Lp tank freeze up

[Scheinin]

I am wintering in Maryland. This last 3 weeks average night temperature is 20 degrees. We have 2 30 LP tanks, but because we are using so much propane for heat, we got a 100 pound LP tank, which sits outside our RV. None of my tanks have frozen. I doubt it is the temperature affecting your tanks.

[B and B]

Originally Posted by NJKris

Desert Boat I think has the best answer for now. New tanks are sometimes pre-purged, but not all. Moisture plus air in an unpurged tank will cause these problems, as well as low propane levels when it's cold. 45 degrees is not cold, merely chilly! I bbq all the time on my gas grill below 32, nothing freezes but me!

I was BBQ last here in the Great White North at 0 F and nothing froze up.

[Pred]

Forgot to mention all my propane tanks gets filled at Costco. Next time I'm there I will be sure to ask if they know about the blending.

[B and B]

Originally Posted by NJKris

Interesting about the blending. Didn't know they had a Southern blend.

Found that out in Florida in 1971. Returning home in OhiO the furnace stopped working after ice formed in the propane lines. Was Butane. My Father vented the tanks and refilled with propane and all was well after.

[NJKris]

B and B!!!! Good to see you again! I have something for you:

https://www.youtube.com/watch?v=dN3w...ature=youtu.be

[Pred]

Originally Posted by Pred

Forgot to mention all my propane tanks gets filled at Costco. Next time I'm there I will be sure to ask if they know about the blending.

Just asked the Costco propane guy today about blending with butane and he did confirm. Also said Amerigas is their supplier and the price did go up 20 cents a gallon. Things are getting back to normal for the most part.
My question now is how far north do you have to go to get the good stuff with no "blending"? Anyone know? I'll be making a trip to Oklahoma and will ask what kind of propane they have.

[NJKris]

Butane stops vaporizing at it's boiling point of 31 deg F. I would think that any region where it's probable to have temps this cold sustained (enough time for entire tank to reach that temperature) would not be feasible for blending. I imagine only the deep South can get away with blending.


I'm thinking the percentage has a LOT to do with it. If only a small percentage of the LP was butane, that part of the liquid would remain liquid, but there would be adequate pressure from the boiling propane. As the proportion of butane to propane increases, so would the vapor pressure decrease.

[Scrapper]

Originally Posted by NJKris

Desert Boat I think has the best answer for now. New tanks are sometimes pre-purged, but not all. Moisture plus air in an unpurged tank will cause these problems, as well as low propane levels when it's cold. 45 degrees is not cold, merely chilly! I bbq all the time on my gas grill below 32, nothing freezes but me!

It's about time you tried on one of those Warm Guard's jeff64 mentioned.

[NJKris]

Does it come in size 50? lol.

[david_reaves]

I'm throwing in my two-cents with the issue being butane in the LPG mix. I've had issues with tanks filled in central Texas going with me to Colorado in the winter and vapor pressure falling off to unusable with the tank still almost a third-full. The easy fix for 20lb tanks is to take the partial (unusable) tank to an exchange in the cold area. It will have pure propane and will be fine in colder temperatures. Just be sure that you get a tank that has a build date that is at least as new as the tank you are giving up. If you have larger tanks, or a built-in tank in a vehicle you will have to have the propane supplier purge the tank, then refill with pure propane.

[Hawksclaw]

I worked in a major refinery in the south for 30 years. The last 14 years I was an operator on a propane unit. We took propane produced in the refinery and cleaned it up, dried it to commercial specifications. Then put it in the pipeline where it was stored in salt domes or pumped to commercial storage facilities. Propane had to be dry to less them 10 parts per million moisture content and was 90 plus percent pure propane. Most of the time it was 93-95% propane with butane, iso butane etc making up the rest of the volume. The only thing we didn’t didn’t add was methyl mercaptan to give it the stench so you can detect a leak. That was some at the storage facility. The moisture spec was to keep it from freezing in the orfice of the stoves heaters etc.

[Celticrider]

Hard to imagine propane freezing at +45,no matter what the issue.
Just not cold enough, even if not 100%propne.
We BBQ here in Ontario many times in winter to -18C/0F with never any issues
Obviously another issue

[garywilson]

I live in Texas.
Used to have butane till 'they' quit selling it. The tank had to be underground to prevent freezing.
With Propane, the only thing I've had freeze up is moisture in the regulator.
Put on new regulator, end of issue.
45 degrees outside plus cooling of the propane would probably freeze the regulator if there is moisture in it.

[saltchuk]

I worked for many years in an oil refinery. We tested propane and butane for purity by measuring the boiling point of the liquid in a flask at atmospheric pressure.

Propane would be boiling away, turning into a gas at around -40 degrees F.

Likewise butane boils at around +30 degrees F.

Raising the pressure raises the boiling point, but a regulator operates at low pressure.

I live in BC, Canada and we only have propane to use in our tanks. However, when I was in the California desert ( pre-covid ) I was able to get butane, cheaper but with more heat energy per gallon, in the same way that heavier diesel has more energy than gasoline. I topped up with propane when I returned to Canada.

Butane was used mainly in gasoline blending.

I think the tank contains far too much butane to be used in the winter.

There was a comment about the possibility of moisture being in a new tank. IPA or isopropyl alcohol can be used in an empty tank to dry it out. Water will mix with the alcohol and then the contents can be poured out to dry the tank properly.

[travelingeast416]

How would we know if the gas is a blend? Is it posted somewhere? I have trouble with my large BBQ cooker where some tanks stop flowing, while others at the same time run until empty.. I was told the safety valve in the tank was sticking.

[NJKris]

Originally Posted by travelingeast416

How would we know if the gas is a blend? Is it posted somewhere? I have trouble with my large BBQ cooker where some tanks stop flowing, while others at the same time run until empty.. I was told the safety valve in the tank was sticking.

Don't know about blending recipe posts, like they have on gas pumps. Could be safety valve sticking as you said. Make sure you open propane valve slowly and of course burner knobs off or you can trigger the throttle down safety. Any big rush of propane out can trigger safety, like a decent leak, or all burners turned on at once.

[NJKris]

Originally Posted by travelingeast416

How would we know if the gas is a blend? Is it posted somewhere? I have trouble with my large BBQ cooker where some tanks stop flowing, while others at the same time run until empty.. I was told the safety valve in the tank was sticking.

Originally Posted by Celticrider

Hard to imagine propane freezing at +45,no matter what the issue.
Just not cold enough, even if not 100%propne.
We BBQ here in Ontario many times in winter to -18C/0F with never any issues
Obviously another issue

GaryWilson got it right, when LP boils to give off gas, it is endothermic, which means it is absorbing heat. So it's not giving off heat as it boils like water does, it's absorbing heat, so things frost up, possibly even at regulator. So minute amounts of moisture can crystallize and block flow through tiny orifices.