Uni tsi boilers opinions

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Here is the heat exchangers when only burning pellets. Slight difference in fly ash color.
 

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Looks like a decently clean burn with wood, and definitely a clean burn with pellets.
 
It has some pretty neat features I can get into next time I stop in at dad's place.

Off the top of my head it uses an outdoor temperature sensor to create a heating curve. We added on the touchscreen thermostat and wifi hub to remotely control and view parameters.

Also used the boiler radiant station for infloor heat with electric mixing valve which works pretty good. Few features still need to figure out.
 

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I would agree with earlier comments, not all water jacketed boilers are the same, there are some models that you see in the pictures that are horrible others aren't too bad and people don't know they are running. So you notice the bad ones.
Another factor in all this is that back in the old days some dealers didn't bother teaching the end user any useful loading techniques that help efficiency and reduce smoke. I have been amazed how much of a difference that makes.
All that ramble to say there is a big difference between talking in general terms of different designs v. specifics of performance and features on a particular unit. That's where the forum comes in. :)
 
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I would agree with earlier comments, not all water jacketed boilers are the same, there are some models that you see in the pictures that are horrible others aren't too bad and people don't know they are running. So you notice the bad ones.
Another factor in all this is that back in the old days some dealers didn't bother teaching the end user any useful loading techniques that help efficiency and reduce smoke. I have been amazed how much of a difference that makes.
All that ramble to say there is a big difference between talking in general terms of different designs v. specifics of performance and features on a particular unit. That's where the forum comes in. :)
Indeed, that's why I'm hoping someone will buy a wood only TSI UNI boiler ;lol
 
There’s a place on the town line with an old school smoker.
If he was my neighbor I’d perform a 30 round mag dump with green tips on it.
 
Those are the ones that turn people against wood burners.
 
Those are the ones that turn people against wood burners.
On my way to work there is a insulating contractor that heats their large steel/pole shed type building with one of the bigger conventional Central boiler OWB and I've seen it fog out four lanes of divided highway if the wind is in the right direction. Most of the time it's not too bad though. Lucky for them there is mainly other businesses around them but I bet there are complaints from time to time.
 
So are these UNI boilers worth using or too smokey?
This forum has yet to hear from an owner who has a wood only Uni boiler. Innocent until proven guilty is my verdict. The exhaust will certainly not be as clean as a Froling, Varm, etc. But clouds of smoke obscuring the neighbors and four lanes of traffic? No. Not with dry wood, a buffer tank and an owner with some common sense.
 
So are these UNI boilers worth using or too smokey?

That's a hard question to balance. Could be a reason other than smoke that might make it not worth using. And 'worth it' is kind of up to the buyer and their personal preferences and tolerances.
 
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The smallest model would have to be cute. It only takes a 14" log. It requires a 4" chimney. As in pellet stove pipe?
The UNI 500 on the other hand is a monster! 7,800 lbs, holds 515 gallons water, requires a 12" chimney, and accepts logs up to 90"! Gasp! One fire would heat my house for weeks!
 
Indeed, that's why I'm hoping someone will buy a wood only TSI UNI boiler ;lol

If the UNI burns wood as well as the pellet model I'd be optimistic.
 
After I build the heated barn perhaps I will get one.
 
If the UNI burns wood as well as the pellet model I'd be optimistic.

Pellet boilers have a few serious advantages over wood boilers when it comes to combustion, the evidence shows up on the EPA list. To start with the moisture content of wood pellets is usually 6-10% as opposed to wood in 20-30% M.C. range. Pellet burners only burn a small quantity of fuel at a time, not 50 lbs., so the fire is rarely overwhelmed or choked for air. Third advantage, they are self-feeding and self-igniting, when there is no call for heat the feed shuts down and the small quantity of fuel left in the fire box is consumed quickly and cleanly. Using propane or electricity to reignite makes the restart clean as well.
 
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So perusing the latest EPA qualified list, we are left with a handful of N.A. manufacturers that can qualify wood boilers that pass the latest emissions standards. Assuming Central Boiler bought up WoodMaster literally less than 5 N.A. manufacturers have demonstrated they can pass or afford the current standard of EPA testing. What the hell are they trying to accomplish? Most wood boiler makers employ less than 25 people, once gone, they're never coming back.
 
The step 2 epa levels have clobbered wood boiler manufacturers.
Most are gone now or bought out in Woodmaster's case.
Some of it could be their own fault in not getting ready, but you have to remember these are mostly small guys who can't realistically do a lot of expensive testing.
I get calls regularly for service on brands that are out of business. I can barely keep up.
 
Pellet boilers have a few serious advantages over wood boilers when it comes to combustion, the evidence shows up on the EPA list. To start with the moisture content of wood pellets is usually 6-10% as opposed to wood in 20-30% M.C. range. Pellet burners only burn a small quantity of fuel at a time, not 50 lbs., so the fire is rarely overwhelmed or choked for air. Third advantage, they are self-feeding and self-igniting, when there is no call for heat the feed shuts down and the small quantity of fuel left in the fire box is consumed quickly and cleanly. Using propane or electricity to reignite makes the restart clean as well.

Pellet boilers/stoves really should be in a different list than cordwood boilers. It's completely different like you described. It's a manufactured fuel.
 
I went to belkomin and they have a video of how they are built all heavy duty partial automated welded and thick steel. They look built really well. Its -50 in siberia, I cant see being that dangerous to have?
 
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Pellet boilers have a few serious advantages over wood boilers when it comes to combustion, the evidence shows up on the EPA list. To start with the moisture content of wood pellets is usually 6-10% as opposed to wood in 20-30% M.C. range. Pellet burners only burn a small quantity of fuel at a time, not 50 lbs., so the fire is rarely overwhelmed or choked for air. Third advantage, they are self-feeding and self-igniting, when there is no call for heat the feed shuts down and the small quantity of fuel left in the fire box is consumed quickly and cleanly. Using propane or electricity to reignite makes the restart clean as well.

That's true but we are talking about using storage...

Also as a test I burnt wood in the manual feed door on the pellet duo and still had good success. It can only get more efficient using the UNI.
 
The step 2 epa levels have clobbered wood boiler manufacturers.
Most are gone now or bought out in Woodmaster's case.
Some of it could be their own fault in not getting ready, but you have to remember these are mostly small guys who can't realistically do a lot of expensive testing.
I get calls regularly for service on brands that are out of business. I can barely keep up.
They had plenty of warning, but it seems none of them wanted to develop gasification technology, which has been commonplace on woodstoves, and the UMaine Jetstream boiler, since the 70's. European and a few select US manufacturers have been making gasification boilers for years now, so there were even plenty of proven designs to draw inspiration from.
 
European and a few select US manufacturers have been making gasification boilers for years now, so there were even plenty of proven designs to draw inspiration from.
Same with the forced air furnace MFG's...seems like most of them didn't even try until 2017...now, they gone
 
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How come you aren't trying to utilize the 26% tax incentives?

Plenty of options in the downdraft area...
 
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So perusing the latest EPA qualified list, we are left with a handful of N.A. manufacturers that can qualify wood boilers that pass the latest emissions standards. Assuming Central Boiler bought up WoodMaster literally less than 5 N.A. manufacturers have demonstrated they can pass or afford the current standard of EPA testing. What the hell are they trying to accomplish? Most wood boiler makers employ less than 25 people, once gone, they're never coming back.
I have heard that covid has stopped a lot of testing
The boilers can cross boarders for testing but the people who build run them can't without isolating ect.
Bringing the costs way up to get a proper test done.