Froling wood boiler installation underway!!

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So tonight I am getting ready to post some pictures of the heat exchanger cleaning that I did on the Froling tonight... in the meantime, here is a decent shot of the gasification torch on the Froling. It's actually kind of amazing that I was able to get such a good shot through that tiny little glass peep-hole in the bottom door. You will notice that the torch comes out of the upper chamber tangential to the circular refractory, creating a swirling of the gasses. This effectively increases the residence time of the wood gas in the high temperature environment of the refractory, as well as helping to pulverize the solid particles of ash and coal.

If nothing else, we all love a good shot of some gasification. Enjoy... and stay tuned for some heat exchanger shots.

cheers
 

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So, as promised, here are a few shots of the heat exchanger cleaning process. The first two photo's are of the exterior panel that allows access to the removable hatch that covers the top of the heat exchanger. You will notice that there are no screws to remove. Simply lift the panel out of the recessed pocket that it sits in, and your on the inside.

The second two photo's are of the inner hatch. Two heavy anchor bolts tie the hatch to a couple of tabs on each side of the vessel at the top of the heat exchanger. The anchor bolts are tightened by the large black knobs on either side. This hatch comes complete with a gasket for a good seal and an insulating type refractory. As you can see... access to the heat exchanger for cleaning is just about as easy as it gets.

The third picture is of the hatch itself. Pretty self explanatory.

More to come...

cheers.
 

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These next shots are of the inside of the heat exchanger. At this point, the boiler has just over 100 hours of service on it, so I didn't really expect to see much inside in the way of crusty soot anyways... but aside from the fly ash, the tubes were completely free of any solid buildup whatsoever. I could have cleaned the tubes with a rag. The draft fan was also free of any buildup, except for a little dust.

In order to take apart the shaker assembly, the two bolts need to be loosened on the clamp that you see on the turbulator assembly. This clamp holds the turbulator assembly tight to the rod that it hangs on between the vessel sides. The rod, and the handle that you see on the exterior of the boiler, are all one piece. So basically, loosen 2 10mm bolts and you can pull the turbulators out, which you can also see are very clean, save a bit of dust.

Once everything is out, just run the brush that is supplied by Bioheat (among other tools that come with the boiler that I haven't had a chance to tell you about) through the tubes, then sweep out the ash and you're ready to put everything back together. It only took a few swipes of the bore brush to remove the built up dust, at which point the tubes looked brand new inside.

One more post on it's way to put everything back together...

cheers
 

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Putting the turbulators back into the tubes can be tricky by yourself when you have low ceilings. But hanging the turbs over the edge like in the first picture becomes your second set of hands while you attach them through the holes on the shaker assembly.

This whole process took maybe 15 minutes from start to finish. When it's easy to do a cleaning, it's easy to keep the boiler running at peak efficiency all season long... which should save you a little wood over the course of a winter. I can see myself giving the boiler a scrubbing probably every 4 to 6 weeks just for this reason.

My next project will be to get the real-time video of the lighting procedure posted on the website for everyone to see. Once the upper chamber is loaded, it's 3 minutes 30 seconds from start to finish, and you walk away from the boiler. I'm no movie director, but I think I can make the video look decent enough. I also took some video through the peep hole today so I can watch it on my laptop... never get tired of seeing the torch.

That's all for today. Hope you enjoyed the pics. Enjoy the weekend.

-cheers
 

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OK, this is my first attempt at Youtube videos... but I just embedded a video of the Froling's gasification torch onto our website. It's a little rough, and I'll eventually try to get some higher resolution video posted, but you still get the idea.

You will note about halfway through the video that the camera goes a little hay-wire... i had the middle lighting door open and then shut it half way through the video... sorry... I'm still an amateur, and will thus likely remain.

http://hillsideenergy.com/froling_turbo_3000.htm

I'll try to get a realtime video of lighting the boiler up soon.

cheers
 
Nice! I can see where that rotating flame would put a lot of the heat into that chamber & the 10 fire tubes would take out a bunch more. Even though I can't afford it now it sure is nice to see this boiler. You did very well with the video, Randy
 
Piker; What happened to the "hot plates" as I heard them refered to. My literature from about 1 1/2 years ago clearly shows about 6 vertical plates in the primary chamber & they are said to be 3mm thick.. Your install shows the dimpled walls & unless I missed it, no plates. Was Froling just trying to keep the cost down, design change? I know the Atmos for Germany(GSE) is far fancier, Randy / I ran through the thread again & it looks like they are probably there, it's hard to tell on the sides though.
 
