Heatmaster G200 + 550 gallons storage

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

3fordasho

Minister of Fire
Jul 20, 2007
1,038
South Central Minnesota
Anyone added storage to the Heatmaster G series? I see they can be installed in a shop or other out building. I have a nice 550 gallon Stainless square tank, any reason this should not be tied in as open storage?
 
I don't see any reason not to. I have a g200. I am on my third season. It is a workhorse. I went from burning 12-13 cords per year down to 6 3/4-7 cords per year. Since you wouldn't be doing batch burning, just drawing out the cycles to about 2.25 times longer than a normal cycle with the g200 with 200 gallons I would say that you may gain a slight efficiency because of the less start ups and shut downs but you will probably need to increase your purge cycles to more often to keep the coal bed alive during the long idle times.
 
I don't see any reason not to. I have a g200. I am on my third season. It is a workhorse. I went from burning 12-13 cords per year down to 6 3/4-7 cords per year. Since you wouldn't be doing batch burning, just drawing out the cycles to about 2.25 times longer than a normal cycle with the g200 with 200 gallons I would say that you may gain a slight efficiency because of the less start ups and shut downs but you will probably need to increase your purge cycles to more often to keep the coal bed alive during the long idle times.

Thanks for the reply. I'm in the middle of central boiler country and as such Heatmaster is well represented with a stocking dealer about 30mn away. I'm pretty much sold on the batch burn to storage camp and was wondering since the G200 is basically a down draft gasser/tube exchanger design with extra water storage on board, if it would work in a batch burn mode. With the G200's onboard~200 gallons + additional 550gallon I could potentially get by with one burn a day depending on conditions.

I would have to weigh wood loads depending on storage temps but even if overloaded it seems the G200 seems to have a pretty good handle on the idle mode.

How does Heatmaster handle return temp protection?

What do they recommend for water treatment?

Appreciate your comments, I know the dealer is a resource but I really don't want to get them into "sales" mode until I've narrowed the field a bit.
 
The g series has a shunt pump on the boiler dedicated to water jacket mixing. They used to just spec that you had to flow 16 gpm minimum for water jacket flow and then decided to move to a dedicated shunt pump. They do not require a return protection valve but as we all know you should keep your return temps above 140.

They provide free water testing and you need to send in one annually to keep your warranty. They use “certified labs” brand water treatment which is what they base their suggestion on how much treatment to add to get into the ranges they want.

You could do one hell of a batch burn if you had a big enough water store. My average by the numbers so far this year has been 2.5 cubic feet per 12 hour loading. I am heating 2800 sqft 220 year old house in New England. I just passed 3.3 cords burned since October 28.
 
You would get the most efficiency returns, by batch burning. That would mean you would have to make a new fire every day, but I got over that 'hardship' pretty quick. The catch there is that your HX setup, to get the heat into storage (since you mentioned open storage), would need to be capable of moving full boiler BTU output into storage, or else you're still going to get into some idling.

The one thing I would be wary of has already been touched on. Depleted storage is usually capable of returning much colder water back to the boiler for longer times than almost any heating system would - except for radiant floor. But that would usually have a flat plate HX in between. So I would check or ask that the shunt setup can handle long periods of relatively cold return water, for boiler protection.

Is the G200 open or pressurized? (Excuse my ignorance on that...)
 
It is an open system. If you did a full batch burn system with an all out charge until wood load depleted system then you would be running like any indoor gasser system as far as return temps, no? System would slowly cool off until you needed to fire again. The firebox is 15 cuft. You could really get a large water store charged up with one loading. I would think if you were going to go the direction of batch burning then I would go all out and do a 1000 gallon plus size. I am not that familiar with batch burning though so maybe I am wrong.
 
It is an open system. If you did a full batch burn system with an all out charge until wood load depleted system then you would be running like any indoor gasser system as far as return temps, no? System would slowly cool off until you needed to fire again. The firebox is 15 cuft. You could really get a large water store charged up with one loading. I would think if you were going to go the direction of batch burning then I would go all out and do a 1000 gallon plus size. I am not that familiar with batch burning though so maybe I am wrong.

