Uni tsi boilers opinions

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Bingo!
Personally, if I were going to install a wood fired boiler without storage, there is 0.000000000000000000000% percent chance that I would get one without lambda control.
With lambda, I might consider going without storage...maybe...
I'm not so sure. With storage there is a huge piece of mind knowing it's not smoldering making a mess out of things but that's me.
 
Have you spoken with the owner of the MBTek? Make sure to ask if these boilers have the CSA/UL certification, if not your fire insurance will be void if your shop burns down. Do you know where they are made? They should be upfront with this info, could be Russia, possibly China, or some other 3rd world hell-hole, but certainly not made anywhere near Chester PA. where they are being stocked.

Anyone recognize the language on this 4th brochure on the right? That might be a clue...

 
Have you spoken with the owner of the MBTek? Make sure to ask if these boilers have the CSA/UL certification, if not your fire insurance will be void if your shop burns down.

Quite sure there was another thread on here that ended up revealing there was no certification. That alone would be a hard no here.
 
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No i have not spoke with them, just a few customers who say they work well.

To give a little insight they do work good. The Pellet Duo 40 is what my dad ended up putting in an out building. It's efficient, quiet and does as advertised. I was surprised at how well designed it is and all the options make it pretty slick (wifi thermostat controller, outdoor weather sensor, and boiler station.)

On the downside customer service is brutal and not sure how the guy can operate in that way and still have a business... completely disorganized, had to wait 2 months for the boiler to arrive when he said would only be 1 month. Then found out it was only half the shipment and all the additional add-ons came a week after that putting a monkey wrench in the installation.

Only buy one if you have an outbuilding/wood shed that is away from primary buildings. In my opinion it's worth it to have everything separate anyway because keeps the mess in a separate building, good piece of mind, and even if it was CSA approved it would still increase your insurance rate.

Now for any US residents that can utilize the 26% tax credit it would be a no-brainer to go with an approved certified unit.
 
The same scam pop up every couple of years, swear the last time it was out of Quebec.....maybe it's even the same guy. Somebody imports a container full of cheap wood boilers made in the 3rd world and blows them out at half the price of any other product on the market. Once they're gone the business probably will be too before any govt. body catches up. Buyer beware, good luck finding parts for a boiler made in Belarus.
 
The same scam pop up every couple of years, swear the last time it was out of Quebec.....maybe it's even the same guy. Somebody imports a container full of cheap wood boilers made in the 3rd world and blows them out at half the price of any other product on the market. Once they're gone the business probably will be too before any govt. body catches up. Buyer beware, good luck finding parts for a boiler made in Belarus.

Customer support is crap... but they have been around for about 6 years or more.

This has been a topic quite few times on this forum... kinda like who is going to bite the bullet first lol.
 
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Customer support is crap... but they have been around for about 6 years or more.

This has been a topic quite few times on this forum... kinda like who is going to bite the bullet first lol.

I hope a forum member takes the plunge. I'm dying to know if the wood only version is worth a crap. I know it's not a downdraft boiler, but it should be at least 75% efficient even as an updraft boiler.
 
I hope a forum member takes the plunge. I'm dying to know if the wood only version is worth a crap. I know it's not a downdraft boiler, but it should be at least 75% efficient even as an updraft boiler.

Highly highly doubtful on 75%. I am guessing my gasser might be 80% under it's best conditions. Lambda boilers are more. After living with it for 8 years now, and comparing to my prior water jacketed slug the 17 years before that, I would ballpark the slug at 40%. At very best.
 
Highly highly doubtful on 75%. I am guessing my gasser might be 80% under it's best conditions. Lambda boilers are more. After living with it for 8 years now, and comparing to my prior water jacketed slug the 17 years before that, I would ballpark the slug at 40%. At very best.
Why do you doubt 75%? There are freestanding woodstoves in that territory, so to me it doesn't seem like a jump when you have thermal storage.
 
Stoves and boilers are apples and oranges. First hit on efficiency would be lack of gasification/secondary burn. Pretty sure this is still a liquid cooled firebox appliance. Second would or might be heat exchanging. After all the things I have read on these, it's still not clear if they have tubes or not. Doesnt look like it on the cut away view in their 'manual'. Someone did say they thought they saw a picture showing tubes, but I haven't seen it. Then there is the catch-22 that even if they have tubes, the dirty burn will likely dirty them up in a hurry. Would need fairly constant attention to maintain optimum transfer efficiency. Adding storage and batch burning would no doubt help, but I wouldn't expect much more than something like 60% efficiency. Too bad we didnt have some real world info, but there doesn't seem to be any even after all this time.
 
