Propane weight

how cold was it when you filled the tank, it does make a difference!

For a quick and dirty -- and assuming that this is a 30 pound cylinder -- do this:

1. Check the collar of the cylinder. You'll find "TW" followed by a number. That number is the tare (empty) weight of your cylinder.

2. Add the TW to 30. This will yield the weight of the cylinder when it is full of propane.

3. Put the cylinder onto your bathroom scale. It should read pretty close to the full weight established above, assuming that your bathroom scale is relatively accurate.

If the cylinder weighs more than what you'd expect, then it could be that your filler incorrectly relied on the OPD valve to fill the cylinder, and the OPD is bad. (Because OPDs are never inspected again after initial installation, fillers are not supposed to rely on them as a means to decide when to stop filling a cylinder.)

:)
Lynn

pigman1 wrote:
If you think his equipment is faulty, file a formal complaint with your state's Weights and Measures. They have to get their equipment certified as does everyone selling measured quantities of a product, and a complaint will be sure your dispenser gets a good look next time it's his turn. Also, to be sure your OPD on your tank is not malfunctioning, put it on a scale. Full weight is stamped on the bottle neck.

Good point... I did not watch the operator fill the tank, I had gone into the office to pay. Told the clerk a 30 lb / 7.1 gal... she op to wait for the fill guy to come in and say how many gallons. When he said 7.8 gallons I commented about thinking 7.1 was all that could be added to that size tank... he stated, "if filled slow more gas could be put in the tank". Think I'll take the tank back tomarrow and have them reweigh it. I do not want to travel with a defective or overfilled tank... Thanks for the suggestions.

noplace2 wrote:
This is a no-brainer. Tell the filler to stop it at 7 gallons with an empty 30lb tank and make sure he/she isn't "venting" while filling. It is absolutely unnecessary. You might get a dirty look because a few of them are used to pumping significantly more while they're "venting" the tank. $$ in the bank not yours.

I'm certified to dispense propane in 11 states. I know of what I speak.

Had someone fill one of mine while on vacation. He "vented" the tank. When I got it back to the camper, it would not work until I used some of the propane from the tank (used it on the grill)

If you think his equipment is faulty, file a formal complaint with your state's Weights and Measures. They have to get their equipment certified as does everyone selling measured quantities of a product, and a complaint will be sure your dispenser gets a good look next time it's his turn. Also, to be sure your OPD on your tank is not malfunctioning, put it on a scale. Full weight is stamped on the bottle neck.

This is a no-brainer. Tell the filler to stop it at 7 gallons with an empty 30lb tank and make sure he/she isn't "venting" while filling. It is absolutely unnecessary. You might get a dirty look because a few of them are used to pumping significantly more while they're "venting" the tank. $$ in the bank not yours.

I'm certified to dispense propane in 11 states. I know of what I speak.

Propane weighs 4.2# per gallon (at 60*F)

30# cylinder full is 7.14 gallons (Full IS 80% of cylinder)

I have had 'meters' register 7.1, 7.3 & 7.5 when being refilled using a 'gallon meter'

Proper method is by 'weight'
Cylinder placed on scale ----set for cylinder weight (on collar----typically 25-28#) plus 30# (55#---58#)

Best method......weight (on scale) PLUS bleed screw open.
When liquid spurts done. Scale should trip


The propane guys meter is OFF.........cause the cylinder OPD should not have allowed continue filling beyond 80% (30#---7.1 gallon)
That's what the OPD is for......float raises up with liquid level and set to shut off inlet valve at 80% level.

OR

YOUR OPD IS FAULTY (my bet is his equipment. It's to his benefit)

Temperature effects density and cold propane is more dense. The 4.2 lbs/gallon is at ISO standard temp (15°C/59°F).

It should be about 7.1 gallons. Looked it up.