Pellet Burner Conversion

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I'm really interested in doing a conversion too. My heating system right now is 2 boilers. The primary is a Harman VF3000 which burns rice coal. The backup is a System 2000 oil boiler. The boilers are hooked up in parallel (not in a series), so when the coal boiler is hot, the oil boiler remains at room temp. Only if the coil boiler malfunctions (i.e. I forget to add coal), does the oil boiler turn on. Zone valves prevent the hot water from the operating boiler fgrrom going through the other boiler.

I want to convert my Harman from coal to pellets. The coal works great and is pretty cheap (just over $200/ton delivered), but it is EXTREMELY dirty. During the coldest part of the winter I have to empty about 80 lbs of cinders out of it and fill the hopper with another 250 lbs of coal. Both processes create a tremendous amount of dirt and dust. I probably should wear a dust mask because after I do it I have a lot of coal dust in my nose.

I would really like to hear the results of the conversions. How difficult was it to put the pellet burner in, how often do you have to clean it and have you had any problems with it. The Pellx really sounds interesting with the self-clean (hook it up to an air compressor).

I tried contacting Harman to see if I could buy a pellet burner from them and got absolutely ZERO help. Just a "we don't offer a kit to do that".

Thanks!
Steve
 
Steve, it sounds like you might have a good possibility for conversion. You need to be able to mount the burner that is much like an oil burner, but bigger around (6"), on to a flat surface of the Harman VF3000. I looked up your boiler and it looks like an oil burner is an option so this might be the perfect spot for this conversion. When I cut the hole in my boiler I had 2 steel plates made with identical holes for bolts so I am able to go back and forth with either the PELLX or the oil burner. The PELLX requires a well for a temperature probe but I was able to use that same well as my Aquastat and you will also need this as a safety shut off.

I heat both my hot water and heat my house with the one unit. I built a bin that holds 2000# of pellets so I don’t need to fill it very often. During the coldest part of this last winter I would burn 1000# per week. I would need to clean my burner every 1000#, a 15 minute job, and clean my boiler every 2000#. I use a central vacuum that vents outside, and that keeps most of the dust down. After burning the 2000# I end up with a 4 gallon bucket of ashes that doesn’t weight anything.

My goal was to same money compared to Oil, set the thermostat at a constant level, heat my hot water all year without the use of oil and spend as little time with the unit as possible. The PELLX with its self start and shut down has been my answer. The self cleaning is good to a point but you will still need to clean it every 1000# or so.

I can’t say enough about the PELLX as I used to burn coal in the winter with oil the rest of the year. I will say that it was cheaper to heat with coal than pellets. In the long run I will be making pellets and cut the cost down to almost nothing.

Good luck and if you decide to convert let me know and I can save you about 10% on the cost of the burner, auger and control box.
 
Hoval said:
Steve, it sounds like you might have a good possibility for conversion. You need to be able to mount the burner that is much like an oil burner, but bigger around (6"), on to a flat surface of the Harman VF3000. I looked up your boiler and it looks like an oil burner is an option so this might be the perfect spot for this conversion. When I cut the hole in my boiler I had 2 steel plates made with identical holes for bolts so I am able to go back and forth with either the PELLX or the oil burner. The PELLX requires a well for a temperature probe but I was able to use that same well as my Aquastat and you will also need this as a safety shut off.

I heat both my hot water and heat my house with the one unit. I built a bin that holds 2000# of pellets so I don’t need to fill it very often. During the coldest part of this last winter I would burn 1000# per week. I would need to clean my burner every 1000#, a 15 minute job, and clean my boiler every 2000#. I use a central vacuum that vents outside, and that keeps most of the dust down. After burning the 2000# I end up with a 4 gallon bucket of ashes that doesn’t weight anything.

My goal was to same money compared to Oil, set the thermostat at a constant level, heat my hot water all year without the use of oil and spend as little time with the unit as possible. The PELLX with its self start and shut down has been my answer. The self cleaning is good to a point but you will still need to clean it every 1000# or so.