Singed Eyebrows said:
Piker; What happened to the "hot plates" as I heard them refered to. My literature from about 1 1/2 years ago clearly shows about 6 vertical plates in the primary chamber & they are said to be 3mm thick.. Your install shows the dimpled walls & unless I missed it, no plates. Was Froling just trying to keep the cost down, design change? I know the Atmos for Germany(GSE) is far fancier, Randy / I ran through the thread again & it looks like they are probably there, it's hard to tell on the sides though.

Firebox aprons... 3mm thick... I posted a pic of the firebox back a couple pages, and you can kind of see them inside, but the picture isn't the best. They are on the sides and back of the firebox. It's amazing how little creosote you find in the upper chamber of this unit because of those. Actually none whatsoever on the aprons themselves... and my guess is not much behind them either because the aprons are still hanging loose inside. The dimples that you saw were on the outside of the vessel... called quilting... used in place of stay-bolts where possible.

Maybe i should take some better pictures of the aprons... installed and removed for say a seasonal cleaning.

cheers
 
Finally... realtime video of lighting the Froling. Please excuse the total lack of video skills... and narration skills... Do I really sound like that in real life?

At any rate, here's the link. It will be the video on the right once the page has loaded:
http://hillsideenergy.com/froling_turbo_3000.htm

On another note, I need to correct something I said in the last post. The firebox aprons are not just on the back and sides of the upper chamber... they are also on the front. I took one out and took a couple pictures to post tonight, but then inadvertently erased them to take the video of lighting the boiler. I'll get that posted up by the end of the week... it's clean inside, even behind the aprons. No runny creosote to be found in the upper chamber of the FHG.

that's all for tonight... enjoy the video, such as it is.

cheers
 
Piker - great write up and perfectly useable videos.

I am not as familiar with the DD gassers, but perhaps that tangential nozzle flame will help prolong the life of the refractory materials. Direct impingement will certainly cause a higher scouring rate than angular impingement. Good engineering.

How many nozzles are there in the FHG? With my GARN there is only a single gassification flame, but it's as big as my thigh!

For a single district system, an FHG with 1k or 1.5 gals of storage looks ideal.

Best of luck with your system.
 
Froiling has officially become my #1 choice if money were no issue. Froiling has nudged out Garn by a small margin on my wish list. I suspect there would be a noticable savings in wood consumption over most competitors as well...
 
Jim K in PA said:
Piker - great write up and perfectly useable videos.

I am not as familiar with the DD gassers, but perhaps that tangential nozzle flame will help prolong the life of the refractory materials. Direct impingement will certainly cause a higher scouring rate than angular impingement. Good engineering.

How many nozzles are there in the FHG? With my GARN there is only a single gassification flame, but it's as big as my thigh!

For a single district system, an FHG with 1k or 1.5 gals of storage looks ideal.

Best of luck with your system.

I am glad that folks are enjoying the thread. The whole process of installing this boiler, cataloging the install, and learning how to operate it has been tons of fun for me. I feel like a kid with a new toy, and I'm just thrilled with the results so far. This was a good move for us, no doubt about it. It has certainly made life easier on us with regards to operation of the heating system.

I hadn't given it much thought, but maybe you are right about the tangential nozzle extending the life of the refractory. I can't say that it will or will not - cause I simply don't know... but it makes sense. I believe Froling states a 10 year lifespan on the refractory. Cool thing about it is, the entire refractory mass can be replaced by simply sliding a new one in. No poured refractory mass to chisel apart and repour inside the vessel like our last unit. When it's time to replace the refractory, you break the circular refractory along the sides where it's thinnest, and work the pieces out as the entire unit is sort of mortised and tenoned to the vessel with metal tabs... then the new refractory just slides in. Once in place, you slide new metal tabs through some slots in the refractory into the vessel to hold it in place. I have never done it, but it sounds simple... maybe a 30 minute job? An hour tops? Who knows... I don't think I'll have to worry about it for a while.

