# 12 volt outside wood burner



## NorthernMich (Apr 30, 2006)

is there a unit that heats a radiant heated home with a 12 volt electrical unit?

Thinking it would be easier to run by solar/battery than a conventional 110 unit...what is a good backup to my natural gas system...I have ICF with pex tubing.


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## Harry Chickpea (Dec 19, 2008)

No, for a variety of reasons.

1. There is no way you can get enough power out of a solar setup for heating a home. Even a single stove burner is above the capabilities of most systems.

2. To run a 12 volt cable with that amount of amperage, you would be spending a fortune in welding cable.

3. That much capacity in a DC system is dangerous.

4. Solar power/heat and times when heat is required tend to be mutually exclusive.


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## NorthernMich (Apr 30, 2006)

maybe I did not explain enough....12 volt JUST to run the outdoor boiler pump...that should be able to work...a 12 vdc pump runs a camper


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## Jim-mi (May 15, 2002)

Oh you can make a solar system heat a home . . . BUT . . .only in the middle of the day--if--the sun is shining......
Your going to need a pretty hefty battery bank to draw from to heat that home at night.
Yes there is some hefty 12vdc pumps available . . . .Big wire to supply big current . .not cheap.
That 12vdc pump in a "camper" is a lite intermittent duty pump that sure wouldn't last very long running 24/7....


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## Tall Grille (May 4, 2011)

There are plenty of 12V pumps available. You may have to do some research to find the flow that your system will require. Too much flow and the water will not have enough time to release the heat into the system, not enough flow and the water will cool before it has time to release the heat into the system.
Some times you need to experiment, maybe you have an ingenious idea that nobody has thought of before, maybe your idea is stupid, and you will learn a good lesson in the process.
I am looking into having a dual system, using 12v DC power for LESs and a AC system for appliances. It seems that a lot of power is lost, and money is spent in the conversion from DC to AC. Why not use the power as it is generated and stored.


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## wy_white_wolf (Oct 14, 2004)

Taco makes DC pumps that work on thermal solar systems and you should beable to find one that has the right flow for your boiler.

Put don't expect the battery or solar system to power it to be small or cheap. They could easily top the cost of the boiler.

added link

http://www.builditsolar.com/Projects/SpaceHeating/Components.htm#Pumps

scroll down for DC pumps

WWW


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## artificer (Feb 26, 2007)

Tall Grille said:


> There are plenty of 12V pumps available. You may have to do some research to find the flow that your system will require. Too much flow and the water will not have enough time to release the heat into the system, not enough flow and the water will cool before it has time to release the heat into the system.
> Some times you need to experiment, maybe you have an ingenious idea that nobody has thought of before, maybe your idea is stupid, and you will learn a good lesson in the process.
> I am looking into having a dual system, using 12v DC power for LESs and a AC system for appliances. It seems that a lot of power is lost, and money is spent in the conversion from DC to AC. Why not use the power as it is generated and stored.


Concerning flow: Too low of a flow rate, and you can not pump enough heat. The beginning of the radiant system is warm, but the end is cool. With a pump that is too big, the temperature between the incoming water and outgoing water are very close to the same temperature, but you have significant piping losses. The piping losses are the power it takes to achieve the high flow rate. Since it doesn't really get you anything for heat transfer, it's wasted energy.

Time the water stays in the heating section doesn't really enter into the picture, except that its part of the flow rate. The real things to consider are the flow rate (gpm) and the temperature change between the incoming and outgoing water (delta T). The more flow and higher change in temperature, the greater the heat pumped by the system. The goal is to find out how many btu's of heat per hour you need, and choose a maximum temperature difference. Using (BTU/hr/500) x (delta T) = the gpm needed.

With the wiring, I could argue that converting to AC for long runs will be a wash as far as efficiency is concerned. It all depends on the distances run, the voltage of the battery bank, and the size/type of motors used on the pumps.

Michael


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