I can’t say enough about the PELLX as I used to burn coal in the winter with oil the rest of the year. I will say that it was cheaper to heat with coal than pellets. In the long run I will be making pellets and cut the cost down to almost nothing.

Good luck and if you decide to convert let me know and I can save you about 10% on the cost of the burner, auger and control box.

I can easily unbolt the coal burner assembly. The hole that is left in the boiler is about 12 3/4" wide by 8 3/4" tall. There is only 2 bolts that hold the coal burner on here. I know a metal fabricator, so 1/4" boiler plate with a laser cut round hole in it won't be an issue at all.

I currently have 3 aquastats. The first controls the burner and the high-temp override. My high temp override turns on my boiler circulator (boilers in parallel) and it also turns on one of my heating zones (another circulator). The second aquastat controls the temp at which I want all zones to shut off. This is currently set at 150. I put this in so that if the fire is going and too much heat is being extracted (cooling the boiler), I give the coal time to 'catch up'. The third aquastat (set at 140) controls the power to the oil boiler. The only time this takes affect is when I run out of fuel.

I also heat my domestic hot water with both boilers using the System 2000 storage tank. Another circulator and 2 more zone valves. The domestic hot water either goes through the coal boiler OR it goes through the oil boiler (never both).

I can easily deal with having to clean it once a week. I look forward to being able to dump the ashes in my lawn instead of having to dump into a galvanized steel garbage can. Then, once they are COLD I can put them in bags and haul them out with the garbage (I produce more cinders in a week than I can leave for my garbage hauler, so it usually takes me well into the summer before all my cinders are gone).

I plan on converting my coal bin to a pellet bin. Then, I'll be able to dump the pellets from inside my garage without having to take them downstairs to the boiler. My coal bin is about 4' x 8' and 8' deep. It is right at the front of my garage below the garage floor.

I definitely am going to convert. It will be either Pellx or Ulma. I really want to see one in operation first. Is it possible to meet up with you? I can PM you my email address and I'll include my full-name, address and phone numbers in an email.
 
I have been running a Pellergy unit for three + years and love it. Check them out: www.pellergy.com; the one down side is that they only sell through their Certified Installers, but they will train any licensed home heating person, company or plumber. Good unit, built in the USA from a Swedish design and great support.
 
Geo. said:
Pellet burners alone can work fine on a wood boiler that you're not planning to use for heating wood anymore, but there are issues with using an oil boiler.

1. Burners should be on a door for cleaning. If not on door, removing the burner for cleaning wears out the seal.
2. There's no provision for ash in oil boilers.
3. Oil boilers are not designed for regular cleaning of the heat exchange surfaces, which is an important requirement for burning any kind of biomass, including wood pellets.
4. Combustion chambers are too small in oil boilers for efficient combustion.

It's also a good idea to leave an oil boiler in place as a back-up, in the event you're called away and not able to refill the bin. Large homes can use the oil boiler for supplemental heating for when heat losses are at their greatest.

Swebo burners haven't been mentioned in this thread. They are also Swedish technology, and run on high and low limits. A back-up oil boiler would have high and low limits below the high and low limits of the pellet boiler. This keeps the pellet boiler running as much as possible. Power levels can also be adjusted so that in spring and fall, the burner can run at lower power and so with longer run times which increases the efficiency. Adjustments can also be made to all four phases of combustion, and to fan speeds at every power level. As with all the Swedish burners, they are very well made.

I'm going to meet with this fellow next week...Gosh he's 14 miles away.
 
I started this thread and finally have had time to install the darn thing.
Funny how a year goes by that quickly.
From looking at the thread, looks like these are catching on a bit.

Well here are the facts (with the proof required):
I called Pelletpro to say that to ask a couple questions (Has been a year). Guy said that he would start the warranty from November of this year. thought that was kind of nice.
Decided to put it into my Biasi to make sure I am happy with it before I spend a bunch on a new boiler.