The other thing i like about the refractory in this boiler is the top of the nozzle... it's not refractory... it's cast iron. Just a square piece of cast plate with a slot down through the center of it that sits over the nozzle atop the circular refractory mass. Instead of chiseling out a refractory nozzle brick every two or three years for replacement, you can just slip this piece of cast out and put a new one in if necessary. Not sure what the life expectancy of this cast nozzle-top is. I would think more than 3 years if you're not banging it around all the time. I'll take some pics of that next time i'm down there photographing and making terrible videos. :)

The Froling does what it does with one nozzle... I don't have measurements in front of me, but it looks to be a little bigger than the one our other boiler had. Not that a bigger nozzle implies anything... just noting the difference.

Thats all for now... have a pleasant evening.

cheers
 
sparke said:
Froiling has officially become my #1 choice if money were no issue. Froiling has nudged out Garn by a small margin on my wish list. I suspect there would be a noticable savings in wood consumption over most competitors as well...

According to the numbers I have run so far, I think I can conservatively guesstimate around a 20% reduction in fuel usage compared to our previous unit, just based on delivered btu's to our tanks now compared to before. That seems like a lot, I know, but I don't know how else to read the numbers. With Froling stack temps that stick near 300 for most of the burn, compared to 650° or more, the increase in heat exchange alone is significant. Couple that with a higher average combustion efficiency over the course of a burn due to the lambda technology, and output-load matching, and it kind of makes sense. Again, not throwing ANY of the other gasification units under the bus here... just noting differences from the only hands-on frame of reference that i have.

cheers
 
"I am glad that folks are enjoying the thread."

What's not to like about that Froling? grin.

Great job on the vids and the thread in general. Congrats on the boiler too. They are pretty neat.
 
Piker said:
Jim K in PA said:
Piker - great write up and perfectly useable videos.

I am not as familiar with the DD gassers, but perhaps that tangential nozzle flame will help prolong the life of the refractory materials. Direct impingement will certainly cause a higher scouring rate than angular impingement. Good engineering.

How many nozzles are there in the FHG? With my GARN there is only a single gassification flame, but it's as big as my thigh!

For a single district system, an FHG with 1k or 1.5 gals of storage looks ideal.

Best of luck with your system.

I am glad that folks are enjoying the thread. The whole process of installing this boiler, cataloging the install, and learning how to operate it has been tons of fun for me. I feel like a kid with a new toy, and I'm just thrilled with the results so far. This was a good move for us, no doubt about it. It has certainly made life easier on us with regards to operation of the heating system.

I hadn't given it much thought, but maybe you are right about the tangential nozzle extending the life of the refractory. I can't say that it will or will not - cause I simply don't know... but it makes sense. I believe Froling states a 10 year lifespan on the refractory. Cool thing about it is, the entire refractory mass can be replaced by simply sliding a new one in. No poured refractory mass to chisel apart and repour inside the vessel like our last unit. When it's time to replace the refractory, you break the circular refractory along the sides where it's thinnest, and work the pieces out as the entire unit is sort of mortised and tenoned to the vessel with metal tabs... then the new refractory just slides in. Once in place, you slide new metal tabs through some slots in the refractory into the vessel to hold it in place. I have never done it, but it sounds simple... maybe a 30 minute job? An hour tops? Who knows... I don't think I'll have to worry about it for a while.

The other thing i like about the refractory in this boiler is the top of the nozzle... it's not refractory... it's cast iron. Just a square piece of cast plate with a slot down through the center of it that sits over the nozzle atop the circular refractory mass. Instead of chiseling out a refractory nozzle brick every two or three years for replacement, you can just slip this piece of cast out and put a new one in if necessary. Not sure what the life expectancy of this cast nozzle-top is. I would think more than 3 years if you're not banging it around all the time. I'll take some pics of that next time i'm down there photographing and making terrible videos. :)

The Froling does what it does with one nozzle... I don't have measurements in front of me, but it looks to be a little bigger than the one our other boiler had. Not that a bigger nozzle implies anything... just noting the difference.

