TIS Uni wood boilers

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Do you have any pictures of the combustion chamber(s)? Trying to determine if these are downdraft gasifiers or a more conventional boiler design.
No they are not gasifiers. Air is blown in from the back and flue gases go up and out the flu. They are very simple.
 
Y'know what's pretty wild? they have a map on their website that shows a bunch of installs. down to name, phone number and address and boiler model. I wonder if their customers know that their info is there? I'm not sure I'd want a record of some non-listed boiler that I had installed at my place......
 
Y'know what's pretty wild? they have a map on their website that shows a bunch of installs. down to name, phone number and address and boiler model. I wonder if their customers know that their info is there? I'm not sure I'd want a record of some non-listed boiler that I had installed at my place......

When I talked to MBtek on the phone they claim the customers voluntary submitted their information to help other clients... not sure if many of them would answer never tried.
 
Not many reviews was looking into them few months ago.
 
As a customer, I can attest, they don't ask first. They put it up there immediately after I placed my order (would be months before I received the product) and then when I mentioned I was getting calls they told me they would be happy to remove it.
 
A year later and pretty happy with my UNI 35 boiler. MBtek has been a headache, for sure, but I don't find them to unscrupulous . I think it's a combination of being an overwhelmed startup company to a French Canadian/American culture adjustment that can infuriate one.
But good price for getting a wood fired boiler up and running with thermal storage etc. I would kill to have a true gasifier side by side to mine to see how much better they actually are from a practical point of view. I don't doubt they are more efficient, but curious from a big picture point of view if they're worth it.
 
Hey Oscar1111! I was the one who posted the original inquiry about the TIS boilers because I was interested in learning more about them. I actually contacted a few of the customers and got replies. Two customers in particular were incredibly helpful and we communicated all of last winter.
I kept going back & forth about whether to spend the outrageous amount for a high-end gasifiers...but I just can’t justify that kind of money when I still have to cut, split, stack, and stoke wood- even if it is less than other boilers! So, I’m almost ready to take the plunge...just deciding on the size now...it will be either a UNI55, 75 or 95. Going to call MBTEK today...been avoiding that because I’ve heard crappy stuff about the customer service ( but yet they have 100% star rating on eBay from thousands of customers...which isn’t easy to do!!)
I DON’T have patience for poor customer service. (Think I’ll tell the owner that right off the bat so they know I won’t tolerate any BS!).
I have a few questions I’m hoping you can help with. What exactly is involved with cleaning and how often did you do?
Do you have any water storage?
What is your heating system- forced air through an air handler? Infloor hydronic? Rads? Do you heat your domestic hot water with it too? Any problems with its opeartion (any breakdowns?) A big issue for me is smoke - both inside and outside. How did you find it? Looking forward to your feedback! Thanks! Patti
 
Any other owner input? The Uni 15 looks like it would be a sweet little heater for a greenhouse or shop that doesn't need insurance. At least if there is no visible smoke when charging storage. I certainly would not mess around with trying to modulate this kind of boiler.
 
Any other owner input? The Uni 15 looks like it would be a sweet little heater for a greenhouse or shop that doesn't need insurance. At least if there is no visible smoke when charging storage. I certainly would not mess around with trying to modulate this kind of boiler.

I was going to check with my insurance company sometime soon. Next year we are building an 80ft by 50ft in floor heat shop. It would be nice to burn cord wood and have pellets for backup. The Pellet Duo 60- 200k btu holds 880lbs of pellets!

But obviously without insurance it's not worth it unless putting up a small out building but defeats the purpose.
 
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I was going to check with my insurance company sometime soon. Next year we are building an 80ft by 50ft in floor heat shop. It would be nice to burn cord wood and have pellets for backup. The Pellet Duo 60- 200k btu holds 880lbs of pellets!

But obviously without insurance it's not worth it unless putting up a small out building but defeats the purpose.
I doubt any mainstream insurance company will write a policy for it.
 
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I started looking at the duo units, I really like the 35 wood/coal/biomass unit. Having a PTO chipper shredder makes a modulating chip boiler seem pretty enticing. No storage needed and I can burn wood pellets if I don't feel like dealing with chips. Would definitely want storage for burning cord wood.
 
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I started looking at the duo units, I really like the 35 wood/coal/biomass unit. Having a PTO chipper shredder makes a modulating chip boiler seem pretty enticing. No storage needed and I can burn wood pellets if I don't feel like dealing with chips. Would definitely want storage for burning cord wood.
How much do the PTO chippers cost? That's an interesting idea. Hydro company here gives away semi loads of wood chips for free. But would be nice to have a backup supply and help clean up waste from knocking down trees with own chipper.

