Wood stove water heat
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Wisneaky
Minister of Fire
What pump and solar thermostat control are you using? How long does it take to heat that 50 gallon tank?
I have a Taco 007 stainless pump and a SolarHot controller. The pump runs on temp differential so it cycles. Takes about half the day to get the tank into the low 100s. My water heater is an insta hot so there is no other hot water stored except that in the preheat tank. I usually turn off the insta hot most of the time in the winter when I have the stove running. I have never had an overheat on the hot water, I generally do not burn raging fires in the stove.
Is that a Mansfield? I did not know that comes with a rear vent. How dry is the wood you are burning?
I would really like to do something similar in my basement. That way I can heat the basement with the stove and also supply hot water to my 1st floor baseboard heaters
We rarely have power outages here. If it did go out I would just plug the pump into a UPS off the computer. If it stayed out I have a small generator.
It is a hearthstone stove. I would have drilled the side and had the coil exit there, but I did not want to damage/alter the stone. By exiting through the top plate for the non-used chimney vent the stove is unaltered.
My wood is usually dried for one year. I burn whatever wood I can get, usually a lot of fir, hopefully alder.
My original plan was to add baseboard heaters in my basement to control overheating. I have had the system for over a year and have never had the water in the tank hit 120 degrees yet, so abandoned the idea.
The hearthstone heritage is convertible to either top or rear venting. The movable plug for the unused flue exit is a great place to enter the stove since it is replacable and a non-destructive modification.
I just worry about the whole explosion potential when the water turns to steam.
Was this a water heating kit? Or all homemade?
I just worry about the whole explosion potential when the water turns to steam.
Was this a water heating kit? Or all homemade?
I have ran the stove with the pump turned off for over an hour as a test and the water did not boil in that time frame. Even so, if there was a worst case and there was boiling the expansion tank would absorb it. After that the pop off valve would allow the pressure out. The only way there could be an explosion would be if the service/isolation valves were left shut. I have debated adding another pop off valve at the stove but have not seen any need after monitoring it. You can see on the stove I have both a temp and pressure gauge. Neither is really needed but they were fun and added to the steampunk look of the setup.
I am not sure I understand the question. Are you referring to the water preheat tank?
I really like your ingenuity. However, if I did something like that to my Hearthstone Equinox I'd be committing adultery to a really beautiful stove. Just can't see me doing it.
If you are a railroad buff, you could make the whole thing look like a mid century steam locomotive - that would be awesome, especially with a steam whistle.
If you are a railroad buff, you could make the whole thing look like a mid century steam locomotive - that would be awesome, especially with a steam whistle.
I had the stove for over a year before I installed the coil. I could not bring myself to drill the stone. My original plan was to go on the rear and hide everything. I settled for entry through the unused top chimney plate. I made a new plate, drilled and powder coated that. I then made a template for the coil and had a friend bend it. He got the size perfect. Then I added the check valve and guages. The tubing on the stove is 3/4", the delivery pipes to it are 1/2". This makes the water capacity a little extra as it warms up. The thermostat is a few inches away from the exit point on the stove to help prevent short cycling on the pump.I really like your ingenuity. However, if I did something like that to my Hearthstone Equinox I'd be committing adultery to a really beautiful stove. Just can't see me doing it.
No, it would not. Water flashing to steam results in a huge expansion of 1600 times. That's 1600! So the one gallon of water in the coil can become 213 cubic feet of steam all of the sudden at the boiling temp. 213 cubic feet is like a single car garage with a ten foot ceiling.
The speed at which it expands may exceed the speed at which it can exit through the small pop off valves and/or half inch pipe.
These are the reasons that boilers are certified and your stove mod is not.
It's good that your power is reliable. Hopefully the power goes out when you are home and not away. Locally I wouldn't trust it and would invest in dedicated UPS that could run for at least 2 hrs. What safety systems have been built in?
When I first installed the system I did have a dedicated UPS on it. When I tested the system for overheating I had it burning for a long time, without circulation, and did not even come close to the overheat temperature. The UPS failed and I just never put one back on it, figured if necessary I would just move my computer one onto the system temperaryly.
The coil in this stove is not directly in the fire box, it is above the baffle plate. This is likely why it does not get overheat issues when the pump is off. I also have never built raging fires, likely a factor too. I have never intentionally tried to overheat it, just as I do not intentionally overheat the stove.
I have not, just as I would not tell them if I modified my kitchen or if I modified my car. An interesting part of this part of the conversation is I work for a City, am friends with the plumbing inspector. I asked him his feelings on the system and he told me he rarely sees these systems anymore, but used to work for a smaller more rural town. He said he used to see them all the time and he would have no problem with them.
I do agree that your insurance company would likely say no if you phrased it to get that answer. But it is actually not up to you to run to them every time you do anything to your house or car. They may want you to, but can not require it. The most they can do is not renew your policy. They are still required to pay any claims that happen on your house, even if you remodeled your kitchen, added a room or installed a stove without their permission.
the ability to instantly boil a gallon of water would take a tremendous amount of energy
They are not required to pay if you purposely modify a ul listed product voiding its listing and making it potentially unsafe. Believe me they don't have to pay in that case i have gone on enough insurance evaluations to say that with absolute certainty.
This forum software is frustrating:GRrr
The amount of water that will convert to steam during a boil situation in a small fraction of that. The expansion tank will take the first wave of the shock, the pop off valve would grab the next part. That is if it were to flash boil, which I can not get it to even come close to. Sealed off certified boilers, hot water heaters and even sealed off uncertified wood stove water heaters can and will blow. The system has both expansion and pleasure relieve on it, it is not sealed.
Again, I have tested this system and did not ever approach boiling. I have both a pressure gauge and a temp guage right at the stove. When I posted the pic and started explaining the stayed it was not solely to spread a little info. I know some people want someone else to allow them permission with whatever they do. I am personally a Libertarian who just wants to live life without asking the permission of a certification agency in the government for permission in life.
The amount of water that will convert to steam during a boil situation in a small fraction of that. The expansion tank will take the first wave of the shock, the pop off valve would grab the next part. That is if it were to flash boil, which I can not get it to even come close to. Sealed off certified boilers, hot water heaters and even sealed off uncertified wood stove water heaters can and will blow. The system has both expansion and pleasure relieve on it, it is not sealed.
Again, I have tested this system and did not ever approach boiling. I have both a pressure gauge and a temp guage right at the stove. When I posted the pic and started explaining the stayed it was not solely to spread a little info. I know some people want someone else to allow them permission with whatever they do. I am personally a Libertarian who just wants to live life without asking the permission of a certification agency in the government for permission in life.
Ok but don't complain if something does happen and your insurance company doesn't pay up.
By looking at it it looks like you have done it pretty well and it is probably pretty safe. but when you say your insurance company is required to pay that is just not true.
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