Which Coal Furnace to Buy

i am planning to buy a add-on coal furnace. I would like a rice coal automatic feeder am planning to hook into exsisting duct work of propane furnace which company or specific furnace should I look at
plan to spend $2000-$4000 dollars and will be heating 2750 sq ft.

Consider adding a stoker boiler instead of a furnace. You can have a water to air coil installed in the duct work for your heat and the boiler can provide all of your domestic hot water as well. I use a Harman VF3000 and am heating approximately the same square footage as you are. If you have separate duct trunk lines, say to the first and second floors, you could also zone your heat by using two smaller water to air coils.

CoalKirk is giving good advice. The problem with a furnace is that the heat needs to be turned off once the house has reached the desired temperature, And a furnace can't store heat. And you can't just turn off a coal fire, even with a stoker feed. The furnace can get too hot and the heat has to go into the house, overheating your living space.

With a boiler, the water temp can be set at say 140* and once the house has reached the desired temp, the water to the water/air exchanger can be shut off, [with a zone valve] and the coal fire in the boiler slowed down. The water in the boiler can still climb and retain the excess heat untill it reaches 210*+. By then the house may desire more heat, or a heat dump system can be set up to dump heat into a garage or other non-living space to control water temps.

With a hot water boiler you can save on your domestic hot water as well, as Coakirk said.

All the above said, if you are a do-it-yourselfer, take a look at this item on ebay:
**Broken Link(s) Removed**You may find it an interesting possibility, although I'd still recommend a boiler.

Hope this helps Greg L

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LsFarm wrote:CoalKirk is giving good advice. The problem with a furnace is that the heat needs to be turned off once the house has reached the desired temperature, And a furnace can't store heat. And you can't just turn off a coal fire, even with a stoker feed. The furnace can get too hot and the heat has to go into the house, overheating your living space.

With a boiler, the water temp can be set at say 140* and once the house has reached the desired temp, the water to the water/air exchanger can be shut off, [with a zone valve] and the coal fire in the boiler slowed down. The water in the boiler can still climb and retain the excess heat untill it reaches 210*+. By then the house may desire more heat, or a heat dump system can be set up to dump heat into a garage or other non-living space to control water temps.

With a hot water boiler you can save on your domestic hot water as well, as Coakirk said.

All the above said, if you are a do-it-yourselfer, take a look at this item on ebay:
**Broken Link(s) Removed**You may find it an interesting possibility, although I'd still recommend a boiler.

Hope this helps Greg L

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LsFarm, has CoalTrol made any advancements for controlling furnaces; since you made this reply to Greg L?

I have a coal add on furnace. It's a Newmac GAO (Grated Add On). It works good, but it is hand fired. When I bought it I didn't know about stokers. I'll use it till it rusts out, then install a coal fired boiler and steam rads in the house. My ductwork is crappy and I still have cold spots that heat can't reach via blower. piping steam will solve that.

With your size of house, something like mine except mine is leaky, I'd go with the biggest unit you can find. I know Newmac sells a large hand fired coal boiler for residential use. I too am through with doing wood - I've been at it for all my life, and frankly have neither the time or energy anymore to slug and cut and split and stagger around in the bush.

Look at Newmac for an add on.

LsFarm and Greg L are one and the same.... ME !

I still stand behind my statement that a coal fired boiler is better than a furnace... you can place the boiler anywhere, and run hot water pipes to the furnace hot air plenum... you can heat your domestic hot water.. that's about 20-30% of your heat bill, and water can again store heat.

I'm not aware of a Coal Trol for a forced air furnace... I thought that the Coal Trol was for living-space stoves.. But I certainly could be wrong.. Even with a Coal trol, the ease of heating domestic hot water, and hooking up the unit, and the ability to store excess heat are all plusses that point me toward a boiler.. with a water to air coil in the hot air plenum.

Greg L [LsFarm]

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A boiler will turn more of your coal ($$$$) into usable heat too as they operate at much lower stack temps. Water is a much more efficient media to transfer heat than air is.

In theory the boiler with heat exchanger in your duct work is the way to go; but, unless, you can perform the installation yourself, the cost will be prohibitive when attempting to replace/augment a FHA system. When I started my alternative heating solution quest about a year ago, I was also convinced a boiler and heat exchanger was the best way to augment/replace my existing propane FHA system---then I started calling some HVAC folks to come in and provide estimates... After deciding hitting Power Ball wasn't a viable solution, I started doing more research at this web site; and, any other information I could glean from the Internet. Props out to my local Keystoker dealer too. He was extremely helpful. He actually has an Alaska 140 heating his house. He recommended the Koker due to the much larger coal hopper.

Now I'm pretty handy around the house with a well equipped shop; but, installing a boiler, heat exchanger, plumbing, wiring, etc. will not be for the faint of heart. Plus a boiler will cost significantly more than a furnace---your inital cash outlay will be significantly more with a boiler, pushing your break even point out significantly further. Bear in mind: I'm not against boilers. If I had a FHW system, I'd use a boiler too, that's a no-brainer.

I ended up with a Keystoker Koker FHA thermostat controlled furnace (~160K btu), with cold air return and hot air supply plumbed into my existing FHA system---and I couldn't be happier. Using a single digital programmable thermostat and heating a two story ~4000 sq ft house, my indoor temperatures vary only 1-2 degrees throughout. I don't see any advantage a boiler would offer; except, perhaps, being slightly more efficient, burning less coal. Running the numbers thru Excel, the payback would be a long time, even with the price I paid for coal in southern New Hampshire...

