DS Machine Comfortmax 75 Update (on Wood)
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
Since its finally become winter here, we've finally gotten around to firing up the ComfortMax for a test run. Presently burning Enviro-Bricks (highly compressed sawdust blocks that each weigh 3.5 lbs.) in the ComfortMax. It's around 3 to 4 degrees F. outside right now, and a comfy 77 degrees in our living room (where the stove is). 70 degrees in a bedroom down the hall. No fans running , and no blower on the stove. Getting a decent (for wood) 5 to 5.5 hours between feedings, which are only 4 Enviro-Bricks per. Still have not tried coal in it. (First loading of wood bricks only lasted a bit more than 3 hours, but subsequent loads are going 5 to 5.5 hours)
Most claims are for 8,000 BTU's per pound for this type of high pressure compressed sawdust blocks, but I'll assume 7,500.
7,500 BTU's/LB. x 3.5 lbs/brick = 26,250 BTU's per brick
4 bricks x 26,250 BTU's = 105,000 BTU's per stove feeding
105,000 BTU's x ~0.70 = 73,500 output BTU's (allowing for 70% efficiency)
73,500 BTU's of total output/ ~5.25 hours between loads = ~14,000 BTUH output
14,000 BTUH seems to be all it takes to heat our entire upstairs at roughly 3 to 4 degrees outside. The coal boiler is still heating the downstairs (finished walk-out basement and garage) and our DHW. We will probably only continue this experiment through this weekend. It supposed to get to a high of 10 degrees here today, and a low of -1 tonight.
Most claims are for 8,000 BTU's per pound for this type of high pressure compressed sawdust blocks, but I'll assume 7,500.
7,500 BTU's/LB. x 3.5 lbs/brick = 26,250 BTU's per brick
4 bricks x 26,250 BTU's = 105,000 BTU's per stove feeding
105,000 BTU's x ~0.70 = 73,500 output BTU's (allowing for 70% efficiency)
73,500 BTU's of total output/ ~5.25 hours between loads = ~14,000 BTUH output
14,000 BTUH seems to be all it takes to heat our entire upstairs at roughly 3 to 4 degrees outside. The coal boiler is still heating the downstairs (finished walk-out basement and garage) and our DHW. We will probably only continue this experiment through this weekend. It supposed to get to a high of 10 degrees here today, and a low of -1 tonight.
Heating options are good to have. If something mechanical on the boiler would crap out at 3am tonight when it's -1 out it's a good feeling to know you are not in emergency mode scrambling to keep the pipes from freezing!
But......WHERE ARE THE PICTURES?!?!?!?!?!?
I mean those numbers are all fascinating and interesting and real scientific and thought provoking and all that.... but what about those of us that just look at magazines for the pictures and not the articles?!?!
A nice mid burn pic would have us feeling all warm and fuzzy inside!
But......WHERE ARE THE PICTURES?!?!?!?!?!?
I mean those numbers are all fascinating and interesting and real scientific and thought provoking and all that.... but what about those of us that just look at magazines for the pictures and not the articles?!?!
A nice mid burn pic would have us feeling all warm and fuzzy inside!
- Keepaeyeonit
- Member
- Posts: 1681
- Joined: Wed. Mar. 24, 2010 7:18 pm
- Location: Northeast Ohio.( Grand river wine country )
- Baseburners & Antiques: Glenwood #8
- Coal Size/Type: Nut & stove
- Other Heating: 49 year old oil furnace, and finally a new heat pump
Dam Larry I forgot you bought a stove, well when do you plan on feeding that beast coal? I would think you could do that 14,000 BTU/ hr on 1.6 lbs of coal/ hr right?( I would think thats $4.85/ day on coal )what Is the cost difference from the bricks to coal? I do know the coal will require less tending though,
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
Here is the picture I just took. The flash wiped out any view of the fire, but the temperature gauges are visible for an indicator of the heat. The stack gauge is probing internal, and not merely a magnet measuring the surface. Enviro-Bricks are just visible to the lower left of the stove. Pay no attention to the sawdust. Yelling at me for that will be my wife's job. I'd better get the broom and go at it. After only one day of burning wood the glass is about 2/3 yucked up already. Must be making plenty of creosote.
