Heatmaster G200 vs Garn

surefire

Member
Nov 15, 2014
47
Saskatchewan
I discovered the GARN four years ago and have been excitedly planning and prepping the installation ever since. But yesterday I discovered the Heatmaster G200, thanks to "3fordasho," "hondaracer2oo4" and "Karl_northwind,"
on the post "Heatmaster G200 + 550 gallons storage."

I like the Garn for its ability to eat (dimensionally) huge wood, its high efficiency (gasification), its simplicity, its integral storage, and its horizontal exhaust (way cool!) What I didn't like was its maintenance costs, namely, the annual chemicals to treat such a huge amount of water in an open system; the lower temp water which was going to require a huge WAHX; the cost, especially to bring it into Canada (plus parts and chemicals, as above); and the lack of activity on Youtube - it's been nearly two years since the GARN folks posted their latest video (April 2016). Plus there's that whole fiasco with the anode rods which I feel has only sort of been dealt with (and the solution not really proven). And if Switzer can make a pressurized boiler, why can't Garn?

I'm super excited about this Heatmaster G200! Looks like it can take my 24" wood (is this true?) of which I have cut, split, stacked, and seasoned ~20 cords. It can run without external storage so I can get up and running quickly (but I do want storage later). It runs best at high water temps so that will be great for a furnace/WAHX retrofit and DHW. It takes minimal tube cleaning what with that hand-cranked turbulator-shaker. It can be legally installed indoors (which it most definitely will be!) It can be loaded without smoke in the face just like the Garn. It's efficient like a Garn (I haven't compared the EPA stats though, and wonder if they factored in the clamped-down times or whether the test was full-tilt like with the Garn. Either way, with external storage I'm sure it could be made to be as efficient as a Garn). It is open, but I'd only be treating 200 gallons of water. It's stainless instead of mild steel. And, it's built in my own country, so no cross-border (and depreciated Canadian dollar) hassle. Oh yeah, and it's half the price.

Comments?
 
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goosegunner

Minister of Fire
Oct 15, 2009
1,469
WI
I would be very skeptical of the minimal cleaning of the tubes. I would want to see how easy it is to access the fire tubes and how involved it is to clean them. If its not very simple I would look elsewhere. I have had 2 indoor boilers. Econoburn which was a pain in the butt to clean I dreaded it. Now the Froling which is so simple to clean its no big deal.
 
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3fordasho

Minister of Fire
Jul 20, 2007
992
South Central Minnesota
I discovered the GARN four years ago and have been excitedly planning and prepping the installation ever since. But yesterday I discovered the Heatmaster G200, thanks to "hondaracer2oo4" and "Karl_northwind,"
on the post "Heatmaster G200 + 550 gallons storage."

I like the Garn for its ability to eat (dimensionally) huge wood, its high efficiency (gasification), its simplicity, its integral storage, and its horizontal exhaust (way cool!) What I didn't like was its maintenance costs, namely, the annual chemicals to treat such a huge amount of water in an open system; the lower temp water which was going to require a huge WAHX; the cost, especially to bring it into Canada (plus parts and chemicals, as above); and the lack of activity on Youtube - it's been nearly two years since the GARN folks posted their latest video (April 2016). Plus there's that whole fiasco with the anode rods which I feel has only sort of been dealt with (and the solution not really proven). And if Switzer can make a pressurized boiler, why can't Garn?

I'm super excited about this Heatmaster G200! Looks like it can take my 24" wood (is this true?) of which I have cut, split, stacked, and seasoned ~20 cords. It can run without external storage so I can get up and running quickly (but I do want storage later). It runs best at high water temps so that will be great for a furnace/WAHX retrofit and DHW. It takes minimal tube cleaning what with that hand-cranked turbulator-shaker. It can be legally installed indoors (which it most definitely will be!) It can be loaded without smoke in the face just like the Garn. It's efficient like a Garn (I haven't compared the EPA stats though, and wonder if they factored in the clamped-down times or whether the test was full-tilt like with the Garn. Either way, with external storage I'm sure it could be made to be as efficient as a Garn). It is open, but I'd only be treating 200 gallons of water. It's stainless instead of mild steel. And, it's built in my own country, so no cross-border (and depreciated Canadian dollar) hassle. Oh yeah, and it's half the price.

