Finally, there is no reports of people drinking gas station ethanol, and I didn't hear of anybody becoming blind because of bad booze nowadays. In a word, nobody would drink that and nobody would take the risk to poison someone else that way. Because it would just be stupid.
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Re: Cheap fractionating still

Postby yakattack » Fri Nov 24, 2017 12:50 pm

Never underestimate the power of stupid people
HDNB wrote: The trick here is to learn what leads to a stalled mash....and quit doing that.
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Re: Cheap fractionating still

Postby jb-texshine » Fri Nov 24, 2017 1:29 pm

Honestly, once you disseminate these stills through your community you lose control of what others will or won't do with the product. That is why your not getting any help.
Also ,you speak of ethanol fuel as if it is different than alcohol we drink. It's not. Whiskey=ethanol,vodka=ethanol,rum of any variety=ethanol. The difference is that the fuel ethanol is mixed with gas to denature it so it won't be drank AND as a lubricant.
That having been said, I'll offer this advice on still choices for your original intent.
Go with the bokakob. That way it is safe for everyone. People and cars alike.
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Re: Cheap fractionating still

Postby Seb » Sat Nov 25, 2017 4:28 am

jb-texshine wrote:The difference is that the fuel ethanol is mixed with gas to denature it so it won't be drank AND as a lubricant.
Here it's pure 96%ABV, it's not mixed with gasoline. That's why if you run mostly on ethanol, it is always advised to put at least some cents of gasoline when you are at the gas station. It's not even denatured by means of bittering agents. If the big tanks of the gas stations weren't used sometimes for gasoline, some other times for ethanol - and therefore there are always traces of gasoline in the ethanol - I am quite sure I could rectify it. I won't try that. I am just saying.

jb-texshine wrote: Go with the bokakob. That way it is safe for everyone. People and cars alike.
The choice is either a bokabob or a complicated rectifying device with plates or bubble plates. Yes I'll go for the Bokabob reflux. I made this still in copper but I still have to finish it, the column is made out of an old copper fire hose I bought in Argentina. I still have to figure out how to fix it to the keg. :? Also, the condenser is taller than the column.

20171125_101901_resized.jpg


For the fuel alcohol still I am planning, yes, I will do it using the same principle.
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Re: Cheap fractionating still

Postby Cu29er » Sat Nov 25, 2017 6:30 am

The Boka is what you want, to get as high ABV as your target.

Your build seems much more complicated than necessary. Try for a taller stack and shorter condenser.
Straight pipe up (stainless automotive exhaust pipe?), two plates sawed in at an angle and welded, small (copper) coil inside the top with some packing around it to diffuse the chill (3ft of 1/4in copper coiled in 6 inches so not much needed and this puts copper hidden in the system), take off line down with sensitive valve as high as you can reach comfortably (faster feedback when adjusting), sufficient but not too tight SS packing.

A boka takes more attention than a pot-type to operate because you are managing cooling water and the valve to maintain output. Like driving with both your feet one each on the brake and accelerator.

However, be cautious with the packing. Packing can plug and then you have a pressure explosion risk. If the pot is over filled it will expand and push up into the packing and plug it. Heat too high and it will plug. Lots of air space over the boiling mash is best, and mash that is strained of debris. Shielding.

Remember that you will have farmers running it that are busy. They will try to boost the fill, boost the heat, and try to cut their time, they may have their wife or teen kid run it because they have equipment down to repair, animals to take care of, and need to get the harvest in before the coming storms. So make it safe and easy to run.

.
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Re: Cheap fractionating still

Postby Yummyrum » Sun Nov 26, 2017 2:20 am

Seb wrote: VM for a more constant ABV than with a LM? It's not obvious to me, can you tell me why?


OK I'll try .
1) You have a reflux still . It works by needing reflux falling back through the packing to increase the purity .
The purity that you get is determined by the ratio of how much you take off verses how much return down the packing ......its called the the reflux ratio .CM , VM , LM ....its all the same at this point .

2) A LM ( Liquid Management ) still controls ( Manages) Reflux by adjusting how much condensed liquid you take off , this is usually set by a needle valve , the rest is returned as reflux .
OK that makes sense so whats the issue .
Stick some more wood on the fire , the boiler starts to makes more vapour , You are still taking off the same amount of product but suddenly there is heaps more overflowing as reflux .....and the purity goes up .

Guess what happens when the fire dies down .....less vapour ,........ you are still taking off the same amount set by the needle valve , but there is less reflux and the purity takes a dive .

3) So why is VM better ? in a Vapour management still , the reflux ratio is set by how open the valve is . This sets the reflux ratio ..... or the proportion of vapour that is taken off as product verses how much is condensed and returned as reflux . If the valve lets 10% of the vapour exit as product then the other 90% is reflux .

So how is it better than LM ?
Well if you stick some more wood on the fire , you get more vapour . 10% is still going to exit as product and 90% is still going to be refluxed so the reflux ratio hasn't changed ......therefore the purity hasn''t changed either .

Same thing when the fire dies down , less vapour ...the split is still the same ...the reflux ratio is still the same .....the purity is still the same .
The only thing that changes is the output rate .....but at least it is at a constant purity or ABV .

And I know this from personal experience here as our electricity goes up and down like a Yo-Yo . I built a LM/VM head and I never use it in LM anymore as VM is much more stable with a varying power source ......like a wood fired boiler :thumbup:

So I can see why folk are suggesting Bokas as they are under normal stable powering conditions a good still but in your circumstances I think VM is the go :eugeek:
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