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
My wife is not keen to coal. I haven't been able to sell her on that for her living room yet. I got 2 tons of the compressed sawdust bricks on sale for $175/ton after tax (our pick up). Coal has been costing me about $270/ton after tax (delivered).Keepaeyeonit wrote:Dam Larry I forgot you bought a stove, well when do you plan on feeding that beast coal? I would think you could do that 14,000 BTU/ hr on 1.6 lbs of coal/ hr right?( I would think thats $4.85/ day on coal )what Is the cost difference from the bricks to coal? I do know the coal will require less tending though,
Yes, about 1 x 40 lb. bag of coal per day should do it.
:punk: Nice looking set up!! The hearth pad and brickwork look good. Did it smoke off much in the first burn?
Just keep leaving that sawdust laying around, mention how hard sawdust is to control and that coal has none of that and she'll come around!
Just keep leaving that sawdust laying around, mention how hard sawdust is to control and that coal has none of that and she'll come around!
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
Yes, the house smelled of oily burnt paint yesterday.titleist1 wrote::punk: Nice looking set up!! The hearth pad and brickwork look good. Did it smoke off much in the first burn?
Just keep leaving that sawdust laying around, mention how hard sawdust is to control and that coal has none of that and she'll come around!
- Keepaeyeonit
- Member
- Posts: 1681
- Joined: Wed. Mar. 24, 2010 7:18 pm
- Location: Northeast Ohio.( Grand river wine country )
- Baseburners & Antiques: Glenwood #8
- Coal Size/Type: Nut & stove
- Other Heating: 49 year old oil furnace, and finally a new heat pump
Nice looking setup except the saw dust , so the blocks are around $.75/day more, easier to start and let burn out but more tending( I'm sure you could go a full 24 hrs with that amount of coal though), I guess Its a good trade off for only a backup,to take the chill off, or an emergency. If your not going to run It very often then that may be your better choice.
- warminmn
- Member
- Posts: 8189
- Joined: Tue. Feb. 08, 2011 5:59 pm
- Location: Land of 11,842 lakes
- Hand Fed Coal Stove: Chubby Junior, Riteway 37
- Coal Size/Type: nut and stove anthracite, lignite
- Other Heating: Wood and wear a wool shirt
Looks nice! My Dad likes burning those bricks too, and you can fit a few hundred pounds of them in a very small area. No mess either. Not as cheap as coal but perfect for what you want them for.
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
I just loaded the coal boiler and added 43 less pounds than my computer program calculated.
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
The biggest drawback I've seen for the ComfortMax in very limited firing is that (as for all EPA stoves) it is limited in the degree to which you can throttle it down. It burns hot by design to meet the EPA regs. Great when it reaches -7 outside, but not likely so great at other times. The sawdust blocks I was burning compound this problem by also inherently burning hot (due to only 8% moisture). I have even heard rumors that at least one major stove company has declared the sawdust blocks off limits in their EPA stoves and stated that using them voids the warranty.
Perhaps anthracite pea can mitigate this?
Perhaps anthracite pea can mitigate this?
- lsayre
- Member
- Posts: 21781
- Joined: Wed. Nov. 23, 2005 9:17 pm
- Location: Ohio
- Stoker Coal Boiler: AHS S130 Coal Gun
- Coal Size/Type: Lehigh Anthracite Pea
- Other Heating: Resistance Boiler (13.5 KW), ComfortMax 75
no problem, only a match for wood burned.blrman07 wrote:And this is a problem why?lsayre wrote:I just loaded the coal boiler and added 43 less pounds than my computer program calculated.
- Keepaeyeonit
- Member
- Posts: 1681
- Joined: Wed. Mar. 24, 2010 7:18 pm
- Location: Northeast Ohio.( Grand river wine country )
- Baseburners & Antiques: Glenwood #8
- Coal Size/Type: Nut & stove
- Other Heating: 49 year old oil furnace, and finally a new heat pump
Anymore updates on the ComfortMax Larry?