Direct connect combustion air - Wood Gun E100

[Pontypool]

OK, good morning - its Saturday morning.
Outside temp is 10.5 F, house temp is 71.5 (set back temp for sleeping), WG is 169F - wood is burnt but coals are very hot - still on "RUN" - no need to use "start". Add kindling - self ignition. Wait for some flame - add 2 cheaters and a smaller split - that will slowly (1 1/2 hour) bring the house back up to 78 and lasted until 2 pm - also satisfying DHW for showers and a load of laundry. see pics.

Wood burnt this season shows the part pile (which was full likw the one behind it. ALSO there was another 1/3 of a row of odd splits & stump cuts - which caused me alot of grief with huffing. That is what I have burnt since Dec 17 when I first fired the WG.
Still working on the heat recovery - still looking for ideas

 

[infinitymike]

Yes split size does matter, hence my video I posted earlier. All though I have no field experience with the large splits, you, among other with WG owners i know, are proving my theory.
It looks like a lot of what I'm burning would be considered your cheaters.

 

[avc8130]

I've just been splitting larger and larger the longer I own the WG. Pretty soon I'm just going to be bringing whole trees in and feeding them in slowly through the loading door as they burn.

ac

 

[muncybob]

Pon ty, maybe I missd something along the way here(would not be the 1st time)...do you have your firebox "floor" lined with brick?

 

[infinitymike]

I've just been splitting larger and larger the longer I own the WG. Pretty soon I'm just going to be bringing whole trees in and feeding them in slowly through the loading door as they burn.

ac

TRUE THAT!!

 

[Pontypool]

Muncybob - my WG is factory original - did not add anything, no extra bricks. What you see in the photos is the way
it was built - why do you ask ? does my WG look different in the pics???

The beauty of larger splits with the WG is they can be as dry as you like - no huffing.
Mike - you may want to keep some of that small stuff for cheaters once you start using larger splits - all my wood is large so I am making cheaters with an axe in my basement - not really fun. I find the cheaters are gone mostly inside of an hour when I slide one under a large split, but its enough to get the large split burning real good. I get about 6 - 8 cheaters out of a large split, but like you have been saying - its all about surface area (I am listening)

I find that I have to check the fire more often when burning only 1 large split at a time, and have to randomly add cheaters as sometimes a single large split will just not really burn vigorously - usually after everything is up to temp and there is an extended off time or firing from cold (125F) and the refractory is not fully up to temp. So it is a little extra work checking more often and "settling" the piece on the refractory occasionally - but it sure is saving wood, and I can go a full 7 days and the ash pan is not completely full - bonus! Keep in mind - the Wg blower runs a little more when only burning 1 piece, and will run 3 or 4 hours starting from cold, but my electricity bills are still much lower.

Worth noting also (or maybe not) my pics show my wood pushed back into the chamber - thats just so I can show the size of the pieces. Before I shut the door, I pull all the real wood to the front so it is right against the door frame and make sure the nozzle at the back (under the air supply) is open and not covered - I basically don't use the last few inches at the back so air can get in. Also I "fit" any pieces together so the fire has to burn thru the bottom ones to get to the top ones (saturday morning load pic), so basically that saturday piece was in there for 2 hours before it really even started to burn - cheaters got WG up to temp, cycle off, then larger split starts burning when Wg cycles on again, but in the mean time the larger split has been heated (cooked) without using its own mass.

 

[muncybob]

It may just be me, but pic 2739 sorta looks like the nozzle has one continuous slot?

 

[infinitymike]

It may just be me, but pic 2739 sorta looks like the nozzle has one continuous slot?

That's 2 long cheaters laying next to each other.

 

[infinitymike]

Truth be told I have been burning the really big splits during the overnight. I fill the box half way with the small splits and throw 2 or 3 large splits on top.

 

[Pontypool]

Well, I am just over 2 months burning my WG, probably burned a full bush cord now - center bricks are done.

I have been making inquiries about what to replace them with. Talked to Mike at AHS - apparently I have the "old style" which were not very good - really??? - looking at about $110 + shipping & customs - so probably about $200 for the new, improved bricks to arrive here.

AHS is also selling steel 5/8" replacements with wings to hang from the refractory and sit above the slot shoulders - those are about $50 more and Mike says they don't last any longer than the regular bricks.

