This is interesting. How do you know they are 76?
How much air does an LP85 hold at 2400 PSI?
- Thread starter CaveSloth
- Start date
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OP
CaveSloth
Contributor
When I bought them I was told they were LP85s. After this thread I’m not so sure.
OP
CaveSloth
Contributor
Next time I have them filled I will find out how many cf goes in vs the psi increase and calculate what they hold at 2640.
runsongas
Contributor
the old lp76 and the newer lp85 are very similar because the old lp76 was quoted at 2400 psi (and didn't come with a plus rating from the factory).
How will you know how many cuft are going in? That usually requires measuring pressures and knowing the tank size. Vicious circle.
OP
CaveSloth
Contributor
Cowfish Aesthetic
Contributor
OP
CaveSloth
Contributor
I mean they charge me by the cf so I hope they know how much they gave me.
Gas is a liquid, easy to measure volume.
They do NOT know how many cuft you got without knowing your tank size and working pressure. They measure pressure at beginning and end of fill, then calculate (P(end) - P(start))/2640 * 85. They know the working pressure from the stamping on the tank, but have to guess at tank size....like everybody on this thread is doing. 85 is a very good guess, but I would not bet my house on it.
OP
CaveSloth
Contributor
Wow. Ok well then I guess I’ll start telling them I have an LP76 and save some money since it seems the tank size can’t actually be determined.
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