Temperature affect on propane meter

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homedepotpro
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Wed Nov 21, 2007 11:58 pm

As many of you know the weather is changing and the air is getting colder. I would still like to shoot my advance comb., but im not sure if/how to account the the temperature's affect on the propane. My logic says lower temp, lower vapor pressure, that means less psi it the meter to get the same amount of gas, but i don't really know. I was wondering if i could get some help, im looking for a table, some equations or maybe just some educated estimates.

thanks
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hi
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Thu Nov 22, 2007 12:05 am

thats true, but you are forgetting something, the air it self...

the air will condense as well as the propane, so you wont have to change anything. thats my theory...
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote

you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
SpudBlaster15
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Thu Nov 22, 2007 12:43 am

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Last edited by SpudBlaster15 on Wed Jul 14, 2021 6:02 pm, edited 1 time in total.
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homedepotpro
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Thu Nov 22, 2007 12:44 am

yeah hi, but im pretty sure they don't condense at the same rate. at 0*F propane's vapor pressure is 11psi and oxygen is, idk, way the hell up there
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SpudBlaster15
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Thu Nov 22, 2007 2:14 am

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras nec placerat erat. Vivamus dapibus egestas nunc, at eleifend neque. Suspendisse potenti. Sed dictum lacus eu nisl pretium vehicula. Ut faucibus hendrerit nisi. Integer ultricies orci eu ultrices malesuada. Fusce id mauris risus. Suspendisse finibus ligula et nisl rutrum efficitur. Vestibulum posuere erat pellentesque ornare venenatis. Integer commodo fermentum tortor in pharetra. Proin scelerisque consectetur posuere. Vestibulum molestie augue ac nibh feugiat scelerisque. Sed aliquet a nunc in mattis.
Last edited by SpudBlaster15 on Wed Jul 14, 2021 6:02 pm, edited 1 time in total.
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psycix
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Thu Nov 22, 2007 9:10 am

Its still the same 4.2%, but yes, there is more fuel in your meter, aswell, more oxygen in your chamber.
Thats why combustion cannons are said to have more power in cold weather (but your pvc gets brittle!)
When temperature get VERY cold, you might have your propane turning liquid when exceeding the vapor pressure.
Then you should have OR a bigger meter, or measure two shots with only half amount of the fuel (and thus pressure).
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homedepotpro
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Thu Nov 22, 2007 10:41 am

thank you spudblaster, you are a very knowledgeable spudgunner.
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