Here's the facts:
house - 3600'
6 baseboard zones
2 radiant zones
hot water maker running agaist 2 teenage girls, one wife, me.

Install time - 3 hours (easier than I thought by a long shot)
Install gas temp - 375
Outside temp. - 30 average
Usage - 22 bags in two weeks. (Wanted to check after 1 week, but my boiler tech buddy was gone so I couldn't get his analyzer)
Flue temp - 433 (Pelletpro said it should go up by about 100 degrees before cleaning.)
Ash - 1 1/2 gallons from Independence all softwood pellets (Pelletpro said to use as high a softwood content as possible.) No clinkers, no hard stuff. Just dark grey ash.
Average run - 35 minutes - NO buffer (Pelpro said it would go to about 50-75 minutes with a buffer.) No time no money this year.
System faults - 0
Problems - 0
Happy wives - 1
OIL USED - 0

System has been run on low since install and we have had two nights beolow 10 with showers in the morning still kept up.

All in all, I am really happy.


I'll keep you posted...
 

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Good to have another conversion on board. I have been running over a year now with my PELLX conversion and I am very happy. I did go through 12.5 tons of pellets last year for all my hot water and heating needs. I run all year. This year I am adding my own pellet making project. I just ordered my pellet mill and expect to be making pellets in the next couple of months. Good luck to you.
 
That's great that you're having success with your pellet burner. Your fuel bills will probably be about half of what they would otherwise be if you were still burning oil.

One thing I notice in your description is a relatively high stack temperature. The stack temp should ideally be between 300 and 400 degrees Fahrenheit, with the lower half of that range being preferable. When you retrofit a pellet burner to an oil boiler, you have a situation where the match between the two may not be ideal. Oil boilers tend to be oversized relative to the norm of pellet burners, which is 20kW. Therefore, hot flue gasses can shoot right past the heat exchanger without coming into contact and transferring heat through the heat exchanger to the boiler water. This effect becomes even more noticeable when pellet burners modulate to lower power levels as they normally do when they approach the high limit.

A pellet burner is ideally suited to a boiler designed for using pellets. That is, the boiler and burner are sized together like clothing is to a person. A pellet boiler also has a bin where ash can collect out of the way of the combustion area, and a large combustion chamber for good combustion efficiency. A good pellet boiler is designed to be easily brushed clean. Oil boilers are designed for annual cleaning, and will have ash blown into places that are hard to get at.
 
I also look into these, now since I have my Harman 105PB I can't see how effective these work .Plus You couldn't keep a oil burner clean enough burning pellets.
 
You can see my unit that I converted last year; photo’s earlier in this post. Note the heat exchanger that was previously used for Fuel Oil and how some carbon was still on the unit. That carbon has burned off and now the only thing to clean is some fine ash that brushes off with a shop brush. Please notice that the entire front of my boiler opens on the right side where the pellet burner is now located, giving me complete access to the heat exchanger and the ash dump in the bottom. This allows access like reaching into a kitchen oven.

My flue temperature is near the 150 F mark during the middle of the burn cycle, it doesn’t seem to get any hotter. All of my controls regarding the burn, the automatic start, self cleaning, pellet delivery, turn on and turn off are regulated by the pellet unit that is separate from my boiler. The boiler controls the distribution of the heated water through 5 zone pumps and my domestic water through a 6th zone pump; this is separate from the pellet controller. The only item that goes from one unit to the other is a temperature probe and a safety aqua stat. This is like having an Oil burner to heat my house.
 
Geo. said:
A pellet burner is ideally suited to a boiler designed for using pellets. That is, the boiler and burner are sized together like clothing is to a person. A pellet boiler also has a bin where ash can collect out of the way of the combustion area, and a large combustion chamber for good combustion efficiency. A good pellet boiler is designed to be easily brushed clean. Oil boilers are designed for annual cleaning, and will have ash blown into places that are hard to get at.

