Can I use a coal stove as a coal boiler?

Can I use a coal stove as a coal boiler?

PostBy: Avy On: Thu Jul 17, 2008 11:03 am

I've been reading the site for a few weeks now, and I'm amazed at the helpful and insightful people here. What a great place to come to for all kinds of info!

I was unable to get a coal boiler in time for this cold season, so I had to get what I could find, a coal stove (Keystoker 105 Direct Vent).

My question is, can I add a DHW coil or 2, and use the stove in the basement (unfinished) in series with my oil boiler (Dunkirk Empire II) to heat the home using it's current hot water baseboards (2100sqft, well insulated) and use it for DHW also? I would rather not have to use the oil boiler at all if possible. This sucker is HEAVY and I only want to move it once ( I unload it tonight to the garage, then await some feedback before i move it again haha). If it is better off on the first floor and maybe just adding a DHW coil to it for my hot water needs, then thats what I'll do, but I'd rather it heat the home with the exisiting hot water baseboards if it can handle that (or if it's even doable!)


I have looked for a while for a similar question on the forum, so as not to post something that has already been answered. My apologies if I missed it!

Anywho, thanks in advance for any input, I'm a total newb to coal stoves/boilers but I have no problems learning and doing things myself.
Avy
 
Stove/Furnace Make: keystoker
Stove/Furnace Model: 105 DV

Re: Can I use a coal stove as a coal boiler?

PostBy: Sting On: Thu Jul 17, 2008 11:09 am

Anything is possible

but short answer

no :roll:

The DHW coil and heat exchanger(s) will maybe get your old oil boiler warm - not warm enough

enjoy the stove this winter - fire the oil boiler when you need the extra to keep the rest of the house above 50 - and use both for the best of both worlds (next season) when you finally get your coal boiler installed.
Sting
 
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Re: Can I use a coal stove as a coal boiler?

PostBy: LsFarm On: Thu Jul 17, 2008 2:05 pm

The amount of heated surface area on one or even two hot water coils is a small fraction of the heated surface area in a boiler,, there just isn't enough BTU' capacity in the pipes to supply enough heat to heat a house... a single coil will do a good job preheating a 40-50 gallon water heater for a families' moring showers,, but the coil just isn't able to keep up with baseboard heating for a whole house.

There are a few talented experimenters who have made a custom coil with lots of surface area, and are using this to heat a portion of a house, or a section of hydronic heated floor... this may be an option for you..

Do a search for 'custom hot water coil'.. maybe you can find the thread and photos.

Greg L

.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland


Re: Can I use a coal stove as a coal boiler?

PostBy: jpen1 On: Fri Jul 18, 2008 12:09 am

I guess I am one of the experimenters as Lsfarm mentioned you can search my post using the advanced search options for my coil thread(s). Greg is right you need much more surface area than is availible using a hotwater coil(s) in a stove. My custom coil has about 3.5 times the surface area of the largest commercially avaliable coil made to fit my stove. The coil just heats my oil boiler enough to heat the domestic hot water. Another obstical is the draft loss out the boilers chimney which exponentially in creases the amount of surface area needed to heat the water vs say heating the water flowing into a elec. hot water heater. So bottom line is put the stove on the first floor if possible and if your boiler heats your hot water you can try a commercial coil but I don't think it is going to have enough umph to be worth the cost unless you have an indirect tank style.
jpen1
 
Stove/Furnace Make: Leisure Line
Stove/Furnace Model: 110 Boiler

Re: Can I use a coal stove as a coal boiler?

PostBy: Avy On: Fri Jul 18, 2008 7:49 am

thanks for all the input!

i was a little optimistic about the idea, when i called the folks at thermo-bilt coil and they told me 2 of the 21" coils in the 105 would be able to heat the home, but i got skeptical when i didnt find any posts here mentioning anything like that. i measured the inside of the 105, and i'd only be able to get two 18" coils inside anyway.

im thinking now of plumbing 2 coils to a tank and suppling just dhw to the home, and keeping the stove on the first floor.

a real bummer i read last night in the manual stated that the vent had to be 3' from an inside corner- which puts me under a window, which requires 4' distance (since it is under the window), which i cant get in the location i wanted the stove. any one know why they have a 3' from an inside corner clearance stated?
Avy
 
Stove/Furnace Make: keystoker
Stove/Furnace Model: 105 DV

Re: Can I use a coal stove as a coal boiler?

PostBy: Sting On: Fri Jul 18, 2008 9:36 am

lets think about this for a moment

your new coal stove (Keystoker 105 Direct Vent).

What is its potential output???

And if you strip (pump) 30 or 60K of that out put, via your hybred wet heat exchanger system - to the existing oil boiler system.

What will be left to heat the area the keystoker is in? There is no free heat - only the stove potential. If you have a greater load than that potential - the stove simply will not heat.

I submit - you will be cold, surprised, and unhappy. :o
Sting
 
Other Heating: OBSO Lennox Pulse "Air Scorcher" burning NG

Re: Can I use a coal stove as a coal boiler?

PostBy: Avy On: Fri Jul 18, 2008 9:56 am

105,000 btus. A calc i did on the home came up with 80,000 needed to heat it. if it were in the basement, I wouldnt need to heat the basement, just the oil boiler system to heat the house via hydronics, so all the heat could go to that.

My thought now was to add a coil or 2, bring up a loop to the stove and down to the basement to a tank and circulate water to a 60 or 80 gallon holding tank for DHW. I'd use the stove on the first floor living area to heat that floor and hopefully the upper floor. this would enable me to not use any oil this winter, or very little if the DHW demanded it.

surprised would be ok if i can just close the loop for DHW and not use it and use oil this year, if the stove couldnt handle that. cold and unhappy the wife wouldnt tolerate, however :lol:

EDIT:
Got in touch with keystoker, the vent being 3' from an inside corner rule is for an L shaped home, the 'inside' OUTDOOR corner, reason being the wind currents that can be generated in that space. i thought they meant from the inside of the home, i feel like such a newb now! :oops:
Avy
 
Stove/Furnace Make: keystoker
Stove/Furnace Model: 105 DV

Re: Can I use a coal stove as a coal boiler?

PostBy: LsFarm On: Fri Jul 18, 2008 11:01 am

AVY, well at least you got an answer, and if the info in the manual didn't explain the inside, outdoor corner to be the issue, then it needed explaining..

There are several threads on hooking up a DHW coil, using circulators, aquastats etc to control the circulation etc.. Sit back and read,, there is a lot on the subject,, and since every install differs,, there is no single answer to 'how?' to plumb and control a DHW circuit..

Greg L

.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland