Thinking Wood Gun...any advice or experience?

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It's not just the refractory that needs to be hot but the coals themselves as well.
I'm not a physicist but I'm sure the coals have to have a lot of potential energy too.
All I know is the the fire is definitely extinguished and the coals are black. And then there is a fire.

I guess the wood gun has little fire gremlins that live inside the firebox. AHS never marketed those guys! ;-)
I have no doubt the coals are black. I think you're trying to re-write the laws of physics saying the wood is OUT.. Then starts again only using air and heat. Gotta have a spark there. The spark is in the wood! you just can't see the coals still going.. IDLING! :) would be the word I would use.

Now.. your wood gun may be OFF, more than my vigas sitting in MAX mode... and occasionally turning the fan on to KEEP the coals alive.

Why do you think firefighters douse the hell out of a fire site? There's all kinds of coals buried in the fire that could relight with a little air and time. I get that the wood gun cuts off the air.. but I don't think wood fires have an on/off switch.

:)

I'm sure it's a good boiler. I chose a different one. I think we'll both be warm this winter.

JP
 
There is a wire in the electrical box that I had to disconnect to stop the fan from running. I ran oil the other day to appease the Mrs one cold morning since I didn't have any wood in the house and by the time it got to 180*(about 30 min.) my stack temps were running close to 750! Won't do that again.

I plan to install my oil setup as a complete stand alone control system. My main switch will completely un-power the WG fan/intake motor and power up the oil setup. There is no way the fan will be on.

I'm surprised by that stack temp. The volume for the oil burner to work in is quite large, but I guess the oil has trouble putting heat INTO the refractory like the wood does. Instead it relies on putting heat into the dedicated exchanger. BTW: the E180 has a significantly different oil design than the 100/140.

ac
 
I think it really depends how you define "fire".

Noun:
Combustion or burning, in which substances combine chemically with oxygen from the air and typically give out bright light, heat, and smoke.

With no source of oxygen, that seems like that definition would be impossible to meet. The starting of a fire is done when the medium is brought to its ignition point in the presence of oxygen. The refractory maintains the "coals" at their ignition point (572F) and when air is introduced: FIRE.​
Idling is more like closing the damper down ALMOST closed and still maintaining a FIRE.​

 
Like I said before Here we go again! Round and round the merry go round. Will it ever stop or will it just idle :)

Hey what about this Ever rub to sticks together and blow on it? Like the Indians? Hmmm.... No spark, just heat and forced air and then fire! Maybe the guys who created the wood gun have an Indian heritage.
 
Like I said before Here we go again! Round and round the merry go round. Will it ever stop or will it just idle :)

Hey what about this Ever rub to sticks together and blow on it? Like the Indians? Hmmm.... No spark, just heat and forced air and then fire! Maybe the guys who created the wood gun have an Indian heritage.

Well technically you use friction to create a hot coal or ember which you as a source of ignition or the spark to create fire.
 
Wood Has an immolation point of about 745 degrees so if the refractory is below that point there is no way the wood can reignite. Unless of course it was never really out.
 
I won't go any farther than this post about what I think of the Wood Gun because I tried to post my experiences with the unit and was accused of bashing the product.
I will say that after running the beast for 10 years, I concluded that there needs to be a small ember somewhere in the pile of coals in order for the Wood Gun to re-ignite.
Bob is correct in stating that the hot refractory helps support the spark but there needs to be a glowing ember, even smaller than a pea somewhere in there. The speed that the Wood Gun moves the air helps that ember spread rapidly.
I'm sure you learned alot in the year that you have run the Wood Gun but you will know more after you get 10 years experience under your belt.
 
Enough arguing about idling/off. Let's discuss some install options.

My current setup has a Taco 007 pump supplying 5 zones each controlled by a zone valve. Is this a good application for a Grundfos Alpha? From what I understand it sounds like a great idea. Since it is unlikely that all 5 zones call for heat at once, the variable pump should be ideal when only 1 or a few zones call, right?

The 2nd "option" is figuring out how to plumb in the water heater. I will be installing an electric heater to use when I am not running the WG in the warm months. I plan to hook my current indirect up to the WG with its own circuit just like it is off my current oil boiler. I figure there are 2 options to plumb this in:
1. Parallel. This would let me select which system to use and I could drain the other. A few ball valves would make this very easy. This method is simple and would also force me to clear the sediment out.
2. Series. I could plumb the indirect first in line with the electric after it. Then when the WG is running, I could set the aquastat on the indirect high enough that the electric never kicks on (even with standby loss?). If the WG isn't running, the electric would heat only the normal quantity of water it was designed for. This method provides more of an "auto" backup, but may wind up costing me a few bucks in electricity if the standby losses on the electric cause the water from the indirect to go too cold.

ac
 
Enough arguing about idling/off. Let's discuss some install options.
ac

Awh, it was starting to get fun!

Actually I am sorry that your thread got hijacked.