Comments?

The G200 has been around maybe 5 years, while garn has 30 year old units still in service so there is that. Otherwise you've pretty much hit all the reasons I'm doing the same comparison. Garn is 90minutes from me and I can go get it with my own truck and trailer. For me the Garn is more expensive but not double. I spent a hour on the phone with Garn just this week, good conversation and lots of good info. For pricing I had to call the local rep, he kind of implied that all communication should be though him even though Garn said it was fine to call direct for tech questions.
Then the rep pretty much insisted the I need the 1500 vs the 1000 gallon and even with the 1500 I would need to fire it every 8hrs during our coldest weather. Something is way off there. Bottom line I'm in the same boat as you, thought I was sold on a Garn but now everything is back on the table. FWIW the Switzer boiler looks like the best bang for the buck for my location and application anyway.
 
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Buzz Saw

Minister of Fire
Jan 18, 2014
523
Attica, Ohio
As far as water treatment, once you have your water chemical levels in spec there is no additional chemical to buy. I had to spend $150 additional to get my water levels in check.

Also as long as you send the water sample every 6 months there is no charge for the lab analysis.

As far as WAHX I doubled my btu output to 150k to use the temps down to 120°F or so. My slabs will heat to 90°F water.

This is only my second season so I'm still tweaking as I go.

Sent from my SM-G950U using Tapatalk
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
24 inch wood is perfect. The firebox is 30 total so 24 fits great. As far as the tests, they performed 4 tests. I believe they were something in the range of 35k, 55k, 110k,210k btu. They test are performed with a constant load of the given load on the boiler with a full firebox load of 160 pounds of wood. The 35k load went for 26 hours I think? The 210k load went for 4 hours I believe? Here is the epa hydronic heater list which has the particulate output as well as the efficiencies. https://www.epa.gov/sites/production/files/2016-03/usepa_certified_hydronic_heaters_list.xlsx

As you can see the g200 and the Garn units are pretty much the same efficiency and emissions levels. Right about 75 percent efficient and very very clean at .07.

As far as fire tubes and maitenence. The tubes are accessible by the roof if something happens but I am on my third season and I have looked st the firetubes at the end of every season and they never have anything on them. The fly ash gets shaken off by the turb shakers and I have seen zero creosote past the firebox itself. From the nozzle on all you get is powder ash. I rake the powder out of the reaction chamber after each cord burned and get about 3 gallons of ash. I see no reason the tubes should ever get creosote on them.

If you have any questions I am happy to ask. The boiler is a very well built boiler with attention to detail.
 
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maple1

Minister of Fire
Sep 15, 2011
10,733
Nova Scotia
Even with only fly ash, it doesn't take much of a layer on tubes to affect efficiency somewhat

I don't have either, but I have a schedule of brushing my tubes every Sunday. Which takes 5 minutes.

Admittedly I have no experience with turb shakers so don't know how well they do or don't work. But I have a feeling they don't work as well as brushing? But having said all that, that effect on efficiency may or may not be enough of an effect to worry about.

If I was considering a Garn though, I would definitely also be considering a Switzer.
 

maple1

Minister of Fire
Sep 15, 2011
10,733
Nova Scotia
Then the rep pretty much insisted the I need the 1500 vs the 1000 gallon and even with the 1500 I would need to fire it every 8hrs during our coldest weather. Something is way off there.
Hmm, my thought too. I thought the Garn had a pretty big firebox - but how big is it? It all comes down to heat load of course, but I think my coldest days I burn around 10cu.ft./day, max.
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
Maple, I would agree that shaking vs brushing would not be the same at getting ash off but it seems from my expietence that very little ash makes it up the tubes since I only have to vacuum the ash out from above the tubes at the end of each season and there is a 1/4 to half inch of fine ash up there. I have a flue gauge on my flue and my temps are 300-320 normally when burning a mix f hard maple and oak. When I burn straight oak I see temps of 320-380. Max temp I have ever seen is 420 on a crazy hot cycle.
 

maple1

Minister of Fire
Sep 15, 2011
10,733
Nova Scotia
That throws me sideways into something about EPA testing I wondered about for a while. If a mod is made to catch ash before it hits the chimney (like by some kind of cyclonic action or a slow down in gas speed so ash can settle out), better testing results could be gotten because the particulates are left behind for cleaning out from the bottom and not necessarily because it's burning cleaner.

