Garn WHS3200 & Wood Gun E500 – Another Night Out [Part 7]

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Warning, we are teetering on the precipice of a dangerously hot topic!

You're right, and maybe a topic many of us would like to pursue. BUT PLEASE NOT ON PART 7 OF MY GARN/WOOD GUN THREAD! :mad: I would appreciate the Garn/Wood Gun threads to be mostly on topic. Thanks. Cheers.
 
jebatty said:
MC and transportation costs are the gorillas in the room for wood chips. Unmerchantable timber can be chipped at the logging site, which is economical, but then transportation to the user site gets prohibitive, as compared to the delivered cost of other fuels, at somewhere between 40-100 miles, depending on the local economics.

But what a "waste" to dry the chips using btu's from the combustion process or other energy than letting the sun and wind dry for free. I can only imagine how much worse the economics are when transportation to a drying site, handling, and the transportation to a user site are involved. In my area unmerchantable leftover from logging is either given without additional charge to the logger (built into the logger's bid price for the timber) or at a very small surcharge.

For residential use especially other issues are storage and freezing. High MC chips could become a hard, frozen mass when needed most.

I'll be the first to say that chip feed systems and boilers that use them are economically viable only on a load of half a million btu's (constant) or higher. When you get past that point you really start tallying serious labor costs with cordwood and need a small army and a system to process/handle basically 1 cord per day of operation. I have a couple people (industrial type use) that are going through 70-100 full cords per year and it is basically a full time job for one person plus additional labor for around the clock firing during the winter.

When chips are stored in large silos or even piles on the ground, they tend to create their own heat due to low level "spontaneous combustion". This is precisely because of the high moisture content. Those of us in farming communities know what happens when you put wet bales of hay in the hay mow of a barn. Same thing with the wood chips. The local co-gen plant has actually had their outdoor pie of chips catch fire a couple times.

Interestingly, much of the fuel for both of the local plants 14MW and 30MW IIRC, is processed in the UP of Michigan and trucked all the way down here. In some cases I am sure that the trucks travel as much as 300 miles one way and of course go back empty. Seems pretty expensive at 6mpg for one of those rigs. The company that supplies the 14MW plant has 9 semis on the road every day. Cost of the wood product itself must be very cheap.
 
Jim,

Thanks for posting the information on your "nights out" with these two large output wood boilers. I appreciate it.

Being a Wood Gun owner, I find them interesting. And I would like to ask you a few questions about the boilers at the Deep Portage facility.

1. How old is the Wood Gun?

2. How often does the ceramic nozzle on the Wood Gun have to be changed? And. Have you changed the nozzle yourself? How was that for a job?

3. How often do the boiler tubes get cleaned?

4. What is the typical M.C. of the wood being burned in the Wood Gun?

5. What species of wood are being burned through the Wood Gun?

6. How often does the Ash cyclone pan get cleaned out?

If you could add any things learned about preventative maintenance with the Wood Gun here, that would be greatly appreciated. Any problems experienced, lessons learned, problems solved, etc.

I do not know the Garns. But am curious about them.

1. How old is the Garn?

2. What does the Garn have in it's chamber? Is there a nozzle?

3. How often do the boiler tubes get cleaned in the Garn?

4. What is the typical M.C. of the wood being burned in the Garn?

5. What species of wood are being burned through the Garn?

6. How often are the ashes cleaned out of the Garn?

7. Is there a system in the Garn to do that similar to the Wood Gun?

And for the Garn owners out there. If you could add any things learned about preventative maintenance with the Garn here, that would be greatly appreciated. Any problems experienced, lessons learned, problems solved, etc.

Oh. What does the facility do with the Ash that comes from burning all that wood? I can not imagine the amount of Ash if they were not Gassification boilers! I can not believe how little Ash I produce compared to the wood stove. And that is a newer model stove with a "baffle" that creates a secondary burn in it.

Again. Thank you Jim. I appreciate the postings you do on these Boilers.
 
jebatty said:
Warning, we are teetering on the precipice of a dangerously hot topic!

You're right, and maybe a topic many of us would like to pursue. BUT PLEASE NOT ON PART 7 OF MY GARN/WOOD GUN THREAD! :mad: I would appreciate the Garn/Wood Gun threads to be mostly on topic. Thanks. Cheers.

jebatty said:
I would support social costing of nearly everything. There is no free ride. The grim reaper waits ....

jebatty said:
... I will disagree on the long term effect of fossil fuel contributed CO2 buildup ...