Thats all for now... have a pleasant evening.

cheers
Thats interesting Piker about the cast piece. I'm having excessive nozzle wear(just on the top) with my Atmos. I thought about putting a steel protection plate on top & gave this up because I though it would gassify too fast. I'm going to give it a go now. Thanks, Randy
 
I've had a few questions regarding the video that I linked to on lighting the Froling, most of which have to do with how the process happens so quickly. I think the easiest way to address this is just to show in a still photo what was not visible in the video... the residual coal bed. This photo shows the amount of coals that are commonly left over for the next firing once the froling has shut down. I moved some of the coals around over the nozzle to make it more visible. Remember that the control on the froling will not allow the storage circulator to stop until the bottom of the tanks are within a few degrees of the boiler, so producing steam inside the vessel from the coals is not an issue.

cheers
 

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... and the firebox aprons. I removed the right side - front apron for these shots. The apron itself has not been cleaned... just removed and photographed. Notice that niether the front nor the back of this apron has any creosote build-up. Behind the aprons, on the vessel walls, there is an extremely thin layer of black glossy creosote. This layer, at first glance, looks like paint. It is so thin that the aprons do not stick to it at all. Note the holes at the bottom of the apron where primary air is introduced at the bottom of the firebox.

cheers
 

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At last, a couple shots of the cast iron nozzle piece. This comes in two symmetrical pieces (right and left hand) and sits neatly inside of a formed pocket on top of the refractory. Shown is the left side piece.

cheers
 

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Very impressive and thanks for sharing-- I had a chance to behold a Froling in person earlier today at the BioHeat trailer at the Northeast Logging Expo-- a very well designed and made unit (though I've had nothing but satisfaction so far with my existing Econoburn). The Froling's unique small "starting door" at the bottom of the main firebox is a really great idea
 
Did you use a duravent stove adapter or did the elbow fit directly on the boiler. I'm switching from single wall to double wall and trying to figure out what I need to order.
 
Hi,

I'm new to this forum, I was missing out, lots of great info on this site.

Great post Piker, great breakdown on the install of the Froling.

I'm setting up my Froling 40/50 & would like to know a good size lenght needed (to be safe) of 3/4" High output baseboard for the dump/power out.

Richard
 
bro-tek said:
Hi,

I'm new to this forum, I was missing out, lots of great info on this site.

Great post Piker, great breakdown on the install of the Froling.

I'm setting up my Froling 40/50 & would like to know a good size lenght needed (to be safe) of 3/4" High output baseboard for the dump/power out.

Richard

First of all... Congrats on the new boiler!! I am sure that everyone here would enjoy pics and discussion about your installation, so please feel free to share!

Tarm Recommends 10% of the rated output for a gravity loop... going by the 40kw rating, I would think that 20' should do it. We're using 24' of regular old fintube here and have never had a problem.

cheers
 
Tks piker, will post pics once i get the heat is on.... A couple weeks I hope....
 
Have a Froling 30 that's been going for a few weeks, and one problem we've encountered is that the secondary combustion doesn't seem to be taking place effectively. During a burn, the secondary air damper usually doesn't open past the programmed minimum (10%) due to excessive residual O2.

The wood is mostly red oak seasoned a year. Most of it got snowed on this winter, but I didn't expect that to make too much of a difference with the burn. I saw similar problems when using kiln dried hardwood as well. That was unexpected. When I put the seasoned wood and the kiln dried variety in my Jotul 602 they go pretty well.

In the programming settings, I tried adjusting some of the air parameters to deal with another issue - heavy condensation in an exterior chimney with a clay liner. The default minimum stack temp is 120C. I bumped it up to 150C to prevent the worst of the moisture issues. That seemed to help.

This morning's burn, as well as this evening's, have both been disappointing. I need to run with the lighting door open for at least 30 minutes to get the flue gas up to temp. If I shut it before the stack temp reaches 175C, the stack temp falls so fast that the boiler goes into shutdown status. Residual O2 stays between 14-18% for the vast majority of all the burns. I would think that this meant I wasn't generating enough heat in the primary combustion chamber to produce enough gas for secondary combustion.

