Coal stove as hot water heater

Chris · By: **Chris** On: Sun Jan 29, 2006 7:08 pm

When you add the hot water heater coil to a stove, how do you keep the water in the coil from not vaporizing while not drawing hot water. Do you keep circulating into a hot water tank?

AL-53 · By: **AL-53** On: Sun Jan 29, 2006 9:37 pm

Chris...I have seen setups where they use a hot water storage tank from a boiler setup..about 100 gallons...and they circulate till temp is reached...there are things you need besides the coil...pump...aqua stat..air valve....

plus most do not use coils anymore in the stove...they use a Stainless block type heat exchanger...

I was told if water is not used for awhile...they may blow off relief valve..so place discharge wisely...lol

look at page 21 for basic setup....

http://www.harmanstoves.com/doc/magnumstokerm.pdf

see if that helps

Al

stokerstove · By: **stokerstove** On: Sun Feb 05, 2006 12:28 am

Sorry for the late post - haven't checked in here for a while. I have a double hot water coil in my Alaska stove which is hooked to my existing elec. water heater. Pretty simple operation as you just create a loop in which the cool water flows from the bottom of the WH to the bottom of the stove coil, then exits the top of the coil into the top of the WH. If your WH or storage tank is within 10' of your stove you don't need a pump as the water flows on its own but if your like me the WH is more than 10' away and I need a small pump to circulate the water. I let my pump run constantly as it uses minimal elec. or you can use an aquastat which will turn the pump on and off at pre-set temps.
The list of supplies I used is:
Coil, pump, auto air bleeder, pop-off valve, 3/4" copper pipe w/ valves and fittings, and pipe insul. The aquastat is optional.
When I start the stove in the fall I turn off the elec. to the WH. The stove heats all of my water during the heating season which saves me a bunch on my elec. bill. This is one of the best investments I've made (about 5 years ago) and I did all the work myself (not the greatest plumber either).
I got the basic hardware and instructions from Alaska and the rest of the supplies from a plumbing supply.
If you need any more info on my system, just give me a shout.
Bob

wenchris · By: **wenchris** On: Sun Feb 05, 2006 3:34 pm

Bob, where did you get the instructions for the hot water coil? Checked the Alaska web site and they have no info there.
Thanx Jimmy

stokerstove · By: **stokerstove** On: Sun Feb 05, 2006 9:45 pm

Jimmy, The instructions came with the coil, which is called "The Hilkoil Energy Saving Hot Water Kit". The mfg. is Thermo-Bilt, Inc., Box 3207, Schenectady, NY 12303
I don't know if they are still making these or even if they are still in business but that would be easy to find out.
One thing I forgot was the addition of a tempering valve to prevent someone being scalded as the water temps can get very hot.
If you need the instructions and can't get them from the mfg. I could probably scan them and send them in an email.
I purchased the kit right at the Alaska main store in Bloomsburg, PA.
Bob

madrmc · By: **madrmc** On: Mon Feb 06, 2006 6:17 pm

Stokerstove, does the water coil mount in the top inside of the stoker? Do you just drill a hole to run the copper pipe in on one side and out on the other?

wenchris · By: **wenchris** On: Mon Feb 06, 2006 6:48 pm

Bob the company is still in busness thanks for the info. Could someone post some pictures of their hot water coil installed in their stove. This would be most helpful in seeing the layout of the pipes. I would love to do this but the stove is in the living room and I'm hoping that I can conceal the pipes. I have a magnum stoker so if anyone has a coil installed in said stove, are you happy with it and could you post some pics or e-mail them to me.
Thanx Jimmy

stokerstove · By: **stokerstove** On: Mon Feb 06, 2006 11:02 pm

madrmc wrote:Stokerstove, does the water coil mount in the top inside of the stoker? Do you just drill a hole to run the copper pipe in on one side and out on the other?

The coil mounts in the inside of the stove. 2 holes have to be drilled in the side of the stove. The coil isn't in the top - the bottom of the coil is a few inches above the grate. The coil itself is stainless steel.
If you do a google search for "Thermo-Bilt" you should get a result for a PDF file which has illustrated instructions on how the coil is installed.

BinghamtonNY · By: **BinghamtonNY** On: Tue Feb 07, 2006 2:33 pm

Stokerstove, What type of pump do you have? You set it too run constantly? I've got the coil already installed in my stove(mag stoker) just havent gotten to setting it up yet. (6 month old baby takes up a lot of time). I also have minimal plumbing skills but know I can do it. Any info would be greatly appreciated. Thanks in advance. -Ryan

endinmaine · By: **endinmaine** On: Tue Feb 07, 2006 4:33 pm

Here is a link to their website with a few drawings.

http://www.hilkoil.com/

I am also going to do this but am concerned about how big the storage tank needs to be ,, 100 , 200, 300 gallons ? Since my Harman III puts out a ton on heat , a 100 gallon tank of water would take no time at all to heat up. If there was no call for hot water then the relief valve would be blowing. I even thought about sending the excess hot water to a heater in my garage.

stokerstove · By: **stokerstove** On: Tue Feb 07, 2006 5:35 pm

BinghamtonNY wrote:Stokerstove, What type of pump do you have? You set it too run constantly? I've got the coil already installed in my stove(mag stoker) just havent gotten to setting it up yet. (6 month old baby takes up a lot of time). I also have minimal plumbing skills but know I can do it. Any info would be greatly appreciated. Thanks in advance. -Ryan

The pump is a Grundfos "Brute", Model #UP15-42F. I do have it set to run constantly and have no problems with the system. I've thought of installing a aquastat but I haven't been able to justify the additional cost. Running constantly doesn't seem to be an issue as far as elec. costs.

stokerstove · By: **stokerstove** On: Tue Feb 07, 2006 6:07 pm

endinmaine wrote:Here is a link to their website with a few drawings.

http://www.hilkoil.com/

I am also going to do this but am concerned about how big the storage tank needs to be ,, 100 , 200, 300 gallons ? Since my Harman III puts out a ton on heat , a 100 gallon tank of water would take no time at all to heat up. If there was no call for hot water then the relief valve would be blowing. I even thought about sending the excess hot water to a heater in my garage.

I am currently using my existing 50 gal. tank and the relief valve seldom blows off - can't remember the last time it did.
I just recently completed an extra loop off my system to a 4' hydronic baseboard unit in my unheated family room. I did this for the same reason that your talking about - alot of extra heat, especially overnight, not being utilized. It works ok and provides a modest amt. of heat where there was none to speak of. If I were to do it over again I would use a larger baseboard unit as the 4' doesn't suck off as much heat as I thought it would.

Oil Region · By: **Oil Region** On: Fri Feb 17, 2006 12:20 am

http://cgi.ebay.com/HOT-WATER-HEATER-HEATING-COIL-STAINLESS-STEEL-WOOD-COAL_W0QQitemZ6037221077QQcategoryZ41987QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Ebay has a HilKoil for a great deal. This is $37 less than directly from the hilkoil website.

I looked at my Harman DVC-500 this evening and I'm wondering if I can run one of these coils through the coal hopper from the back of the stove. The sides of the DVC have a double layer of metal about 2 inches apart for low clearance installations. Putting a hole through the side would not only be very difficult but also very ugly in our living room.

Any thoughts on running pipes through the coal hopper and into the stove from the back?

Troy