Whatever you say, after all it is your thread to police, and obviously you know better than any what is on topic and what is not. Sorry for intruding.

Cheers --ewd
 
EW -- got me on those. Plea is guilty. As mentioned above, a topic many of us would like to pursue. A thread of its own would be great, if the Mods will let it float.
 
Gasifier -- I will take all of your questions to the man in charge. I know some answers, but I'll let the guy responsible provide the answers. Will be a day or two before I can respond.
 
jebatty said:
The Garn specs show 700,000 btuH maximum output under specific conditions. The test burns last winter indicated on a continuous, not maximum, burn basis sustained output was in the region of 500,000 btuH.

[added] For my Tarm and based on 5 years of operation I use rule of thumb average output over a burn of 75% of maximum rated output, which for the Tarm is 140,000 x 75% = 105,000 btuH. This seems to also be about right for the Garn: 700,000 x 75% = 525,000 btuH.
Jim, I hope I can ask of Dectra to clarify outputs of its boilers without sidetracking your thread. Frankly I'm shocked that what was a million btu boiler now puts out a continuous 500,000 btu. Mr Lunde? Randy
 
Gasifier, here are answers to your questions. Hope this helps.

General information:

About 85-90 cords are burned each heating season. In seasons 2009-2010 and 2010-2011 the Garn was used more than the Wood Gun because the Garn was so easy to operate and because of operating issues with the Wood Gun. Those issues were finally diagnosed as improper installation of the boiler return water protection valve and lack of storage. This season (2011-2012) the Wood Gun is being operated much more than the Garn. The Garn has been used primarily as a supplement to the Wood Gun and in mild, low heat demand weather.

With the correction of the valve problem and adding 4000 gal storage, the Wood Gun is about as easy to operate as the Garn, and it quickly delivers 140 to 180F water to the system through the hydraulic separator storage tank. Most of DP's emitters are large air handlers and cabinet style unit heaters which require water in this temp range. The Garn, with its integral 3200 gal of water, takes a fair amount of time to heat to 140+, and this slow response makes it less practical in meeting DP's needs. Also, as experience last winter evidenced, the Wood Gun is well suited to both batch and continuous burns. The Garn with its integral storage is well suited to batch burns.

1. How old is the Wood Gun?

Purchased and installed in 2009.

2. How often does the ceramic nozzle on the Wood Gun have to be changed? And. Have you changed the nozzle yourself? How was that for a job?

Then nozzle was changed after two years. Work done by the lead operator at DP. Not overly difficult, but some of the ceramic pieces had to be trimmed to fit.

3. How often do the boiler tubes get cleaned?

The middle tube is cleaned weekly, the two side tubes stay clean, access and cleaning is easy. Purchased and installed in 2009. The bottom ceramic has been changed once.

4. What is the typical M.C. of the wood being burned in the Wood Gun?

Estimate is 20% +/-. Most wood is split, stacked and dried 1+ to 2 summers.

5. What species of wood are being burned through the Wood Gun?

Red oak, birch, maple, ash, some pine and aspen.

6. How often does the Ash cyclone pan get cleaned out?

The E500 has a 55 gal barrel to collect ash; fills up about every 5 weeks.

If you could add any things learned about preventative maintenance with the Wood Gun here, that would be greatly appreciated. Any problems experienced, lessons learned, problems solved, etc.

Since 4000 gal storage was added summer 2011, plumbed as a hydraulic separator, and has been operating this 2011-12 heating season, no problems at all. Prior problems were related to improper installation of the boiler return water protection valve, lack of storage and idling, and extreme puffing.

I do not know the Garns. But am curious about them.

1. How old is the Garn?

Purchased and installed in 2009.

2. What does the Garn have in it’s chamber? Is there a nozzle?

The bottom 1/3 or so of the fire box is lined with fire or ceramic brick, no nozzle, but the fire tube out the back of the fire box is ceramic.

3. How often do the boiler tubes get cleaned in the Garn?

Monthly to seasonally. Two access ports need to be removed, not as easy to clean as the Wood Gun.

4. What is the typical M.C. of the wood being burned in the Garn?

Same

5. What species of wood are being burned through the Garn?

Same

6. How often are the ashes cleaned out of the Garn?

A good ash bed is left in the fire box. A shovel full or two of ash is removed from the fire box after a burn and prior to start of the next burn. Ash volume is about the same as the Wood Gun.

7. Is there a system in the Garn to do that similar to the Wood Gun?

See prior answer.