Spoken like a true salesman. I've got $3000 in the install and it works great. I told the guys at Pellet-Pro and they disagreed. They said that the pellet burner was originally designed to replace oil burners in Sweden and that is why they work so well in conversions. They did say that boilers designed and optimized for the burners came later, but how much do you want to spend?

I talked to the guys at Pellet-Pro about the stack temp and they said that it needs to be above 325 with 32' of masonary chimney. That stack temp is actually lower than my oil boiler. They did recommend that I adjust the draft damper and that brought the stack down to about 340 when it is running on low.

It has now been colder than my orignal report and I can say that I still have not had to put it on high fire. It has always kept up. the coldest night we have had was about -5 and the burner on low started 5 times from 8:00PM - 8:00AM. Consumption for the coldest total day of about 0 degrees was 2.5 bags with kids and showers.

Did fault for over temp but it was my fault. did not clean the slots between the sections. As I was brushing the scale off, I actually plugged them without noticing. I thought a 3 pass meant that all of the heat went all th way to the back, and then the front and then the back. Didn't realize that it went up between the sections as well. Completely my fault.

A buddy of mine put one in too and he said he has gone from 1-1 1/2 bags in his big pellet stove plus 750 gallons of oil to 1 1/2 - 2 bags a day. He is over the moon.

I'll get some better numbers when my third ton is done.
 
Congrats on your unit. I am very pleased with my unit also. I had my go round with George also and he seems to only sell the full system and not so much into conversions. I think that the full system is great if you want to spend 8-10 grand or more but I switched to save money not to spend it. Will you and your friend take the next step to making your own pellets? Do you plan on using the boiler all year as I do or shut it off in the summer? Is your unit a self start, self off like an oil burner or is it the high/low/pilot burn type? Have you tried different pellets? I just tried Dry Creek and they are a higher density pellet that required me to decrease the amount for auto start and the amount for full burn. This is the first time I needed to adjust my pellet feed down for a change in pellets.
 
Th Ulma is similar to the Pellx in the on/off. Difference is that Ulma uses a different element that is ignited and on low in about 70 seconds.

Not sure on runnning in the summer. I'll try it and see if it is more hassle than the savings is worth. I only burn about 75 gallons from April - September becuase i have a camp.

As for making pellets and changing brands, I am a forester and also researched it a lot and contrary to popular belief, you want to burn softwood pellets. They have more energy because of the pitch and have less ash because of the cell fiber structure. the guy at Pellet-pro said that softwood is about 1/2 the ash and they are the same density because of the pressure needed to push the wood through the die. (Siad that they have a pellet mill across the road from their offices) so they are pretty familiar with the process. He really recommended their pellets (Northeast Pellet) but we don't have them down this way.
 
I really appreciate your sharing your experiences converting your oil boilers to pellets. I was looking into doing this at my place and was particularly interested in the ease of switching from the pellet gun to oil burner if necessary. However, after talking to the folks at Pellergy we concluded my oil boiler is simply too small. Looks like both of you have sizable, older oil boilers. Plus, my current boiler is in a utility room I made in a crawl space. When I dug out the area for this room I was installing my hydronic system and sized it for my boiler, water tank & condition equipment but never thought about including enough space for a pellet hopper. It would be a task feeding and maintaining with the current access. I did speak to George about his systems and found him to be very informative and helpful so yes, he is a salesman, but he shared a lot of time and useful information, including on Christmas eve, so don't bash him too hard. I ended up putting a Harman pellet boiler in my barn and running 100 feet of insulated pipe to the house. Just completing the install this week. If everything works fine the oil will be backup, only being used when I am away and the Harman goes cold.