Would probably need to screen the chips before loading aswell.
 
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I've been trying to find more info on these UNI wood boilers as well. Can anyone post some pics of the burn chamber? Does the manufacturers claim of +83% seem accurate? How does the quality compare to an Eko or similar entry level gasifier?
 
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How much do the PTO chippers cost? That's an interesting idea. Hydro company here gives away semi loads of wood chips for free. But would be nice to have a backup supply and help clean up waste from knocking down trees with own chipper.

Would probably need to screen the chips before loading aswell.
I have a "semi pro" grade Wallenstein BXM42. If you don't need/want a shredder you could get a decent imported machine for a few grand if you have 40+ pto HP. I have many uses for shredded and chipped wood, so it was worth it for me to pay a bit more for a machine that can do both.

I would assume any chip burner would need screened and at least partially dried chips. The Mbtek duo unit looks like it is fairly robust and could burn anything with the rotary pot with induction fan. The 35/160kbtu duo unit could even hold a decent sized load of wood for batch burns or set up with the chip hopper for times away from home.
 
I've been trying to find more info on these UNI wood boilers as well. Can anyone post some pics of the burn chamber? Does the manufacturers claim of +83% seem accurate? How does the quality compare to an Eko or similar entry level gasifier?

No, that claim does not seem accurate.
 
No, that claim does not seem accurate.
It may be possible. Many non-gasser wood stoves are rated for that, albeit they are not boilers. I talked to a Mbtek rep and asked him about test results. He referred me to their client map....he never did give any numbers, just said that 'highest efficency is when burning to storage' or some such.
The price is tempting tho....
 
Perhaps when these units are run at max output and then loading thermal storage they might be fairly efficient, but even then it's questionable. Owner photos and videos of the real units in use burning cord wood would be helpful as well.
 
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It may be possible. Many non-gasser wood stoves are rated for that, albeit they are not boilers. I talked to a Mbtek rep and asked him about test results. He referred me to their client map....he never did give any numbers, just said that 'highest efficency is when burning to storage' or some such.
The price is tempting tho....

I'm still saying not possible.

That is in the area of top of the line gassers. Which these most certainly aren't.

The fact your test result question was sidestepped is clear indication. Bogus numbers.
 
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I found a diagram and pictures of the heat exchangers. The thermal surface to extract heat seems to be adequate, I guess it comes down to how clean they burn?

Curious without secondary combustion if there is much smoke and creosote produced.
 

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I'm still saying not possible.

That is in the area of top of the line gassers. Which these most certainly aren't.

The fact your test result question was sidestepped is clear indication. Bogus numbers.

I decided to email Mbtek on that question. Sent the email at 514 pm. Had a reply at 538. After hours!! Ive attached the pdf test results they sent. Note: the results are for the Uni 35 because I told them I was interested in that one. Hopefully someone on here can tell me/us what kind of testing this was. If these results are reliable, I'm ordering one!

I also asked if the 35 could be hooked to a 6 inch chimney. They said as long as it's 15 to 20 feet. My new chimney will be 16 to 18, and I've already got some of the 6 inch.

I'm impatiently waiting to hear what the pros on here think of the results.
 
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That's an interesting test document. Seems legit, but then I feel skeptical about the fact that the efficiency is the same from 100- 30% output with cordwood. The unit is designed for pellets, as noted, but then the test procedure says it was hand loaded with birch.
 
So for cordwood the UNi actually does have secondary combustion. Both the Eko coal and pellet Duo don't have secondary combustion due to not being primary fuel use. Each model is designed to run optimal on specified fuel is what they told me.
 

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TL/DR: I don't mind lower efficiency if the emissions are like an EPA stove.

I also wish the emissions were rated in terms of g/hr like the EPA uses. So far I haven't found any kind of conversion or means to compare mg/m3 vs g/hr. Likely these units are somewhere between a traditional OWB and a modern indoor gassifier. I bet when used with wood pellets, or coal, the units are quite efficient, maybe even the claimed 89%. With cordwood I bet the efficiency is much lower, but maybe the duo units could come close. With the smaller firebox with a grate relatively close to the secondary combustion area the duo unit might be more like an EPA wood stove. My Serbian wood cookstove with adjustable air wash and bottom fed air, the secondary baffle is always open, burns very clean and gassifies quickly even with a water coil full of cold water. I'm willing to bet I'm losing efficiency with the glass top as well, but the Plume is very clean.