I met with our local steel fabricator, quite an experienced man. He suggested steel brick will probably wear as quickly as refractory brick and there is a possibility, at gasifier temps, that the steel "brick" could distort enough to cause damage to the refractory slot. Arrrrrggg.

Right now I am sourcing a diamond encrusted router bit so I can cut slots in regular (wood stove style) refractory bricks.
Looks like the bit will cost close to $100 locally and bricks are $2 each - need 3 for an E100. If this were to work the second set of bricks I make (and all the ones after that) are basically free - compared to buying from AHS.
See pic for my layout - bricks in the pics are my spares I bought with my WG.

Has anyone tried this? Any pearls of wisdom anyone can impart here would be appreciated.

 

[infinitymike]

Well, I am just over 2 months burning my WG, probably burned a full bush cord now - center bricks are done.

I have been making inquiries about what to replace them with. Talked to Mike at AHS - apparently I have the "old style" which were not very good - really??? - looking at about $110 + shipping & customs - so probably about $200 for the new, improved bricks to arrive here.

AHS is also selling steel 5/8" replacements with wings to hang from the refractory and sit above the slot shoulders - those are about $50 more and Mike says they don't last any longer than the regular bricks.

I met with our local steel fabricator, quite an experienced man. He suggested steel brick will probably wear as quickly as refractory brick and there is a possibility, at gasifier temps, that the steel "brick" could distort enough to cause damage to the refractory slot. Arrrrrggg.

Right now I am sourcing a diamond encrusted router bit so I can cut slots in regular (wood stove style) refractory bricks.
Looks like the bit will cost close to $100 locally and bricks are $2 each - need 3 for an E100. If this were to work the second set of bricks I make (and all the ones after that) are basically free - compared to buying from AHS.
See pic for my layout - bricks in the pics are my spares I bought with my WG.

Has anyone tried this? Any pearls of wisdom anyone can impart here would be appreciated.

There's NO WAY you center bricks can be DONE with only burning for 2 months and just over a bush cord, which by the way, I have no idea what a bush cord is. I only refer to cords that equal 128 cubic feet. So if a bush cord is 20 times more than that , then you're ready for new center nozzles.

Do you have a picture of the center bricks?

You only need to worry if the center brick is so worn that it is effecting the shelf they sit on.
AHS sells the steel plate for units that have worn out the shelf and can't support the bricks.

 

[Pontypool]

Bush cord - a pile of wood measuring 4' H X 4'W x 8'L - so 128 cu/ft
Face cord - 4'H x 16" W x 8'L - 1/3 bush cord.

Tomorrow is my weekly WG cleaning day - I will take pics looking up from bottom. Cannot remove or they will
fall apart. May have another week or two, but they are done, every week they are noticably worse. Yeah, I can't believe it either. My thinking is to replace the center bricks BEFORE the shelf is affected at all as the refractory is a much bigger deal ( $ and time) than the bricks. My understanding is the refractory cost about $750 so I am looking at $1000 delivered - minimum.

 

[muncybob]

1 cord and the nozzle is shot!!?? Even with the "old" style nozzle I got 2 seasons which would have been about 9 cords.

 

[maple1]

Forgive me for not reading back through the thread again - but I believe this boiler sat for quite a while before it was commissioned? Wondering if the refractory soaked up a little more humidity than usual in that time (depending where it sat, maybe), then if fired hard before they had a chance to get rid of the moisture properly (from several very small fires) their life may have been shortened? Hard to figure how else they would only last one cord of wood.

 

[Pontypool]

From page 5...........(with a few edits)....
All the plumbing for my WG was completed at the beginning of the heating season this year (September2014) but there were some finishing touches so I was heating with a regular forced air natural gas furnace. I was running my circulators while the gas furnace was running, circulating fluid through the hot/cold coil in my main duct. In effect I was "stealing" heat from the forced air system which (after about 2 hours running) would heat the entire hydronic system up to 120F - including the WG - that should have done some drying/curing - you could feel the warmth wafting out of the burning chamber and tubes - I did this for weeks. I did have small fires 3 days in a row before putting in larger loads - but then, I have never had more than about 4 pieces of wood in my WG at one time.
..............Also, the WG sat in my basement, from purchase to commission, which is dry (for a basement).