And conversely, I hear some say (not really pertaining to newer 'EPA' stuff) they have next to no ash to clean out so that means their burner is burning cleaner. But it might really mean most of the ash is going up & out the chimney & it isn't really burning cleaner.

Carry on.....
 
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hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
I kind of see where you are heading but not exactly. There is "inert" material that can not be consumed by any combustion process. That is what is being left over inside the stove. It is not particulates in te smoke due to an incomplete combustion process. I remove the ashes(powder) from the reaction chamber after each cord burned. I get about 3 gallons of ash left over after a cord, what else are you looking for complete combustion from turning 128 cubic feet stacked of cordwood into 3 gallons of powder?
 

goosegunner

Minister of Fire
Oct 15, 2009
1,469
WI
How does the Heatmaster handle idle situations? Does it completely shut air dampers? If you fill it full of wood it has to idle on and off right?
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
With the Heatmaster g series they are a negative draft system. So when there is a call for heat the draft fan kicks on and there is a Honeywell controller which opens a damper plate to provide air to the primary air and secondary nozzle. As the boiler gets closer to 180 degrees it starts to close damper down so that it doesn't overshoot 180. When the boiler reaches 180 the damper plate completely closes off any air.
 

surefire

Member
Nov 15, 2014
47
Saskatchewan
Thanks everyone for your input.

Water treatment: there was a post a while back from Woodfarmer1 stating that it was costing him $200 a year for chemicals for his Jr. Which would be double that for a WHS2000. I think I'll start another thread to ask Garn owners how much they're having to spend on chemicals each year.

The Garn does have over thirty years of experience, but less than five running without sacrificial anode rods, so that issue resets the clock in my books.

Buzz Saw, thanks for the info on WAHX sizing. Good to know you can use water down to 120 with it. You chose a 150k - what is your design day load? Also, what made you go with the garn in the end? I can see by some old posts that you were unsure at times about a future garn purchase.

Honda, glad to hear that my 24" wood will work. I found the full EPA report, and I see that they used 24" wood during the test. It was also interesting to see that at 32k the efficiency was the same as burning full out! (74.4%) That is encouraging with regards to shoulder season burning.
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
Yes the numbers are quite good for
The g200. Heatmaster really hit the nail on the head with te design.
 

3fordasho

Minister of Fire
Jul 20, 2007
992
South Central Minnesota
Hmm, my thought too. I thought the Garn had a pretty big firebox - but how big is it? It all comes down to heat load of course, but I think my coldest days I burn around 10cu.ft./day, max.
14.7 cu.ft. firebox for the 1000, 17.4 cu.ft. for the 1500/2000. I burn 10.5 cu.ft. per day for the House, 3.5 cu.ft. per day in the shop to keep it above freezing. The Garn sizing calculator says this load would require firing every 11hrs for the 1000, 20hrs for the 2000. They don't have the 1500 in the sizing calculator for some reason. So firing the 1500 every 8hrs @ 17.4 cu.ft. firebox seems way off. Obviously warming up the shop and keeping it there will change thing but I'm only doing that when I'm around to stoke the fire as necessary - I only use the shop a evening or two a week and some weekends.
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
Everyone's heat loads are different. I am heating 2800 ft.² of 220-year-old house decently insulated. This year with what I have gone through so far in wood divided by the number of days loading two times per day I am at just over 2.5 ft.³ per 12 hours.
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
The heatmaster g series damper actuator is a spring return actuator. When the actuator is depowered the spring return closes the damper. This is how it operates at the end of every cycle. When the boiler reaches 180the actuator is depowered and the spring returns the damper to the fully closed position.
 