The only change doing the project over again would be to simply use ambient air for the Koker's convection air intake; and, plumb the hot air supply directly into my propane system cold air return, using the propane convection/distribution fan to move the hot air around the house. Reason? The cost of running a simple verticle duct up to mate with the cold air return would have been significantly less. Leisure Line's web site has a nice diagram of how to make this work:

http://www.leisurelinestoves.com/1904137.html

You'll need to keep your basement door cracked to supply a "secondary" cold air return path too... And run a wire from the coal furnace over to the existing furnace to turn on its convection fan to move your hot air around---easy stuff.

Bottom Line: Although only 3/4 of the way through my first coal burning season, my Koker furnace has worked like a champ. I haven't run my payback calculation lately; but, my last propane delivery was only 50 gallons @ $2.49 back in January. At last year's prices ($1.90s) I burned $3300 worth of propane AND FROZE MY ARSE OFF. This year I'll burn $2000 worth of coal; and, ~$500 worth of propane AND I'M WARM AGAIN!!! Plus my body isn't going into convulsions every time the furnace kicks on... With my Koker, I've burned ~6 tons of bagged anthracite so far this winter, my whole house is nice and warm, including my basement, which used to be freezing cold with the propane system. I stll have about 2 tons of bagged rice left for the rest of the season. Depending on the weather, I estimate using another 1.5 tons before shutting down in late April - early May.

NOTE: I still burn propane for my clothes dryer and hot water heater. I bought a hot water coil for the Koker; but, I haven't plumbed it in yet---long story...

My 2 cents! Unless the price of coal goes through the roof, you'll be saving big time going coal. And WRT huge demand driving the price of anthracite up: I believe there are enough carbon credit tree huggers out there who are dumb enough to buy into the liberal global warming baloney. These same folks will continue to view "carbon spewing" anthracite as an environmentally unfriendly fuel and pay exhorbatant prices for oil and gas. Those of us who are burning anthracite know better!!

Sorry for the diatribe; but, I grew up in NEPA with burning anthracite being the "norm." Unfortunately, most of these homes were converted to oil in the cheap oil '80s. Now many of these folks, many of which are my blood relatives and close friends, are seriously considering converting back to anthracite. Plagiarizing from Yanche---Coal: Back to the future!

Good post watkinsdr... yes labor for a plumber to install a boiler and water to air exchanger could be expensive... I wonder if you would do a bit of record keeping... I'm really currious what your flue temps are in the Koker furnace, both when idling and when making heat...
I really think that most boilers are able to get more of the heat out of the coal and send less up the chimney than a furnace, but I'd like to see some numbers on this.

The other item you need to include in you calculations is the domestic hot water heating... this is significant... it will greatly reduce your payback time for the intial investment... Especially if you include year-around domestic hot water...You can run boiler year round to heat hot water. What is your propane bill during the summer months??? You will only be burning propane for clothes drying if you used coal for hot water..

Not all of us are do-it yourselfers, so I understand the financial constraints on a boiler install.. I'm glad to hear you are happy with the furnace.. I wonder if the plumbers will start to drop their brain-surgeon prices now that the housing industry is slowed way back??

Greg L

I "relocated" my gas barbeque meat thermometer to my exhaust flue early in the heating season. With a range of 140 to 850F, this thermometer should be ideal for monitoring flue temp---plus, I never used the dang thing on the BBQ anyways... I also placed a magnetic stove thermometer on the front of the furnace, basically at the hottest location in front of the heat exchanger. With the Koker "idling" (with my current maintenance fire setting) the stove thermometer usually reads 300F, flue temp 180F, with the barometric damper just slightly open. With the Koker running "full blast" the stove thermometer usually reads 550F, flue temp 280F, with the barometeric damper open and operating proportional to weather conditions outside. Via experimentation, by purposely holding the barometric damper flapper closed, the flue exhaust will rapidly rise to about 380F when running at full tilt.

NOTE: I currently have my maintenance fire timer set with 6 timing pins for each 10 minute period. I had a CO problem Presidents Day weekend during the 60 degree Monday we were having---also freaked out my wife... Amongst the list of things my Keystoker dealer recommended was to crank up the maintenance fire to keep a good draft flowing. I still need to experiment with throttling the maintenance fire back some; because, this will be way too much heat during the warmer days of March and April. Bear in mind: I have a nice 30' masonary lined chimney. In theory, I throttled the maintenance fire back too much, causing the chimney to cool down, losing draft. I'm saying in theory; because, I did several things all at the same time to completly eliminate the CO problem. I still haven't traced the problem to root cause; but, I've eliminated the problem.

The Koker has a conbustion fan which runs continuously. Since this fan was doing such a good job keeping such a small fire burning, I purposely removed timer pins from the maintenance fire timer box. As delivered, the Koker came with 6 timing pins installed; which, caused the furnace stoker to run ~90 sec every 10 min. I throttled it back to 3 timing pins, running the stoker for about 45 sec every 10 min---I'm assuming this wasn't enough flue temp for my application. During the middle of my CO problem, I increased the number of timing pins to 8 pins per 10 min. Since this was basically keeping the stove kranking all the time, I've since throttle back to 6 pins/10min again---basically the same setting the furnace was delivered with.

I should probably post this as a new subject in the Forum and get some feedback on this problem...

I'm anxious to get my domestic hot water plumbed in with my Koker's hot water coil. I've pretty much resigned to making this a summer project, after shutting down for the spring. Agreed---there will be significant savings after completing the DHW phase. I'm also assuming I'd have the same draft problem with a boiler generating DHW in warm weather.

Up here in southern New Hampshire, last year, the HVAC contractors were still making easy money on new system installations---obviously based on the 3 quotes I received. As a matter of fact, the two guys who installed my duct work last September have since been laid off by the company they worked for. The construction market has slowed down significantly up here. Perhaps getting an installation done now would be more reasonable.