Looking to install a new tank to replace my old 20 lb steel tank with a fiberglass one from Defender but confused about sizing
LPG Tank
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look at a camping supply store for the tank, cheaper...
As far as I know, a 20lb tank in steel and fiberglass should be the same size.
As far as I know, a 20lb tank in steel and fiberglass should be the same size.
Hi ROBFMCC....The tanks are not the same size or weight this is why I wanted to know capacities nad camping sores do not generally sell fiberglass 20LB tanks
The last time I looked a 20 pound size tank would hold 20 pounds of propane without regard to the tank material. Steel tanks are quite heavy and aluminum tanks are lighter and the fiberglass tank may be lighter still but they will have the same capacity if they are all 20 pound size tanks.
A 20 lb tank will hold 25 lb of propane in liquid form, but is restricted to 80%, hence the 20 lb rating.
Look for a "WC" number - that stands for Water Capacity, and is the weight of water it can contain when filled to the top. Liquid propane is just a shade over 1/2 the density of water (I think it's .525, but I can't swear to it), so for close-enough numbers, divide the WC number by 2, then take 80% for the capacity in pounds of propane. Same is true for little tanks, like the 4 pounders my last boat had.
Empty weight of the tank is stamped onto the collar as "TW" for Tare Weight. A full (80%) 20 lb tank should weigh the Tare Weight plus 20 lb.
I haven't looked at fiberglass tanks, but I would imagine they are required to have the same info on them somewhere.
Look for a "WC" number - that stands for Water Capacity, and is the weight of water it can contain when filled to the top. Liquid propane is just a shade over 1/2 the density of water (I think it's .525, but I can't swear to it), so for close-enough numbers, divide the WC number by 2, then take 80% for the capacity in pounds of propane. Same is true for little tanks, like the 4 pounders my last boat had.
Empty weight of the tank is stamped onto the collar as "TW" for Tare Weight. A full (80%) 20 lb tank should weigh the Tare Weight plus 20 lb.
I haven't looked at fiberglass tanks, but I would imagine they are required to have the same info on them somewhere.
Actually we only get about 4.5 gallons in the new tanks because of the OPD. Then half the time the damn OPD jams and we have to beat the tank on the ground to get the LPG to flow.
Life was much simpler in the old days.
Life was much simpler in the old days.
I should add that the rule of thumb is that the cylinder capacity is 42% of the WC figure, which includes the 80% limit, as well as the density ratio of propane to water.
Makes it easy to do the math. Multiply WC by .42 for actual propane capacity in pounds.
And yes, those OPD's can be a pain. So can propane dealers who set their scales up without allowing for the weight of the hose - take your newly filled cylinder home, weigh it, and see how close it comes to the .42 x WC + TW figure. :Liar: If they're selling you 20 lb, you should be getting 20 lb. Those exchange services commonly sell you less than 20 lb, which is ok if they tell you how much you're getting, but I don't think many go out of their way to tell you you're getting 16 pounds (for instance).
Of course, with a lightweight aluminium or fiberglass cylinder, the OPD should close it off before the scale tips, but I guess that depends on how close your dealer is paying attention. You may actually get the full amount, if the OPD doesn't close too soon.
Makes it easy to do the math. Multiply WC by .42 for actual propane capacity in pounds.
And yes, those OPD's can be a pain. So can propane dealers who set their scales up without allowing for the weight of the hose - take your newly filled cylinder home, weigh it, and see how close it comes to the .42 x WC + TW figure. :Liar: If they're selling you 20 lb, you should be getting 20 lb. Those exchange services commonly sell you less than 20 lb, which is ok if they tell you how much you're getting, but I don't think many go out of their way to tell you you're getting 16 pounds (for instance).
Of course, with a lightweight aluminium or fiberglass cylinder, the OPD should close it off before the scale tips, but I guess that depends on how close your dealer is paying attention. You may actually get the full amount, if the OPD doesn't close too soon.
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