What does the facility do with the Ash that comes from burning all that wood?

Ash is spread lightly in open field areas.
 
Thanks Jim. I appreciate it.
 
More questions for you Jim....I assume they have had to replace the fan bearing on the WG? How many cords did it last and was it a fairly easy job? I don't recall the return water temp problem, what was it and how was it addressed? Thx!
 
I will check on the fan bearing. I believe there were some fan problems, and will find out more. The return water protection problem involved the incorrect installation of a motorized 3-way valve to provide the 160F return water. It was installed incorrectly as a diverter valve and the Tekmar controller also was improperly installed. The effect was to inhibit the WG's ability to deliver its load of hot water, resulting in the WG idling extensively unless very careful attention was given to the wood load, and therefore to cause staff to use the WG as little as possible.
 
FWIW Gasifier, I clean my Garn HX one a year....takes about an hour...couldn't really be any easier. Remove the "cover plate" from each HX tube and brush it out. I remove ashes from the firebox with a square point shovel....about once a month.
 
Just a thought, do any garn owners clean the tubes with the fan running?

I clean the three before the fan with the fan running, then attach an old sawdust collector fan to the chimney with a fernco and clean the rest. Works great to keep the fine dust moving outside.
 
bpirger said:
FWIW Gasifier, I clean my Garn HX one a year....takes about an hour...couldn't really be any easier. Remove the "cover plate" from each HX tube and brush it out. I remove ashes from the firebox with a square point shovel....about once a month.

That is "worth" a lot bpirger! For the amount of money we put into these heating systems, we need them to be easy. I have a little over $13,000 into my system. That's a lot dough. But, I have used maybe 5 gallons of oil since October 1, 2011 keeping a 4000sq.ft. house, 900sq.ft. attached garage, and our DHW for 6 people warm. I am guessing you probably have that much into your Garn and needed paraphenalia of pumps, piping, fittings, etc. The Garn sounds like a real nice boiler. Big. But nice. I had considered it. But I wanted the detached garage I built for storing my toys, I mean, my equipment that is needed for the required work to get done around the house and the family property. So, boiler and storage need to fit into basement. As far as I am concerned we are all lucky that these nice wood and pellet burning boilers and furnaces are available to us.
 
muncybob said:
More questions for you Jim....I assume they have had to replace the fan bearing on the WG? How many cords did it last and was it a fairly easy job?

There have been no bearing problems with the WG fan. When the WG was installed, the contractor dropped the fan motor and bent the shaft. The motor was replaced and no difficulties since.

The Garn supplied motor failed twice, and Garn replaced without charge. Then the motor failed a third time. Garn advised that problems had been experienced with the motor and it furnished a new motor of a different design, this time at DP's expense. That motor was installed at the start of the 2011-12 heating season. So far it is good.
 
The comments on various users' experiences are good. I think it is important not to compare different models of the same boiler and expect valid comparisons, as operations, cleaning, and performance may and likely do vary between models. For example, bpirger cleans his Garn once per year, but he has a 1500. DP has a 3200, and at times DP may burn up to nearly a cord per day. Obviously, cleaning requirements will be different with this intensive use vs bpirger's use and experience with the 1500.
 
Jim, point taken. I did inquire about the fan bearing only because my owners manual states to expect to replace it every 15 cords or so. I wonder if DP's unit is even the same motor/bearing. I'm guessing it's not. I can't imagine burning a cord/day though...that's a helluva lot of wood!
 
Seems an odd way of measuring it, loke servicing your truck depending on how many gallons of fuel you have used.
 
I took it to be clear that the 3200 was seeing A LOT more wood then my 1500. I burn maybe 1 cord a month,...so there you go. My point in saying once a year with my 1500, and cleaning out ashes once a month (or less often likely), is to give the reader interested in his own use a range of parameters. DP is obviously an incredible cool (or hot!) installation and application....but it is also an extreme application...compared to the homeowner.
 
Como said:
Seems an odd way of measuring it, loke servicing your truck depending on how many gallons of fuel you have used.

Not sure how else they could state it except to say it's an expected periodic maintenance item. I'm hoping to make it through our 4th season(next year), we should be well above 15 by then. Also hoping it's an easy job!
 
I too burn about a cord a month, however i clean the flue tubes with a wire wheel and drill extensions every 6 weeks, It takes a very thin layer of flyash to insulate the fluetubes. There is 30degf +/- drop, well worth the 20 minutes of cleaning.
 
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