I don't know enough about the engineering mechanics to help with your design. I'm actually still not sure which way to hook up the two indirects that I have.
But what I do know is that there are plenty of guys here that do and are always generous with their time and experience.
 
Awh, it was starting to get fun!

Actually I am sorry that your thread got hijacked.

I don't know enough about the engineering mechanics to help with your design. I'm actually still not sure which way to hook up the two indirects that I have.
But what I do know is that there are plenty of guys here that do and are always generous with their time and experience.

We can keep discussing, but clearly I agree with you and all of the marketing hype. Sealed means no fire. A fire without oxygen defies the laws of physics more than a dormant one restarting at the introduction of heat AND oxygen.

Are you using your WG to make hot water?

How's that video coming?

ac
 
Are you using your WG to make hot water?
Not yet. I did buy the WG with a DHW coil. I ended up with 2 indirect water tanks, one from ebay and one from my plumber for free. Nothing has been hooked up yet. I cant believe its almost burning time again and I still haven't hooked them up.
How's that video coming?
I will start on it pretty soon. Should be interesting to say the least.

ac
 
I'd pipe the two water heaters in parallel. The series configuration will waste electricity because the electric will still come on due to standby losses. The only way to avoid this is to set it up for thermosyphon somehow, the only advantage to that would be a large amount of stored hot water, which it sounds like you don't need. No huge hot tub to fill, 10 consecutive showers, etc. When your boilermate craps out, you can use a sidearm, or flat plate with pump, on the electric. All in one, the elements should never come on during fireing, and if the tank drops, then voila it's got electric backup. Just find out the max temp the tnak can take so not to damage the insulation. And an ASSE 1017 mixing valve.

I call that the poor man's indirect.

TS
 
What does the return water temp protection valve do? This unit is SS, why worry about condensing?

ac

The return temp protection valve prevents cold return water from dumping into the unit and automatically controls the return water temperature, preventing condensation of the water vapor contained in the flue gas. The valve mixes by-pass flow from the boiler with return flow from the system, sending a fixed temperature flow to the boiler which protects against corrosion from condensation occurring when a minimum flue gas temperature is not otherwise maintained. Even though I have the stainless steel firebox also I still installed one. I figured it couldn't hurt. Plus I think it helps get the water up to temp faster.
 
I'd pipe the two water heaters in parallel. The series configuration will waste electricity because the electric will still come on due to standby losses. The only way to avoid this is to set it up for thermosyphon somehow, the only advantage to that would be a large amount of stored hot water, which it sounds like you don't need. No huge hot tub to fill, 10 consecutive showers, etc. When your boilermate craps out, you can use a sidearm, or flat plate with pump, on the electric. All in one, the elements should never come on during fireing, and if the tank drops, then voila it's got electric backup. Just find out the max temp the tnak can take so not to damage the insulation. And an ASSE 1017 mixing valve.

I call that the poor man's indirect.

TS

TS,

I came to the same conclusion about plumbing in parallel, I just wanted to make sure I wasn't missing anything.

When the boiler mate craps out, I will probably just buy the DHW coil for the WG. All WG come with the post to accept the coil, so it will probably be the cheapest option when the time comes.

ac
 
avc, you can then use the DHW coil as the heat source for the electric during fireing. Domestic water circulates through the coil and the electric tank. Like an indirect, but with the coil in the boiler instead of in the tank. It's been done many times in an old oil boiler with a domestic coil, the coil scales up and does not produce enough water anymore, you put in an electric water heater but run the water through the coil in the boiler with a bronze circulator hookes to the electric's thermostat. Worke great, much less $$$$ than an indirect.

The poorest man's indirect.

TS
 
avc8130,

My experience with the wood gun is fairly limited. One year in now. I heat my whole house (4000+ sq.ft.), my garage (900 sq.ft.), and my DHW. I have been heating my DHW all spring, summer, and up to now with one or two short fires a day. I think you will like the wood gun. With regular scheduled cleaning and a little maintenance, I think you will find it to be a good wood burning appliance.

AHS and these fine, outstanding gentlemen on hearth.com who have experience with burning the wood gun can claim whatever they want. As far as keeping your fire going, I have found only a couple of things can effect that on a regular basis: Please see below.













Exercise is good. Stretch first.

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And keep yourself in good shape and spirits. Positive thinking is very important.
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Good luck with the install man. And keep us posted. Pics. Or it didn't happen.
 
avc8130,

My experience with the wood gun is fairly limited. One year in now. I heat my whole house (4000+ sq.ft.), my garage (900 sq.ft.), and my DHW. I have been heating my DHW all spring, summer, and up to now with one or two short fires a day. I think you will like the wood gun. With regular scheduled cleaning and a little maintenance, I think you will find it to be a good wood burning appliance.

Good luck with the install man. And keep us posted. Pics. Or it didn't happen.

Hmm...I am intrigued. You heat ALL of that with a 100? How often are you re-loading?

