I'm trying to build a camping hot tub. I've done it roughly before, just by a coil of gal pipe in a hot fire and water pumped though with a little electric pump.
It's great for the kids to have a nice hot soaking in before bed, and then the adults can get in. All good fun. Takes a few hours to heat up 600 litres of water to 40 degrees. '
But I want to do it properly. So I bought some 3 mill steel and some 1 inch gal pipe and fittings. A bit of flu from bunnings and welded up a heater. Fitting the gal pipe and fittings inside the steel box,...
Finished off the heater. Painted with high temp paint,.....
Gave it a test run yesterday,....
It did work, but all the pipe conections are leaking too much. I stuffed up by not putting pipe sealant on all the joints. With all the heat of the fire, I thought normal pipe sealant wouldn't do the job and would just melt. I actually suspected it would be a problem, but I wasn't worried, because I just thought I'd weld every joint up if there was leaks. In a test run there were leaks, so I did weld up every joint. However I forgot how bad galvanised steel is to weld. It doesn't weld clean, it has bubbles and pops and spits and as I'm not a great welder I couldn't get the joins to be water tight.
I'm also hoping that it will work using the principal of thermosiphon (the pumping action created by rising hot water), so therefore not needing to be pumped. But that also calls for an airtight, water tight seal.
So now I hear there is high temp pipe sealant. Can anyone recommend a pipe sealant that would withstand being inside a fire? Mostly the joints wouldn't get real hot as in theory there is water running though them, however there might be a time when the system is dry and temps could be above 1000 degrees?
The old pipes are no good now, as they've been welded. I've pulled them out and ready to replace with new gal pipe, as soon as I find a pipe sealant that would do the job.
See ya's.
It's great for the kids to have a nice hot soaking in before bed, and then the adults can get in. All good fun. Takes a few hours to heat up 600 litres of water to 40 degrees. '
But I want to do it properly. So I bought some 3 mill steel and some 1 inch gal pipe and fittings. A bit of flu from bunnings and welded up a heater. Fitting the gal pipe and fittings inside the steel box,...
Finished off the heater. Painted with high temp paint,.....
Gave it a test run yesterday,....
It did work, but all the pipe conections are leaking too much. I stuffed up by not putting pipe sealant on all the joints. With all the heat of the fire, I thought normal pipe sealant wouldn't do the job and would just melt. I actually suspected it would be a problem, but I wasn't worried, because I just thought I'd weld every joint up if there was leaks. In a test run there were leaks, so I did weld up every joint. However I forgot how bad galvanised steel is to weld. It doesn't weld clean, it has bubbles and pops and spits and as I'm not a great welder I couldn't get the joins to be water tight.
I'm also hoping that it will work using the principal of thermosiphon (the pumping action created by rising hot water), so therefore not needing to be pumped. But that also calls for an airtight, water tight seal.
So now I hear there is high temp pipe sealant. Can anyone recommend a pipe sealant that would withstand being inside a fire? Mostly the joints wouldn't get real hot as in theory there is water running though them, however there might be a time when the system is dry and temps could be above 1000 degrees?
The old pipes are no good now, as they've been welded. I've pulled them out and ready to replace with new gal pipe, as soon as I find a pipe sealant that would do the job.
See ya's.
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