S.Whiplash

Member
Oct 28, 2012
110
The size of the firebox has very little to do with how often you would have to re-fire a Garn, it is more dependent on the volume of stored energy contained and how quickly it is depleted. The larger the heat-load and the higher the demand temp. the quicker the stored BTU's will be consumed, it's all math.
Energy Stored (120 F to 195 F)
WHS-1000 649,100 BTUs
WHS-1500 892,300 BTUs
WHS-2000 1,196,900 BTUs

One thing that sets Garn apart from other high-efficiency wood boilers is that they only run 5-6 hours a day, so over the long-term there is a lot less wear and tear on components, hence they tend to last a long time.
 

maple1

Minister of Fire
Sep 15, 2011
10,733
Nova Scotia
The size of the firebox has very little to do with how often you would have to re-fire a Garn, it is more dependent on the volume of stored energy contained and how quickly it is depleted. The larger the heat-load and the higher the demand temp. the quicker the stored BTU's will be consumed, it's all math.
Energy Stored (120 F to 195 F)
WHS-1000 649,100 BTUs
WHS-1500 892,300 BTUs
WHS-2000 1,196,900 BTUs

One thing that sets Garn apart from other high-efficiency wood boilers is that they only run 5-6 hours a day, so over the long-term there is a lot less wear and tear on components, hence they tend to last a long time.
Yes but stored energy is also stored in the wood. So the more wood the firebox can hold, the less often you would need to re-fire. Or perhaps, maybe there is a bit of cross talk between re-fire, and re-load - bigger firebox means less re-loading. I kind of think of them as meaning the same thing, but they likely don't to others.

The 5-6 hours a day isn't just a Garn thing, it applies to any efficient wood boiler that is tied to or incorporates storage. I usually average maybe 6 hours a day over the winter - think I am at less than that this winter, usually 5.

Not to sidetrack, but is there a reason that you're not considering or comparing pressurized boilers also? (That was for the OP).
 
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hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
Just a point to ponder on the less wear and tear on the garn only running 5-6 hours per day. My g200 averages 30-40 min cycles. I have a data logger so i record all the cycles and see how many times per day it cycles depending on outside temp and how long the cycles last. I have only seen 11 cycles in a 24 hour period during -15 nights with 0 degree days. Right now with temps in the 30s I am doing 8 cycles per day. At a average of 35 mins that means that I am only running about 4 hours and 40 mins. So that means that I have the same run times that a garn does, no difference in wear.
 

hondaracer2oo4

Feeling the Heat
Jan 18, 2012
414
Canterbury NH
It is a lascar WiFi temp probe. It is cloud based so you can view the historical chart and data from anywhere. They also have a phone app. If you just google lascar WiFi tp you will find the model I have. They are around $130. Super easy to set up and use. Here is a picture of the graph zoomed down to a few hours. I have it strapped to my return line after my flat plate. So you can see every time the graph takes a small dip down my house is calling for heat. You can see how long it takes to cycle from 160-180(the temp probe is zip tied to the return line, I don’t have a thermo well on the return so it reads 4 degrees lower than actual temp) and you can see how long it takes to go from 180-160.
 

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surefire

Member
Nov 15, 2014
47
Saskatchewan
Not to sidetrack, but is there a reason that you're not considering or comparing pressurized boilers also? (That was for the OP).
Well, I've been cutting 24" long firewood for about 24 years, so as absurd as it seems, it is my first question in the selection process. I'm used to being able to burn big wood, and although I do have a splitter, I don't want to turn everything into kindling just to burn it. So, I haven't come across any pressurized gassers that can burn larger wood like that. Except for the Switzer I guess, but its design does not attract me.

I would prefer pressurized, as I mentioned in my opening post. The Heatmaster would allow me to limit my unpressurized side to an easier-to-treat 200 gallons, and then I'd make the rest of the storage pressurized.