How does your non-heating DHW work for you? I am hesitant to use the WG for DHW when I'm not heating as I have heard it throws off a lot of heat.

ac
 
I have a friend with a WG 100 and he does all his summer DHW with just it and the coil. One small fire a day, I think. He's very happy with his and it doesn't seem to throw off that much extra heat. I suspect even if you were to just incorporate an indirect tank, you could likely space that out to every couple of days if it was a good size & well insulated.

On all the 'idling' debate - call it idling or call it something else, but from all I have seen & heard & read, my bottom line takeaway is that I think the WG does gasifying without storage better than the other guys.
 
I have a friend with a WG 100 and he does all his summer DHW with just it and the coil. One small fire a day, I think. He's very happy with his and it doesn't seem to throw off that much extra heat. I suspect even if you were to just incorporate an indirect tank, you could likely space that out to every couple of days if it was a good size & well insulated.

On all the 'idling' debate - call it idling or call it something else, but from all I have seen & heard & read, my bottom line takeaway is that I think the WG does gasifying without storage better than the other guys.

How much house does your friend heat with his 100?

I guess he does his daily small fire in the morning right before showers?

My setup will have an indirect. I planned on only using it during the heating season, that is subject to change.

ac
 
I cant seem to find prices for this stove and there are no reviews in the stove reviews section under alternate heating systems,the company name.
 
How much house does your friend heat with his 100?

I guess he does his daily small fire in the morning right before showers?

My setup will have an indirect. I planned on only using it during the heating season, that is subject to change.

ac

He doesn't have a big house. It is just single story, maybe 1200 sq.ft.? (A guess). With full basement. Not sure when he lights, but he said at that point (water too cool to shower with) it only takes 5 minutes of burning and he's got all the hot water he needs. The coil is situated in the right spot for that.
 
I cant seem to find prices for this stove and there are no reviews in the stove reviews section under alternate heating systems,the company name.

It's not a stove, it's a boiler. I think there were prices mentioned earlier in the thread.
 
He doesn't have a big house. It is just single story, maybe 1200 sq.ft.? (A guess). With full basement. Not sure when he lights, but he said at that point (water too cool to shower with) it only takes 5 minutes of burning and he's got all the hot water he needs. The coil is situated in the right spot for that.

I believe that, I'm just not sure I care to wake up and go downstairs in the summer when the air conditioning is on and start a fire just to take a shower. It's not 1850 any more. $20/month to prevent me from having to burn wood in the summer doesn't bother me. Obviously this is subject to change :)

ac
 
Hmm...I am intrigued. You heat ALL of that with a 100? How often are you re-loading?

How does your non-heating DHW work for you? I am hesitant to use the WG for DHW when I'm not heating as I have heard it throws off a lot of heat.

ac
That depends on what the temperature is outside. The 100 actually throws a lot more heat than what it is rated for. When I talked with the people at AHS they said that eventually they would be discontinueing the E140 because it turned out to be to big for most peoples homes. That the E100 would push out something higher than 120-130 thousand BTU. Of course that depends on a lot of factors. If you have a good bed of coals for good gassification, what kind of wood, etc. etc. etc. When it was at it's coldest last winter, which was not very cold, I could go for over 10 hours until reload time. My 400 gallon buffer tank really adds to the system. That can buy me another 1-2 hours when good and hot.

Now I have to remind people. My boiler is in my basement. It radiates off so much heat that the call for heat never comes from the basement. Now you can subtract 825 feet off from the 4000+ sq.ft. The garage has it's own thermostat and has radiant heat in the slab and is insulated with spray foam in the walls and ceiling. That is kept at 45 degrees in the winter. So there is not much demand there. The laundry, office, and spare bedrooms and bath above the garage are kept at about 65. The other 2400 sq. ft. or so is kept about 70. This boiler is plenty capable of heating this house. The oil boiler for this house was sized at 129000 BTU. Partly because I told the furnace man that I would be improving the insulation to the house over the next few years. Which I did. Each time I do a remodel, I greatly improve the insulation in that area. The E100 seems to be able to keep up no problem.

The wood gun does throw off a lot of heat. I have mine in the basement and there is a window in the boiler room. When it is warm out, I put a fan in the window and blow the heat outside. Just opening another window in the basement creates a good breeze with the fan. I heat my tank up at night before I go to bed, then the hot water is ready in the morning. My buffer tank is fairly well insulated.
 
That's impressive. That's a lot of house for the 100 to keep up with so well.

I spoke to the guys at AHS (Ben) and he said I would need the 180 for my 2500 sq ft 1st floor ranch with vaulted ceilings + 1k sq ft basement (separate from the WG) + my 1500 sq ft well insulated work shop (separate building). I told him I wanted 12 hour burn capability in Northern NJ.

Throwing that excess heat is what has me hesitant to heat DHW with the WG in the spring/summer. I don't want to be warming an area I am also paying to try to cool in the spirit of saving money.

How is your buffer tank setup? Are there pics on the forum somewhere?

ac
 
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