Surdiac Hopper Fed Coal Stove

I solved the problem of burn in the hopper by installing a new gasket on the glass door ! Air leaking in the glass door is a disaster to trying to get a good burn in a coal stove.

elleninpa wrote:an update on our old surdiac...dh says with the new gasketing and the new grates that we are getting longer burn times, might also be the red ash coal we've been using too, and I don't notice the coal smell as strongly outside either, all good things.

Perhaps my sense of smell isn't so good anymore after working 30 years in the chemical industry but in 10 years of running a 715 I never noticed much of a smell outside. Usually, all I could smell was the neighbor's wood stove. Our chimney was about 30 feet up.

I like the 715. My father in law has one. The big top door is nice as well as longer burning times for wood! Mine's a 513. I need new glass for the front door. I'm gonna try to replace it with a one piece instead of many 7/8" by 7 1/8" little pieces.

elleninpa wrote:try to get a bag of better quality anthracite and see how that goes...clinkers is a term initially used for bituminous, and they do form with the impurities in coal (silicas whatnot).

other thoughts: cleaning out the compartments behind the stove? that fine coal ash gets everywhere! even in the back corners of the grates and under the ash pan we have to clean out when we shake down (poke down is more like it for our stove).

finally, a big thank you to Woodsmans stove parts...I remeasured the grates we had, ordered what I think would fit, and they did, so now just the glass to replace and we'll hopefully be good to go for another season of warmth...

we did buy a new woodstove, up to 74K BTUs and hopefully 10 hours-to-coals burn time, so that should be good backup to our coal stove which can be a little underpowered when the temps go to freezing and the wind starts blowing. We've been able to get some free wood from downed trees in all the storms we had this summer, so with the 3 cords we have left over from last year to burn this year, and the six cords we'll season this winter for next year, we should be in good shape after the electric rates fly up beyond the heavens

" Hi Ellen, broken glass seems to be a common occorrence for the surdiac. Has anyone tried replacing with slightly thicker one piece glass? What model is yours?"

Hi there! I have a Gotha 513, and it heats my entire house! It is 18 years old. The glass on the front door needs to be replaced, and the local stove shop says to bring the door in. I can order the glass through Woodman's. Does anyone know how to remove the door?

I had a Surdiac for years, also had to replace a few pieces of glass. Never took the door off, was able to losen the bracket assembly that holds the glass in place enough to slide the broken glass out and install the new. Not easy but can be done. Good luck!

AvonMaine wrote:Hi there! I have a Gotha 513, and it heats my entire house! It is 18 years old.

Hi AvonMaine! We are looking in all directions for two good used stoves, one for upstairs and one for main floor. Each floor is about 900 sq. ft. Buying used fits our budget best. There are quite a few Surdiacs on Ebay and Criagslist, I like the looks of them. Our house is 1800 colonial with 12' ceilings, masonry/no insulation but there are new replacement windows. Currently paying $400+/mo gas heat. How long have you had your Surdiac and how much space/kind of space are you heating?

Hi there. The surdiac is our only source of heat. I have a tri level, which is the front half a house with a living room, dining room, and kitchen on the main floor, and then 6 steps up to 4 bedrooms, or 6 steps down to a playroom and laundry room at the back of the house below the bedrooms. This keeps the bedrooms and main floor warm, like 70-72 degrees, and the downstairs playroom and basement in the 60's. The main floor has 12 foot ceilings, and there is a cut-out high on the living room wall (that used to hold a fish tank) so the heat goes right up to the bedrooms. The hot water heater is on a timer, so that it's only on in the morning and evening. The last few days, with the temp in the single digits, things got cooler. I had to turn the heat on downstairs at night to make sure the laundry room didn't freeze up. It only gets this cold a few times a year.