Please continue to inform us about the performance of your conversions. I haven't given up. I'm keeping a watch out for older boilers that might be suitable for a conversion. If I find one, I'll consider putting that in. I'm also interested in the units that use the gun in combination with a gasifier and I haven't written off getting one of George's packages. The Harman was purchsed with the possibility that it will to another location currently heated with heat pumps and propane. I think the Harman will do a nice job there, but the guns you have installed seem to be a more efficient option and I have plenty of space in my barn to add water storage if I want to see if that optimizes performance. Blackslax, I must have misst it--where did yoiu get that pellet hopper?
 
ive been looking at a pellx conversion. and from what i've read in this post, it will work in a biasi 3 wood 6. just have to cut a hole in the front for the head. am i on the right track
 
ive been looking at a pellx conversion. and from what i've read in this post, it will work in a biasi 3 wood 6. just have to cut a hole in the front for the head. am i on the right track
 
Another update on the Ulma.

6 tons got me from Novenber to April.

I decided to run the unit for the summer since I sold my camp and went 14 weeks on 1 ton of pellets. Not as efficient as oil in the summer, but still cheaper.

Had a couple of faults - all due to forgetting to fill the bin.

Lost the photoeye. for some reason it said it always saw light. They were quick about replacing it under warranty.

The finish started to flake off the downtube a bit, but just cosmetic.

Have cleaned the burner once this summer and probably should again.
 
ive been looking at a pellx conversion. and from what i've read in this post, it will work in a biasi 3 wood 6. just have to cut a hole in the front for the head. am i on the right track

I was on the pellet-pro wabsite to get thier number when the eye failed, and it said that they are now listed with the 3Wood.
 
I am converting a Laars Newport oil boiler to the ULMA 2000TC. I'm confused how to connect the aqua stat (currently connected to the oil gun) to the ULMA, though. It is a two-wire (black and white). The ULMA has a connection for AC but I'm pretty sure that is supposed to go to a dedicated (and constant) power source. Any advice?
 
Great to hear you are happy with your conversion! Could you offer some advice to a newbie? I'm trying to convert my Laars Newport oil boiler to ULMA, but can't figure out how to make the electrical connections. Specifically, how do I connect the existing aqua stat to the ULMA? My oil gun has two wires running to it, that is all. Doesn't the ULMA require a constant power source? If I just connected the existing two wires, it will receive power only when the aqua stat calls for it. Thanks in advance for any advice!

-Matt
 
New update.
I torture tested my Ulma this fall (whick means I didn't clean it when I knew I should) and it finally shut down on me today. I was actually suprised at how full the main chamber was and the heat exchangers as well. It was not pretty, it was actually about 2 1/2 gallons of ash in a Vega 4-section. I knew it was dirty because I was using more pellets than usual for the weather.
All in all, I am still really happy.
 
Great to hear you are happy with your conversion! Could you offer some advice to a newbie? I'm trying to convert my Laars Newport oil boiler to ULMA, but can't figure out how to make the electrical connections. Specifically, how do I connect the existing aqua stat to the ULMA? My oil gun has two wires running to it, that is all. Doesn't the ULMA require a constant power source? If I just connected the existing two wires, it will receive power only when the aqua stat calls for it. Thanks in advance for any advice!

-Matt

Good to see you here. I expect that your electrical question was taken care of by Pellet-Pro. Best advise I can give is get to understand when your boiler can, should, and must be cleaned. Those are 3 different times to be sure. Holding your hand on the downtube below where the flex tube goes in will tell you.
When it is OK, it will be warm.
When it can be cleaned, it will be hot but comfortable to the touch.
When it must be cleaned is when it is hot any uncomfotable.
You can keep your hand on it, but it is hot.
If you can't hold your hand on it, it definitely needs cleaning.

Another way to tell is to pull the downtube out while it is running.
Twist it out gently so that the dust does not grain elevator back up the pipe (lesson learned).
Once it is out, smack the pipe to let the dust out in your hand.
If it is pushing heat out the pipe, probably time ot clean it.
 
We've been running the newest ULMA conversion with our Laars Newport for a month and LOVE it! Just gave the boiler a good cleaning this weekend and look forward to a cleaner burn. Still waiting to get someone in to measure our chimney gasses. http://www.pellet-pro.com is AWESOME! GREAT customer service... If you are looking to make the switch, I strongly recommend Tim at Pellet-Pro.image.jpg image.jpg
 
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