Propane tank

[rutzbeck]

I have a question about a Propane tank I had filled. I watched the guy fill it. It was empty and he put 4 gallons in. When I picked it up it much lighter than I expected. I mentioned it to him and we looked at the gauge which of course said 4 gallons. I loaded and paid for it. It ran out a lot faster then the last time I used it which was the two weeks before. It lasted 5 days with just the fridge on and the heater ran for probably 2 hours at the most each day. What happened? Do you think his tank was low and he was pumping air?

[lakeside013104]

h45wt wrote:

Old-Biscuit wrote:

A FULL (80%) 20lb propane cylinder IS 4.7 gallons (20 divided by 4.2 equals 4.76)

20lb is where bleeder will spew 'liquid'...which is also where OPD shuts off filling

30lb...7.2 gal (80%)

I don't think you are correct about the 30lb tank. They are about 7 gal capacity so 80% would be 5.6 gals which is where my tanks shut off when filling.

One gallon of liquefied propane weighs 4.24 pounds.

Every DOT certified LPG tank (20 & 30 pounders, there are others, but for this thread we will discuss these) has a water capacity (WC) stamped on the collar of the tank. These tanks are certified to hold 80% of the stamped WC in liquefied propane.

Every manufacture of DOT LPG tanks has a WC number that their type of tank is certified to hold. These numbers may be different for different tank manufactures.

If a particular manufacture's tank has a WC of 25#s than at 80% full of propane, that would be 20#s of LPG. 25#s of water x 80% equals 20#s of LPG.

If a particular manufacture's tank has a WC of 38#s than at 80% full of propane, that would be 30.4#s LPG. 38#s of water x 80% equals 30.4#s of LPG.

Not many LPG dealers fill DOT 20# and 30# tanks by weight any longer. Most just fill until OPD valve shuts off the flow of LPG.

OPD valves are installed in tanks to deliver LPG to the 80% level of volume of WC stamped on the tank.

Sounds confusing, but is not. The amount of LPG put into different tanks can vary according to the certified WC stamped on the coller.

Lakeside

[time2roll]

fishing2 wrote:
If the station fills on a scale the weight of the hose needs to be added to the tare weight.

I think all is connected and the scale is zeroed out. Then the propane flows.

[SidecarFlip]

Kayteg1 wrote:

SidecarFlip wrote:
Propane sells on weight not volume ,,,.

Can you post a picture of such scale?
I've been filling up propane several times a year and all stations I have been to -have flow meter scaled in gallons.

Not sure I can do that in as much as it's not my business and I hunt with the owner (who is fishing right now) but I'll ask him. If I can I can post it. if not, you'll have to take my word for it.

Lakeside will be by in September and I can drive him there and he can see as well (for a collaborating witness) if I cannot.

[fishing2]

If the station fills on a scale the weight of the hose needs to be added to the tare weight.

[time2roll]

My 30 pounders shut off right at 7.0 - 7.2 gallons either by OPD or the bleeder.

[Rubiranch]

SidecarFlip wrote:
Propane sells on weight not volume ,,,.

Kayteg1 wrote:
Can you post a picture of such scale?

its going to have to be a pretty old picture - maybe even a black and white 😉

[h45wt]

Old-Biscuit wrote:

A FULL (80%) 20lb propane cylinder IS 4.7 gallons (20 divided by 4.2 equals 4.76)

20lb is where bleeder will spew 'liquid'...which is also where OPD shuts off filling

30lb...7.2 gal (80%)

I don't think you are correct about the 30lb tank. They are about 7 gal capacity so 80% would be 5.6 gals which is where my tanks shut off when filling.

[Kayteg1]

SidecarFlip wrote:
Propane sells on weight not volume ,,,.

Can you post a picture of such scale?
I've been filling up propane several times a year and all stations I have been to -have flow meter scaled in gallons.

[Rubiranch]

SidecarFlip wrote:
they are bottles not tanks

bottles are made of glass, its a propane cylinder

but who really cares?

[time2roll]

How old is the regulator? Have you performed any leak check?

Maybe he under filled. I would try to assume he put in 4 gallons and you paid for 4 gallons. Go to a real propane dealer and explain your concerns in advance.

[Old-Biscuit]

noxinnhoj wrote:
anyone know how long a tank is good for before re-certs in Canada.I have a 2005 lance with 2 original horizontal tanks

In the USA DOT (Dept of Transportation) has jurisdiction over portable propane cylinders.
Propane TANKS (permanently mounted in Motorhomes) are ASME jurisdiction as outlined by NFPA (National Fire Prevention Association)

In Canada
Portable cylinders must be inspected and requalified every 10 years – it is against the law to fill an outdated cylinder.
The requalification of a cylinder must be done by organizations that have the appropriate equipment, training and certification to do so, and have been certified by Transport Canada to do the work.


Inspection and requalification requirements for TANKS differ by jurisdiction, tank size and tank design.
Tanks are regulated by provincial and territorial authorities.


Yes there are Propane TANKS and then there are Propane CYLINDERS --
not to be confused (mounted/portable)

[noxinnhoj]

anyone know how long a tank is good for before re-certs in Canada.I have a 2005 lance with 2 original horizontal tanks

[lakeside013104]

SidecarFlip wrote:
Propane sells on weight not volume so if he charged you for a 'full bottle (they are bottles not tanks, )tanks are armored vehicles and also hold motor fuel) and it wasn't 80% full, you get screwed.

Typical procedure for a fill from empty is place the bottle on a scale (certified) and zero it and then open the OPD port with a screwdriver and fill it until vapor comes out the port. It's at 80% then. Close the OPD port and charge bu the full weight.

I just filled one of mine, was 10 bucks. Propane is temperature critical too. Filling on a cold day gives you more volume because the product is more dense. Why I fill my 1000 gallon bulk tank (bottle) at the farm, only in the late fall when the ambient is cooler.

Food for thought:

LPG in this day and age is sold from a meter that is temperature compensated, I believe to 65 degrees F.

Lakeside

[SidecarFlip]

Propane sells on weight not volume so if he charged you for a 'full bottle (they are bottles not tanks, )tanks are armored vehicles and also hold motor fuel) and it wasn't 80% full, you get screwed.

Typical procedure for a fill from empty is place the bottle on a scale (certified) and zero it and then open the OPD port with a screwdriver and fill it until vapor comes out the port. It's at 80% then. Close the OPD port and charge bu the full weight.

I just filled one of mine, was 10 bucks. Propane is temperature critical too. Filling on a cold day gives you more volume because the product is more dense. Why I fill my 1000 gallon bulk tank (bottle) at the farm, only in the late fall when the ambient is cooler.