It burns more coal than I would like - a bag (50 #) a day at $9.50. This house is huge, and the furnace used to run constantly to heat the whole place. I just replaced the glass and all the gaskets. I got Pyrex glass from the local glass company, and the gaskets from the hardware store. We have not vacuumed out the back vents for years, and I suspect it would help a lot. The coal dust is like talcum powder, and the whole stove needs to be vacuumed clean. The part we like the best is that there is always somewhere warm. You should see the cats camped out around this stove! We only need one blanket at night, because the bedrooms we use are right at the head of the stairs. It is a problem in in-between weather, and sometimes we either let it go out during the day, or open the door or windows. We had 16 for Thanksgiving, and it was very warm. It doesn't require any electricity, either, which is nice, because we lose our power at least once a winter.

So, do we like it? Yes! Would we get another? Yes. We used to have a wood stove, and the wood came with all kinds of mice and bugs. The coal is easier to store and carry in, but I have to dust and vacuum a lot more. I split a 50# bag into 3 big cat-food buckets, which I get from Sam's Club, so I can carry it and dump it in more easily.

We've had the stove since 1988, but only used it full-time for the last 3 years. Our house is 60 feet x 17 in the front, and 60 x 15 in the back. So it heats 1020 and 900 feet quite comfortably, and the downstairs 900 to the 60's.

Hey thanks AvonMaine! That's really good to hear. We were concerned about the high ceilings in our home and all the heat hanging at the top. Few more questions, what size coal are you burning and how often do you empty the ash and fill the hopper? Oh, can the Surdiac be direct vented?

We burn pea coal. It is burning a little faster than usual right now. I shake down the stove maybe 5 times a day, and empty the pans two or three times.. I fill the hopper twice, once in the morning, and once at night. It's burning about 50# of coal a day, but should burn less. I found it burned better if you shake it more often. I also open the front and give the coal a good stirring around, getting the burned stuff along the edges to fall through the grates. The more I shake it, the less "popcorn balls" of clinkers form. I just read on here last week, and have started shaking it by stabbing the poker from front to back. I used to go from side to side, but that made popcorn balls on the edges, and sometimes I had to take them out with tongs. This new way seems to work better.
Our Surdiac sits on the fireplace hearth, and is vented up into the fireplace. We had it installed by the stove company.

Thanks again Avon. I was just reading that some people find success burning less coal with a 50/50 mixture of pea and nut. Is this a possible solution for you? I am seriously interested in the Surdiac however, that kind of "tending to" may be a challenge. We may have to look at something a bit more automatic. There's alot to learn, hopefully not the hard way!!

If you are looking for two stoves then each one will not have to be fired so hard that clinkers form, and the need for such frequent tending will not be required. The stoves achieve high efficiency by using a relatively shallow bed which helps to burn volatiles and CO. The hopper feeds hot coal so output remains steadier than if batch fed. Heat exchange surface is large so stack temperature is low.

Hey thanks franco!! We have two seperate living areas in our home. We are downstairs while our son and his wife live above. They work exceedlingly long hours and would not be in a position to tend a stove but for two times a day, morning and night. We will have to direct vent while they have a chimney that runs through their living room. So, given the information you just provided do you think we could set up a surdiac or fanco belge on each floor and anticipate minimal tending? It seems like we would be able to pick up either one of these stoves at a good price in our neck of the woods, W. of Philly. I like the looks of either of these stoves too, and if they are going to be part of our living spaces it would be nice to enjoy their appearance!

Direct vent is not recommended because in the event of power failure the stove will keep burning with the strong possibility of CO gas leaking from the stove. You can run a stoker direct vent or pellet stove because the fire dies quickly without power. There is just a small amount burning at one time.

When burning pea coal and with the hopper set high for the deepest bed of burning coal you can go 12 hours or more with a Franco Belge if the burn rate is around 20 pounds. I can't speak for a Surdiac but I think it would be the same. Long burn times need a deep bed which neither of these stoves has. Alternative stoves on the used market with a more finished appearance are Haas & Sohn or Buderus from Germany and Godin from France. They also have their own set of problems though but will have long burn times. A lot depends on how much heat each space needs to select the right stove.