Our installer recommended checking the butterfly valves for the air intakes on the left and right sides of the boiler. They are both in the same position, so it looks like they were installed correctly.

I'm going to increase the max ID fan speed to 95%. That seems to get the primary chamber up to a higher temp and give a better chance of gasification, but I know that it also skews the ratio of primary to secondary air and could make the system less efficient.

Willing to hear any suggestions folks have. Someone recommended I try biobricks, which I'm willing to use as a control to make sure the boiler is operating correctly. I'd like to make it work with cordwood, though. From the literature I read, the Turbo 3000 could operate with wood at a higher MC, even up to 30-35%, albeit at decreased efficiencies, with the sweet spot falling around 20% MC.

Thanks!

Jesse
 
jbastide said:
Have a Froling 30 that's been going for a few weeks, and one problem we've encountered is that the secondary combustion doesn't seem to be taking place effectively. During a burn, the secondary air damper usually doesn't open past the programmed minimum (10%) due to excessive residual O2.

The wood is mostly red oak seasoned a year. Most of it got snowed on this winter, but I didn't expect that to make too much of a difference with the burn. I saw similar problems when using kiln dried hardwood as well. That was unexpected. When I put the seasoned wood and the kiln dried variety in my Jotul 602 they go pretty well.

In the programming settings, I tried adjusting some of the air parameters to deal with another issue - heavy condensation in an exterior chimney with a clay liner. The default minimum stack temp is 120C. I bumped it up to 150C to prevent the worst of the moisture issues. That seemed to help.

This morning's burn, as well as this evening's, have both been disappointing. I need to run with the lighting door open for at least 30 minutes to get the flue gas up to temp. If I shut it before the stack temp reaches 175C, the stack temp falls so fast that the boiler goes into shutdown status. Residual O2 stays between 14-18% for the vast majority of all the burns. I would think that this meant I wasn't generating enough heat in the primary combustion chamber to produce enough gas for secondary combustion.

Our installer recommended checking the butterfly valves for the air intakes on the left and right sides of the boiler. They are both in the same position, so it looks like they were installed correctly.

I'm going to increase the max ID fan speed to 95%. That seems to get the primary chamber up to a higher temp and give a better chance of gasification, but I know that it also skews the ratio of primary to secondary air and could make the system less efficient.

Willing to hear any suggestions folks have. Someone recommended I try biobricks, which I'm willing to use as a control to make sure the boiler is operating correctly. I'd like to make it work with cordwood, though. From the literature I read, the Turbo 3000 could operate with wood at a higher MC, even up to 30-35%, albeit at decreased efficiencies, with the sweet spot falling around 20% MC.

Thanks!

Jesse

There's something definitely wrong if it's taking 30 minutes to get the flu gas up to temperature. I will generally see 100° C within 3 minutes of starting a fire. Peak stack temps are generally not more than 200° C. The only thing I have ever seen cause slow startups is green wood, which you seem certain is not the case here... I would still like to see a moisture meter reading though.

The drier fuel, ie kiln dried, will produce fantastic amounts of woodgas in a short period of time. The froling will compensate by closing the primary air more, and opening the secondary air. With biobricks, (5% moisture) I have seen 10% primary air settings with 90% secondary air... and a fantastic secondary flame.

30 to 35% moisture is way too high for any wood burning device to be effective. 20% or less is key to great gasification... 15% is even better... basically, the lower the moisture content the better.

I can definitely see where condensation could be an issue with a tile chimney, especially if the chimney is outside the home and the wood is green.

I don't think that changing the max fan speed should be necessary... though it shouldn't skew the primary/secondary air ratio like you say. The dampers control this ratio regardless of fan speed.

Your O2 levels will be high while you leave the lighting door open. Your secondary damper will not start to meter the secondary combustion air until you close the outer door. The fact that you can't get a good fire in the upper chamber, and your O2 readings seem out of whack... leads me to think there is an issue with the dampers not being timed properly. I would start there...

cheers
 
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