LP Tank Heaters

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drizzamed

Active member
Joined
Aug 24, 2021
Posts
28
Location
Texas
Hey peeps! This newbie would like some opinions, ideas, etc on what one does or would/could/should do; if any, on making my 30lb LP tanks efficient during cold weather. I'm looking at a heated electric tank blanket/jacket. May not be as necessary for me as I live near Lake Texoma in North Texas but if this winter is anything like the last, I'd like to be prepared!
 
You have nothing to worry about. Propane works fine until you're WELL below zero degrees F.

If I remember right, in Fairbanks Alaska we didn't turn on the tank heaters until it got down to -30F. Even then that was for the tanks that were in open air. The tanks that were underground or enclosed were good lower than that.
 
Thanks for the info! What made me think of this was I used to have my CO2 tank inside my kegerator so even at like 40 degrees it was losing a lot of efficiency.
 
I learned something and got a chuckle!
While propane has a very low temperature of vaporization, it does slow at lower temperatures so here’s the story.

The freezing point of propane is -44 degrees Fahrenheit. The coldest temperature recorded in east Texas is -8˚F. So there’s not much reason to be concerned about your propane freezing.

While it’s unlikely your propane will freeze, it can still be affected by very cold temperatures. Propane contracts when it’s cold. When it’s extremely cold outside, the volume of propane inside your propane tank will shrink, which creates a loss of pressure. The problem is, if the pressure becomes too low, the propane inside your tank will not be able to reach your gas burner. That means you may not be able to run your propane appliances, including your furnace or water heater, which can be very problematic in severe cold.

That’s why you should know what to do the next time Old Man Winter comes to call. Keep your propane tank at least 30% full because the more propane in your tank, the more positive pressure there is. If very cold weather is in the forecast, check your propane tank gauge and fill it if near empty. If possible keep the propane where sun will strike the tanks to help with vaporization.
 
Your tank won't freeze, but the rate of evaporation slows substantially and some RVers have reported problems at temperatures near zero. The rate at 0 F is about 30% of the rate at 70 F. Appliances that demand a high volume of gas may suffer a bit if the evaporation rate gets low (the furnace & water heater are examples).

A not-unusual problem is LP gas that contains a percentage of butane instead of propane. Butane has a higher boil point, so it performs better in hot climates but more poorly in the cold. If you filled your tanks in a hot climate and later go to a cold place, you may experience a problem.

The regulator can also chill below ambient, due to the venturi effect of the gas rushing through it. The regulator can freeze up even though the tank is still ok. Wrapping the regulator with some insulation might avoid a problem.

They make inexpensive blankets for wrapping DOT LP bottles. Not a heater - just insulating. Might help avoid problems. https://www.amazon.com/Ventilated-Propane-Protector-Standard-Cylinder/dp/B0872C7BXM/
 
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typically 90% or more pure propane
Right, but "typical" doesn't mean universal. Propane bottled in hotter climates is sometimes a much higher percentage of butane. Snowbirds who fill their tank in Florida can sometimes get surprised when they head back north and encounter much colder weather.

That said, 90% propane is "close enough" to avoid the butane freeze-up possibility.
 
IN texas so long as you have PROPANE in the tank and not Butane you should not have a problem.
A heat lamp set oh say 5 feet off may help if you get nailed by a Butane as propane dealer. They do exist south of the mason dixon line and if you find one be sure to report him.

What's the difference?
Butane is actually the better fuel most of the time as it burns a few degrees hotter but. The boiling point of Butane is rather close to the boiling point of water (30.2°F) propane is closer ot the point (-40) where you don't need to add the C or F) (-43.6°F)

So if it's say 20 out. Butane is liquid and does you no good at all. Propane on the other hand still vaporizes and burns. Now if you are getting close to that F/C cross over.. Propane many not generate enough pressure... but if it's that cold in texas. we are in DEEP TROUBLE.
 
As hinted earlier in this thread consumption rate also matters, though as long as you are only running a propane furnace and a water heater things should not be too bad in north Texas, that is as long as you are not trying to heat the interior to Sauna temperatures. If you add a propane fueled generator to the mix all bets are off.
 
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