The cutaway looks like a regular old style updraft grated boiler, with no secondary burn. I can't see how it could pass EPA, but maybe no one cares.
Not saying it's a bad unit, but there's scant info and shouldn't be compared to a true gasser.
 
Why can't secondary combustion happen? Is it because the stove has a water jacket? My cookstove with a bottom grate and secondary air inlets burns all the smoke, but it also has a refractory lined firebox and just a water coil, not a water jacket.
 
Why can't secondary combustion happen? Is it because the stove has a water jacket? My cookstove with a bottom grate and secondary air inlets burns all the smoke, but it also has a refractory lined firebox and just a water coil, not a water jacket.

Yup that's the primary reason. Gasifying boilers do their secondary burning in a refractory lined secondary burn chamber.
 
Not totally sure but I believe all woodstoves that achieve true secondary combustion do so through the magic of a catalytic converter, which is a consumable.
 
Not totally sure but I believe all woodstoves that achieve true secondary combustion do so through the magic of a catalytic converter, which is a consumable.
I have two stoves that do not use catalysts and I believe both are 75% efficient.
 
A water jacketed boiler has a very difficult time consistently burning off gasses unless it downdrafts through the hot coals and into a seperate reburn area.
An updraft design that burns up against the water jacket is too cool except late in the burn.
My experience tinkering around anyway.
 
That pretty much kills any chance I would take a risk on one of these boilers. I could forgive the low efficiency, but smoky exhaust is a deal breaker.
 
I could forgive the low efficiency, but smoky exhaust is a deal breaker.
They don't call old school OWB's "smoke dragons" for no reason! Worst of the worst! They make an old school stoves look like something out of the future...not kidding!
This is probably right after a call for heat, but still, it gives you the idea! (they do clean up some after the fire builds)
The second pic would probably be more typical of "idling"...which happens most of the day/night.
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They don't call old school OWB's "smoke dragons" for no reason! Worst of the worst! They make an old school stoves look like something out of the future...not kidding!
This is probably right after a call for heat, but still, it gives you the idea! (they do clean up some after the fire builds)
The second pic would probably be more typical of "idling"...which happens most of the day/night.
View attachment 275684 View attachment 275685
That's atrocious
 
That's atrocious
Agreed...and I think anyone on here that has one in the neighborhood will admit that my pics are pretty typical of an old school OWB, especially if they don't run burn truly dry wood (and most don't)
My dad has a 20 year old Central Boiler and it makes clouds like that, and worse sometimes, fortunately I have convinced them to run dry(er) wood, and that has helped...there have been times in the past that the smoke cloud from the boiler was blowing across the road and the smoke was so thick people were actually slowing down to drive through it! !!!
I finally have them convinced to buy a gassifier to replace the 20 YO CB...looking at HeatMasters currently...
 
Agreed...and I think anyone on here that has one in the neighborhood will admit that my pics are pretty typical of an old school OWB, especially if they don't run burn truly dry wood (and most don't)
My dad has a 20 year old Central Boiler and it makes clouds like that, and worse sometimes, fortunately I have convinced them to run dry(er) wood, and that has helped...there have been times in the past that the smoke cloud from the boiler was blowing across the road and the smoke was so thick people were actually slowing down to drive through it! !!!
I finally have them convinced to buy a gassifier to replace the 20 YO CB...looking at HeatMasters currently...
I would hope these UNI TSI boilers would be better than an older OWB smoke dragon, especially when batch burning to charge storage, but seems that the odds are against that. After living with modern EPA stoves I would never go back to a smoke dragon.
 
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I would hope these UNI TSI boilers would be better than an older OWB smoke dragon, especially when batch burning to charge storage,
Even old school models do better when batch burning...
 
I would hope these UNI TSI boilers would be better than an older OWB smoke dragon, especially when batch burning to charge storage, but seems that the odds are against that. After living with modern EPA stoves I would never go back to a smoke dragon.

They aren't bad as people make them out to be. The pictures attached show batch burning with no secondary air... being that it is a pellet model it does not have the secondary and not optimized for burning cord wood. No visible smoke outside....

But as @brenndatomu mentioned above smoke is mainly a problem when going into a burn cycle or when heat is satisfied.

From what I understand the UNI does do a pretty good job... better than a smoke dragon but I agree that storage might be a must when using water cooled firebox with no brick lining.

We primarily burn pellets and it burns very clean. Exhaust doesn't smell at all. Nice to have the option if something breaks to switch to manual burn.
 

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