10 REASONS NOT TO BUY VIKING PROPANE CYLINDERS.

[Jammer]

Originally Posted by Americanrancher

For some reason some people on this forum seem to think that this is dangerous, it ISN'T. It is no different than a fill at a station just slower.

The three hazards are: 1) Frostbite, 2) Fire/explosion, and 3) an overfilled cylinder.

Frostbite injuries from propane occur every year in the USA and are sometimes serious, particularly where injury to the eye is involved. The usual modality is disconnection of high-pressure propane lines where liquid propane has accumulated or condensed in the lines. Less often a hose bursts either just from the pressure or because someone left a hose full of liquid connected with valves closed at both ends, then sun or rising temperatures caused the liquid to expand.

Fill stations mitigate these risks by placing the fill valve as close as possible to the cylinder being filled, and installing relief valves in any sections of line that can be valved off. They also use hose that is rated for propane use. Propane is a solvent that causes rubber hoses to deteriorate internally while still looking OK on the outside. Propane fill operators ordinarily do wear gloves, in my experience, some also wear eye protection.

The hazard from fire/explosion due to leaks is self-explanatory except for the fact that propane fill stations are sited in open areas without low spots where gas can accumulate.

The hazard from overfilled cylinders is that the relief valve will open when the cylinder is subjected to higher temperatures than the temperature at which it was filled. The OPD will not prevent this during transfilling operations, and the only reliable way to prevent it is to weigh the tank with an accurate scale during the fill.

I have transfilled cylinders, too, sometimes it's the best way. It cannot be done safely without understanding the hazards. Use the right kind of hose. Transfill away from the boat and away from low areas and ignition sources. Wear gloves and a long sleeve shirt. Wear eye protection. Weigh the cylinder you're filling. Use care when bleeding the hose.

When I'm old I want to be out cruising rather than learning to read braille with one hand.

[billcrowley]

wyb2 - I have always used a bathroom scale to determine the remaining propane in my steel tanks, which weigh around 18 pounds when empty.

[Mickeyrouse]

Originally Posted by landsend

Lol.
But you still use diesel fuel, the nastiest of fossil fuels!!

Nasty, yes. But nastier than gasoline? Or jet fuel? Or coal?

Admittedly it’s a competition of evil.

[wyb2]

Originally Posted by billcrowley

wyb2 - I have always used a bathroom scale to determine the remaining propane in my steel tanks, which weigh around 18 pounds when empty.

Sure, that works. As long as you are home, or carry a scale with you.

Still seems highly preferable to just look at the composite tank (which weighs around 10 lbs empty) and know immediately. No trick, no process, just look at it.

[wyb2]

Originally Posted by Jammer

…

The hazard from overfilled cylinders is that the relief valve will open when the cylinder is subjected to higher temperatures than the temperature at which it was filled. The OPD will not prevent this during transfilling operations, and the only reliable way to prevent it is to weigh the tank with an accurate scale during the fill.
…

Can you explain this a little more? Doesn’t the tank have an over fill prevention device (OFD) and an over pressure prevention device (OPD)?

How does transferring from another tank defeat either of these?

Edit: Looks like I was making a bad assumption on the acronym. General point of the question still stands.

[Shaneesprit]

I am happy to say the UK Calor Gas has reversed their decision to discontinue 3.8kg propane bottles. (Exchange so no worries over how old your bottle is, as you never get the same bottle back).
These are very common in the UK and if you like me are using this bottle it’s unlikely you have room for the larger bottles, without major modifications.

[Jammer]

Originally Posted by wyb2

Can you explain this a little more? Doesn’t the tank have an over fill prevention device (OFD) and an over pressure prevention device (OPD)?

How does transferring from another tank defeat either of these?

Transfilling is an inherently slow process -- typically you hook up the cylinders and then do something else for half an hour or so.


The OPD (overfill prevention device) valves, by design, don't close completely. If they did, there would be no way to utilize the propane in the cylinder once the OPD tripped as there is no one-way valve or ball check. When cylinders are commercially filled, a pump is used and propane enters the cylinder at several GPM (maybe 2-3, guessing) and there is a flowmeter with a totalizer that shows the amount of propane being dispensed. Therefore, it is obvious when the OPD has tripped, and the operator, even if being sloppy, shuts off the pump.


But if transfilling at a slow rate it is not at all clear that the OPD has tripped and liquid propane will continue to flow at a sufficient rate to fill the tank completely, with no head space. I have had this happen -- it's not hypothetical.


The overpressure devices (relief valves) are reliable and do work but the result is that flammable gas vents out the relief valve leading to a fire and explosion risk. It's the lesser evil given that the cylinder would otherwise rupture. The reason the OPDs were mandated 30 years ago was the growing number of exactly these sorts of incidents -- most commonly, an overfilled cylinder would be placed in the trunk of someone's car, where it warmed up, the relief valve vented, and the car exploded as soon as there was a source of ignition.

[wyb2]

It’s rate dependent, that makes sense.

[wsmurdoch]

But, one need not depend on the overfill protection device to indicate that the upright cylinder being filled is actually full. Simply crack the screwdriver operated bleeder valve on the side of a US propane cylinder valve and watch the escaping propane (glasses & gloves, no flames). When the level on the liquid reaches the end of the dip tube in the tank, the discharge will change from gas to liquid. It is easy to see. (The length of the dip tube in inches is the number following the DT stamped on the tank collar.)

Scales work too.

[Mexican Hat]

Thanks to those who made contributions to the thread. I have a family emergency and have to leave the boat for a couple of weeks. Viking propane tanks are not going to be addressed until I return. I will post results on my quest for a testing facility.


And as I was able to book flights that excluded Boeing aircraft, there's a good chance I will return... I

[CruisePriest]

Disposal is also quite difficult because of the explosive residue potential.