That was quite respectful of you . Thank you kind sir
That must be a hot as day , never seen mine over 60-65. I’ll tell him to raise it up a little . But he runs it outside so if they get set off hell be fine
If you’ve seen it at 60-65psi and that’s normal tank pressure on a hot day then why would you set the prv to the same pressure?
Edit:
Where’s the logic in that?
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Your prv should be 125 psi minimum with straight butane
Your prv should be 250 psi minimum when using propane
These are industry standards
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Yes, that is indeed how that works.
Under what conditions. Nitrogen won’t condense with butane. Butane will freeze before that happens
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You are correct, but Nitrogen still has non-zero solubility in Butane. Think carbonated water.
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I think we are talking about 10E-3 mole fraction at 1 atm N2 approx these temps(50F).
But we are pushing a liquid butane with hundreds of dissolved solutes…who knows.
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…or a nitro charged Guinness. 
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Yes, however butane has an affinity for water, n2 has an affinity to water.
Moisture in your bio mass?
That water forms an azeotrope to n2 and butane
Butane won’t extract water if the temperature is below freezing 0c/32f. Conveniently, it is usually ran below that not bringing them with. Butane is great for fresh frozen
Ethanol, on the other hand. Does have an affinity for water. Which is why it’s a nono for fresh frozen.
We base that off the diameter of the closure on the vessel, if you put a 250 psi relief valve on a 12" spool and your almost double the rating of the closure.
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That is super valuable info, Thank you
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Spool, or clamp rating?
Would closure not include the clamp/lid/spool tho ?
I’m thinking yes from his reply
clamp
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Some vessels expand out and taper back in to a 6" opening. Most cauldrons are far larger than 12" and have a 6" opening, while being rated for propane.
Edit: posted same time as his reply
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True, I didn’t consider that
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A function of temperature and pressure, which the attached phase diagram link demonstrates. Note that in our application, it is primarily used to move gas that has low vapor pressure at subzero temperatures.
Here is a chart showing typical pressure at temperature of butane/propane mixes:
The limiting weak link to most sanitary fitting assemblies is the clamp. Here is a link showing their ratings:
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170psi @ 20c which is usual room temp for me … wow this highlights why in Canada AHJ’s want every bho extractor to have a 250 psi prv
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