Yes, that's correct. But there are two important things - you need to maintain 140+ return, and you need to be able to move enough heat out of the boiler when it is at full burn to avoid idling.

The first thing is tricky because depleted storage can send colder water back for longer periods of time. Which usually means a boiler protection mixing setup. But if the boiler is open (therefore would have an HX in between), plus already has a shunt setup as a form of boiler protection, it should be OK. But you would want to watch for it.

The second might be trickier, as I am thinking the G200 can pump out a lot of heat when it is at full burn. So you would need pretty capable heat exchanger to move the heat to storage. Or it would still do some idling. It would be reduced idling, but still likely some.

Yes, IMO more storage is better. That would also mean though that the boiler would be sitting a bit longer in between burns, with no fire in it. Which may or may not be a concern with an OWB (freezing etc.) - shouldn't be though if the boiler is in a shop or outbuilding.

I have maybe 700 gallons between my storage & boiler. I do one burn a day, usually for 6 hours or so except for the coldest of days here. Yesterday it was only 4-5 hours.
 
The owb gassers have to pass an epa test. they make 4 runs with 4 different btu draws. I think the rates that they ran the g200 was 32k , 55k, 120k, 210k. On the 210k btu load they depleted a full firebox with 160 pounds of wood in 4 hours. You would probably need a 100 plate hx on the storage.
 
The owb gassers have to pass an epa test. they make 4 runs with 4 different btu draws. I think the rates that they ran the g200 was 32k , 55k, 120k, 210k. On the 210k btu load they depleted a full firebox with 160 pounds of wood in 4 hours. You would probably need a 100 plate hx on the storage.

I was thinking no HX between boiler and storage, both open. A HX between boiler/storage and house / shop loops. And then just wait for the idiots at work to vacuum collapse another stainless liquid tote = 550 gallons more storage :)
 
Don't you mean helpers? [emoji6][emoji1]

Sent from my SM-G950U using Tapatalk

Yes, that's it, helpers. ;)

Unfortunately part of my job is making equipment idiot proof and the auto vents I added to those totes seem to be working...

The guy that forgot to open the manual vent on top of the tote almost lost his job over it. His coworkers watched in amazement as that 4' square x 6' tall stainless container collapsed like a pop can as the positive displacement pump sucked product out of it.
 
  • Like
Reactions: Buzz Saw
you should be OK to do that with no problem. I'd just use an aquastat or a taco Viridian circulator to keep the return temperatures protected until the unit is up to temperature (170 or so water temp. that'll keep the modulation at 100%). I'd ask the factory where they think the best place to watch the temps would be. the G200 would raise that 700 gallons of water 60 degrees F in a couple hours at full burn (figuring 120 start and 180F end). if you let the refractories and such cool down and let the coal bed go out, when you re-light the boiler at 120F it will take a little while to get up to temperature and clean up the burn.
It does really well when everything's hot, but it's not really designed as a batch burner.

you can really pack a lot of wood in there when it's 24" long and 3-6" rounds. I can go 24 hours on my drafty 1400 SF stone barn at -10F if I load it right. most of the time I'm burning stove length (16-18" long splits) and so can't load nearly as much in there.

karl
 
Hmm. I thought I posted this last night.
I think you'd be OK with the g-200 burning like that. but know that if you have to start it at 120F (minimum useable temp?) you will be a while till you get it up to proper temp to clean up the burn really well. it's meant to stay hot, and runs well that way. 550 gallons plus the G-200 will only take about 2 hours to charge once the burner is rolling at full output. you will need more expansion I think than is built in to the water jacket of the G-200. the tank you have will work well though because it's well below the height of the top of the G-200.

depending on your heat load, I'd seriously think about a G-100, as that's better suited to that size storage, and a couple loads a day could handle most residential heating loads, with the bonus ability to Idle well if you need to, as well as taking much less footprint than the G-200.

I'm heating a 1400 SF stone barn with my G-200. it's pretty leaky but at sub zero temps I can heat it for 24 hours with a ~250? Lb load of 20% MC wood. 3-6" rounds. oak and ash. I'm going to have to weigh a wood load one of these days and analyze the boiler output.
 
