Why Shouldn't You Solder a Water Coil?

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Post Thu. Jan. 24, 2008 4:54 pm

As the topic says, why shouldn't you solder a few copper pipes together to make one long water coil inside a stove?

Solder melts at between 360 to 370 °F, if you have water constantly running through it, your water would boil before the solder would start to give. Is it that people are just afraid to do it in fear of a leak? I've been thinking about this and would like some opinions/ideas.

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Post Thu. Jan. 24, 2008 5:47 pm

Yes, the inside of the stove can get quite hot and with the water under pressure, the solder joints could fail over time.
I wouldn't want to try it. I wouldn't want my water line leaking in my stove, especially if I am not home, it could be a real disaster! and with the stove being semi-tight, it could fill up with water.... :)

You can probably get custom coils made to almost any size/length...

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Post Thu. Jan. 24, 2008 5:55 pm

The copper pipe is thin walled, the melting [yield point] is low. Solder is even lower... If the loop ran dry or boiled, you would have a leak almost immediately.

You could give it a try, but install some kind of automatic water-check-valve so that if it leaks, it won't turn your stove into an aquarium !!

Greg L

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Post Thu. Jan. 24, 2008 5:56 pm

Why not just use the flexible copper tubing? :idea:

Or is that more susceptible to melting?

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Post Thu. Jan. 24, 2008 6:24 pm

"Coal and copper" ... not a good combination. The coal produces sulfuric acid, which eats the copper up.

Use the copper on the outside of the stove or stainless steel on the inside.
Last edited by Dallas on Sat. Apr. 01, 2017 12:14 am, edited 2 times in total.
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Post Fri. Jan. 25, 2008 7:41 am

Wow, thanks for the information! I guess I'll stick with my schedule 40 pipe :)

Again, thanks!

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Post Sat. Jan. 26, 2008 7:52 pm

Silver braze it.

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