Also - since my post on Feb 9 - my green light quit- SERIOUSLY??? - good thing I have bad luck or I'd have no luck at all.

Sooooo....... no one has tried or knows of anyone using wood stove style firebricks for center bricks?

My understanding is that they are good for sustained 3000*F, designed to hold heat (very heavy) and design to withstand endless (maybe not endless - but alot) heating/cooling cycles. The trick will be making the slots, then to see if the brick has been weakened too much.
Never know if I don't try, but was hoping someone already had some experience with this.

Still working on heat recovery from the cyclone - now on third try - working on a MUCH SLICKER design now - alot of work - if there is a way to do this, I will find it, - pics will follow when I get that far.

 

[avc8130]

Pics of the nozzles please.

My Green LED died a quick death also. Inside my control box were 2 spare bulbs. I put one in and it's been working since.

Try the fire brick, let us know. My guess is that it won't handle the erosion as well as the refractory nozzles. You could also try making a steel plate to lay over then nozzles.

My original nozzles are going through winter number 3, probably right around 24 cord (4x4x8). I'll replace them after this year. My old oil boiler required an annual $125 service...so far the Wood Gun has been pacing similarly to that annual cost.

ac

 

[Pontypool]

I will check my control box tonight, but didn't see any leds (could easily be missed) when I was wiring it up.

I have no idea if refractory brick will hold up but even if it lasts a half season it would be far cheaper than the AHS bricks. AHS bricks delivered - one set- $200 - fire bricks $2 each (buy them anywhere) and $100 for a diamond router bit - having one custom made for this purpose - ordered this morning. I think its worth a try - nothing ventured - nothing gained.

If that works - these bricks are also readily available in 2" thickness for $2 - will measure the main tube tonight - one brick could also be easily carved with a $2 diamond grit 4 1/2" grinding wheel in an angle grinder to replace the plug when the time comes. Mine loses a thin layer every week when I take it out to vac the tubes - I handle it like precious china.

Doing my weekly WG clean tonight - pics tomorrow.

 

[infinitymike]

I'm on my second set of center brick nozzles.
I burned the winter of "11 and "12, the summer of "13 then changed them in the winter of "13, probably 24 cord 4x4x8,
I burned the rest of the winter of "13, the summer of "14 , the winter of "14 and now into "15, probably 15 cord and they show very little wear.

 

[Pontypool]

No spare LEDs included with my WG.

So I cleaned my WG last night - and changed the center bricks to the second set I bought with the original purchase.
I have burned since Dec 17 2014 - just barely over 1 full cord (bush cord that is-4x4x8 -its a Canadian thing).
I could not get very good pics from the bottom where the wear was the worst. I removed everything without tools - it just came apart.

 

[Pontypool]

I had to cut the small brick to get them to fit. The dimensions were correct but they are so crooked - every side is different - that they would not butt up squarely. Seriously - look at the bricks - thick & thin, different dimensions, the nozzles are not even close to center or straight????? Not giving me any confidence when I see that kind of work.
$120 for such poorly made bricks?????
It was time to replace these - the small brick might have lasted a while longer, but the long brick was done.
I can squeeze and break it up with one hand. Not impressed. Makes me want no run out and buy some more -NOT!

Its all fine and well it they have changed the formula now, meaning they know there was a problem with the old ones.
Same with the gaskets on the doors, Oh, we don't do it that way any more. When you spend $10k on anything, you expect to get some reasonable use before you start replacing things. I am not considering this anywhere near reasonable.
As soon as I can make up my own center bricks, these ones will be coming out. Hard to see in the pic but the slots are all over the place, some on a noticeable diagonal - the flame will be hitting the refractory shoulder in places - the slots don't run down the middle. I already have one corner of the refractory deteriorating because one of the slots in the original bricks was on a diagonal, so the flame ran right down the face of the refractory shoulder.

 

[avc8130]

Ponty,

Just to add an outsiders view:

Had you installed the boiler and started running it remotely close to when you bought it, you would have experienced all of these "shortcomings" very early on and I'm sure AHS would have helped you through them.

I spent close to $10k on my boiler. I put it into service 6 weeks after I bought it. I have not had trouble with door gaskets. My nozzles are on their 3rd winter.

I agree your nozzles look pretty "shot". Mine look NOWHERE near that bad after 20+ cords, so they MUST have changed the formulation for the significant better.

ac