Hmm. I thought I posted this last night.
I think you'd be OK with the g-200 burning like that. but know that if you have to start it at 120F (minimum useable temp?) you will be a while till you get it up to proper temp to clean up the burn really well. it's meant to stay hot, and runs well that way. 550 gallons plus the G-200 will only take about 2 hours to charge once the burner is rolling at full output. you will need more expansion I think than is built in to the water jacket of the G-200. the tank you have will work well though because it's well below the height of the top of the G-200.

depending on your heat load, I'd seriously think about a G-100, as that's better suited to that size storage, and a couple loads a day could handle most residential heating loads, with the bonus ability to Idle well if you need to, as well as taking much less footprint than the G-200.

I'm heating a 1400 SF stone barn with my G-200. it's pretty leaky but at sub zero temps I can heat it for 24 hours with a ~250? Lb load of 20% MC wood. 3-6" rounds. oak and ash. I'm going to have to weigh a wood load one of these days and analyze the boiler output.


Hi Karl,
Appreciate the feedback, I've been looking at the Garn or Switzer boilers in the 1000 gallon sizes, but the Heatmaster sparked my attention as it can be installed inside a shop or garage - though I've not heard of many installed this way. I would not consider installing something outside in the elements - I have a 24'x24' garage available for boiler/wood storage use that is located in between the heated structures.

The Heatmaster would probably be able to be sold if I ever move or get too old to do the wood thing. The other two not as likely at least to the farmers around here. Yes I could just leave it behind, but finding a new owner that the wood set up actually has value to is not too likely these days.

I plan to heat a 3400 sq ft house that requires about 200 gallons/month of propane in the coldest months, and a 2400 sq ft Quonset style shop. The shop is spray foamed but the slab is not insulated - currently it takes about 75lbs of wood a day to keep it above freezing, and 3 times that + a little propane when I want to warm it up to work on projects.

I would like to size the system for 1 load a day. More than that would be acceptable on days I want to keep the shop warmer than 40F.

As far as storage sizing, not limited to the 550 gallon tank- I just happen to have one that was basically "free".
 
A simple way to address the boiler protection is with a near boiler pump.My Econoburn has this as a recommended option if hooked to storage.
Basically you have one pump that is right at the boiler running off an aquastat,which circulates water in the boiler till it reaches a set temp.Then the main pump takes over and sends the BTU's to storage.If the temp drops to low the near pump starts again till the temps come up.You can set the temps for the pump to run and shut off.
 
The g series comes with a shunt pump. If you simply strapped an aquastat to the outgoing line to your load thst would only allow the main pump to run if the boiler was above a certain temp.
 
  • Like
Reactions: Karl_northwind
Hi Karl,
Appreciate the feedback, I've been looking at the Garn or Switzer boilers in the 1000 gallon sizes, but the Heatmaster sparked my attention as it can be installed inside a shop or garage - though I've not heard of many installed this way. I would not consider installing something outside in the elements - I have a 24'x24' garage available for boiler/wood storage use that is located in between the heated structures.

The Heatmaster would probably be able to be sold if I ever move or get too old to do the wood thing. The other two not as likely at least to the farmers around here. Yes I could just leave it behind, but finding a new owner that the wood set up actually has value to is not too likely these days.

I plan to heat a 3400 sq ft house that requires about 200 gallons/month of propane in the coldest months, and a 2400 sq ft Quonset style shop. The shop is spray foamed but the slab is not insulated - currently it takes about 75lbs of wood a day to keep it above freezing, and 3 times that + a little propane when I want to warm it up to work on projects.

I would like to size the system for 1 load a day. More than that would be acceptable on days I want to keep the shop warmer than 40F.

As far as storage sizing, not limited to the 550 gallon tank- I just happen to have one that was basically "free".

The house requires about 30,000 BTU per hour in the coldest months then, must be pretty new and or pretty tight for 3400 SF. I would figure about 50,000 for a shop like that. so you are in the 80,000 btu at the coldest time. you could do 24 hours reasonably well with a G-200 most of the heating season, if you kept the shop at 40F, and only bumped it up to work in there, you'd add a load a day. YMMV, I'm doing this sight unseen, of course.

The garn and switzer are good units, but the ability to provide 170-180F water all the time makes working with a G-series nice to work with from a design and installation standpoint.
 
