Water Coil In Coal Stove

Water Coil In Coal Stove

PostBy: traderfjp On: Wed May 17, 2006 12:27 am

I talked with my stove guy and he is adamant about NOT using a coil to make domestic hot water or to circulate water through the coils in my oil fired boiler.

His thoughts were that it was dangerous and that I would have lots of problems. He said that the water in the pipe could create steam and rip the pipes open and also that the stainless coil could fail inside the stove creating a mess and ruining the stove.

I'd love some opions and advice on what he said since I'm new at this but know plumbing. My plan was to use a circulator (Taco) and run my boiler water through the stove. The stove is going on the first floor and will also heat my upstairs too. I would love to use some of this heat for my boiler so I could heat my basement and keep a more even heat to the upstairs.

He did say that I could buy a coil from Alaska or Keystoker (haven't decided what stove I want) but that the coil only holds 3/4 of a gallon and is basically useless.
Thanks in advance.
traderfjp
 
Stove/Furnace Make: Alaska
Stove/Furnace Model: Channing 3

Re: Water Coil In Coal Stove

PostBy: Richard S. On: Wed May 17, 2006 4:49 am

traderfjp wrote:I talked with my stove guy and he is adamant about NOT using a coil to make domestic hot water


Many people do quite sucessfully.

or to circulate water through the coils in my oil fired boiler.


Don't know why you want to do that or if you can.

He said that the water in the pipe could create steam and rip the pipes open and also that the stainless coil could fail inside the stove creating a mess and ruining the stove.


Never heard of that happening and even if it did short of the pipes exploding and causing damage it is just water. Considering the fact that these coils have been in use for at least 30 years (probably longer) I doubt that they would be able to still sell them or would if that was a problem.


He did say that I could buy a coil from Alaska or Keystoker (haven't decided what stove I want) but that the coil only holds 3/4 of a gallon and is basically useless.


I don't know what the volume is but due to the design they can heat incoming water very quickly. It takes a while for the heat to disipate enough to the point where it would become cold enough for example to not take a shower. Can't give you a time frame since our system goes directly into the gas hot water heater but I'd guess you would at least get enough hot water to take a quick shower probably more.

Besides routing it directly to the hot water supply is not how you set it up. You hook it to your current hot water heater. When the hot water is in use it tempers the cold water coming into the system. When it's not in use it circulates in a loop keeping the hot water in the heater hot negating the need for it run using gas/electric. This can be done naturally or with a small pump. Essentially it becomes a holding tank, I'd imagine you could even get a insulated tank and that would be all you would need for an adeqaute amount of hotwater. Cost is minimal if anything because most of the energy used to heat this water is going to be wasted during times when then the stove is not making heat for the house. Coal is always burning and this is one way to grab some of that unused heat.

As far as using it for baseboard unless it's a very small section I wouldn't reccommend that.
Richard S.
 
Stoker Coal Boiler: Van Wert VA1200
Coal Size/Type: Buckwheat/Anthracite

PostBy: stokerstove On: Wed May 17, 2006 7:40 am

It is a safe system if done correctly. A coil in my Alaska Stoker Stove heats ALL my domestic hot water during the heating season and never had any problems yet.
A month or so ago there was quite an extensive post on this forum on how the system works.
Don't let someone talk you out of adding a coil, just make sure you do some research first.
stokerstove
 
Hot Air Coal Stoker Stove: Alaska Kodiak Stokerstove 1


PostBy: coalkirk On: Wed May 17, 2006 8:14 pm

Why don't you just buy a stoker boiler? If you already have hot water heat, that makes more sense. You can pipe the coal boiler supply into the return side of your oil boiler and all your zones will work as normal, but you won't burn oil
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

PostBy: FedFire47 On: Fri May 19, 2006 7:05 pm

The coil is in fact only 1/2" pipe. I can't speak for other funaces, but the Keystoker I have, the coil is about 20' long. Keystoker claims it will deliver 200 gallons per hour hot water. Don't know if that is correct but I can tell you I have never run out of hot water since I installed the furnace.
FedFire47
 

PostBy: TechCurmudgeon On: Sat May 20, 2006 1:48 am

I know nothing about oil-fired furnaces, so take these opinions with a grain of salt, but I don't see any problem so long as standard plumbing practices are applied. For instance, a pressure relief check valve must be installed in case excessive pressures are encountered.

In the unlikely instance if the water coil breaches inside the furnace, and puts out the fire I'd suppose the same safety circuit that stops pumping oil into the burner in the event of a 'fire out' condition would still kick in (although there would be one hell of a mess to clean up).

This could be mitigated by installing a solenoid valve on the feed water side, and only allowing water flow when the burner is not faulted (but then, being ignorant of oil burners, I don't know that such a 'burner fault' signal exists that can be exploited in this manner).
TechCurmudgeon
 

PostBy: traderfjp On: Sat May 20, 2006 10:30 pm

Thanks for all the replies. Now that you guys tell me its safe the real issues is getting enough surface area with the coils to make it worth while. I really don't want to add several horse shoe type coils that need to be plumbed together. I'd like one large coil with an input and output to reduce the piping for apperances (first floor install). With the heat the Coal stoves put out I'd be afraid to make my own out of copper.

Currently I have a seperate oil fired hot water heater and a oil fired boiler. In my boiler, I have coils for making hot water that I haven't used them in 14 years.

I was thinking of running the hot water generated from the stove into the pressure releif valve inlet and then create a loop back to the stove using the boiler drain for an outlet. I have a Taco pump so it would be easy to circulate the water in a loop. Does this sound reasonable? I was even thinking of turning on the coils in my boiler to feed my hot water heater. I may be expecting too much out of this stove. I also don't know if the Alaska Channing 3 has the space inside for all these coils. I'm also wondering what happens if the power goes out and I have a backup for the stove but not the pump. Could the stove create steam and burst the pipes? Thanks in advance.
traderfjp
 
Stove/Furnace Make: Alaska
Stove/Furnace Model: Channing 3

PostBy: coalkirk On: Sun May 21, 2006 7:15 pm

For what you are describing you would like your coal burner to do, you are describing a coal boiler. A coal stove with a coil will not be adequate. Also, you cannot eliminate your pressure relief valve. before you spend the money on a coal stove, you should really look into a boiler. A coal stove will heat a large space and your home will be very warm in the area near the stove. The further you get from the area with the stove, the cooler your home will be. If you use a coal boiler, your home can be a uniform temperature, using your existing zones.
coalkirk
 
Stoker Coal Boiler: Harman VF3000
Coal Size/Type: antrhcite/rice coal

PostBy: traderfjp On: Sun May 21, 2006 8:08 pm

I can't have a boiler because I don't have access to my basement. I'm hoping the stove would satisfy most of my heating needs. I have an open floor plan and can move some air. Since the stove is going on the first floor I wanted the stove to do the heating in the basement with the coils or atleast take some of the load off my oil fired boiler. I was thinking of putting in three coils or one very long one that wraps around. I also have no intention of removing my pressure relief valve. I would however pipe it outside incase it opens up. My basement is about 400 sq. ft.
traderfjp
 
Stove/Furnace Make: Alaska
Stove/Furnace Model: Channing 3