The house requires about 30,000 BTU per hour in the coldest months then, must be pretty new and or pretty tight for 3400 SF. I would figure about 50,000 for a shop like that. so you are in the 80,000 btu at the coldest time. you could do 24 hours reasonably well with a G-200 most of the heating season, if you kept the shop at 40F, and only bumped it up to work in there, you'd add a load a day. YMMV, I'm doing this sight unseen, of course.

The garn and switzer are good units, but the ability to provide 170-180F water all the time makes working with a G-series nice to work with from a design and installation standpoint.

Higher available water temp is certainly a plus, I've spent some effort in determining what kind of emitters will work in a retrofit situation with out gutting the house (not happening). So there are some places where radiant wall could be installed, but the bulk of the work will have to be from a water to air HX above the A/C coil in the existing FA furnace. I assume the water/air HX is pretty common with G200 installs? For some reason GARN warns against it on a condensing gas furnace.... aren't they all condensing gas furnaces now? Can't even install a 80% furnace around here.

The house is a 1982 build with very good insulation considering the era. 2x6 walls spray foamed, generous cellulose in ceiling, foam on foundation walls. Door and window seals needed help but I've replaced the window seals and replaced the doors.
 
Higher available water temp is certainly a plus, I've spent some effort in determining what kind of emitters will work in a retrofit situation with out gutting the house (not happening). So there are some places where radiant wall could be installed, but the bulk of the work will have to be from a water to air HX above the A/C coil in the existing FA furnace. I assume the water/air HX is pretty common with G200 installs? For some reason GARN warns against it on a condensing gas furnace.... aren't they all condensing gas furnaces now? Can't even install a 80% furnace around here.

The house is a 1982 build with very good insulation considering the era. 2x6 walls spray foamed, generous cellulose in ceiling, foam on foundation walls. Door and window seals needed help but I've replaced the window seals and replaced the doors.
I'm a huge fan of panel radiators. you can do room by room zoning, still have your coil above the A coil in the furnace for whatever you need. you can run them with 1/2 or even 3/8" pex, and snake it thru all sorts of places. I don't remember garn's reasoning against the condensing furnace.
 
For some reason GARN warns against it on a condensing gas furnace.... aren't they all condensing gas furnaces now? Can't even install a 80% furnace around here.

FWIW I ignored that suggestion from GARN when I did my install . I figured everyone else was doing it with great success, so why not a GARN. Heck most of the time the GARN water runs cooler than a OWB.

Another FWIW the HeatMaster was on my short list behind the GARN. If I would of gone that route it was going to be installed in my garage/ workshop. Ultimanty I choose the GARN because I didn't want smoke filling my shop during a reload. I don't know how much would spill out but a little was more than I wanted.

Sent from my SM-G950U using Tapatalk
 
The g200 does very well with no sMoke with the bypass and negative pressure fan.
 
If you open the load during a burn, it will smoke a bit. if you don't fiddle with it and you have figured out how long you can go between loads given your heat load, and load it after it's let the water temp run down to 170 or lower after shutdown it'll be minimal smoke.
 
I've heard that you can't have a heating WAHX with an A/C coil in the same plenum. Is this true?

Not sure about the a/c coil and WAHX combo but the outside boiler guys seem to do it all the time. Never on the return air side and above the a/c coil on up flow set ups.

Garn recommends against installing a WAHX in the condensing furnaces (90%+ efficient) for a couple reasons, first it will void the warranty on the condensing furnace, second some of these furnaces are sensitive to air flow thru the furnace, especially with some of the china manufactured WAHX that are manufactured with fin spacing that is too restrictive. Bottom line, you may need to bump up blower speed or go to a bigger blower motor in some cases.

I think it's all about restricting the air path too much, take a condensing furnace with its primary HX and secondary HX, then add a/c coil, then add WAHX, filter on the return side - lots of stuff to blow or suck air through.
 
  • Like
Reactions: sloeffle
Maybe answering my own question: just reading the Heatmaster manual which says that "the exchanger should be mounted below the A/C coil if possible." Edit: 3fordasho, didn't see your reply before I posted! Thanks.