Jump to content

Butane Boiling Point


Pete

Recommended Posts

As I understand it butane boils at about zero centrigrade. Lower than zero it remains a liquid and non of your gas appliances will work.

 

To get butane to zero centrigrade what typically will the outside temperature need to be?

 

The reason I ask is that we have been out in our caravan at temperatures low enough to freeze the water in our pipes but not have any impact on our butane.

I am assuming that the front locker and the gas cylinder provided sufficient insulation to prevent the butane reaching zero centrigrade. Our water pipes, on our previous van ran underneath the floor rather than inside so would freeze quite easily.

 

We were away 2 weeks ago and temperatures just fell to freezing and we had no problems. Our next trip is to Scotland in 10 days. The long range weather forecast shows no frost so at the moment I don't think I'll change to propane.

 

I would be interested to hear from anyone who has 'lost' their butane due to the cold especially if they can remember how cold it was.

 

 

Pete. :)

Link to comment
Share on other sites

We have had the misfortune in the past to have had the Butane freeze, now we have changed over to propane. Normally the front locker will provide some insulation against the outside freezing temperature, but there is nothing worse than waking up on a cold winters morning and finding your gas is frozen and you cant have a cuppa. For winter use I would always recommend propane. If you have to use Butane wrap some insulation around the cylinder.

For our water canisters I bought a cold water tank jacket from Wickes DIY and wrap it around the container holding it in place with some Duck tape. It only cost £3 and hasn't let us down. I also get an old cardboard box which I flatten and stand the water container on it.

Link to comment
Share on other sites

But it does specify "at atmospheric pressure"

 

Therefore, the temperatures are not accurate boiling points for the LPG, propane or butane, at the pressure in the cylinder.

 

Also, I wish these "experts" would check their information.

 

The text says butane boils at 0. 6 degrees C but the chart quotes 9 degrees C.

 

Not very reassuring, to say the least.

You can not reason with an unreasonable person.

Link to comment
Share on other sites

I could give you the five dollar answer (and witter about triple points, specific heats, and azeotropes) but it wouldn't do much good.

 

Absolutely pure butane will freeze at 0. 6 Celsius. But the stuff in the bottle isn't "absolutely" pure. Besides, even solid butane has a significant vapour pressure i. e. it sublimes (goes straight from a solid to a gas).

 

The physical chemistry is complex, but you need to get butane really cold before it produces no vapour at all; at "normal" temperatures you have a liquid in equilibrium withi its vapour.

 

If you really want it I will post URLs to some chemistry sites that explain all the math.

Link to comment
Share on other sites

Its getting too technical for me,

So here's my twopenneth, if its winter use propane, if its summer use butane (if you must)

 

I have an inline connector, so swapping is not a problem, I used butane this year (for the first time), but for the life of me cannot see the benefits over using propane all year round.

 

A few years ago we went on a bonfire rally near Doncaster it was -5 on the Saturday night, and that's when the folk with butane new why we had propane :)

 

Paul

Paul B

. .......Mondeo Estate & Elddis Avanté 505 (Tobago)

Link to comment
Share on other sites

I could give you the five dollar answer (and witter about triple points, specific heats, and azeotropes) but it wouldn't do much good.

 

Absolutely pure butane will freeze at 0. 6 Celsius. But the stuff in the bottle isn't "absolutely" pure. Besides, even solid butane has a significant vapour pressure i. e. it sublimes (goes straight from a solid to a gas).

 

The physical chemistry is complex, but you need to get butane really cold before it produces no vapour at all; at "normal" temperatures you have a liquid in equilibrium withi its vapour.

 

If you really want it I will post URLs to some chemistry sites that explain all the math.

13381[/snapback]

 

 

Hi Eighthof seven

 

All I'm really after is an idea of what the outside temperature will be when butane won't work. From a later post by Paul_B he has indicated -5. Any advances?

 

I guess that butane is more efficient than propane (ie you use less for the same amount of heat) otherwise we would always use propane.

 

 

Pete.

Link to comment
Share on other sites

Hi Eighthof seven

 

All I'm really after is an idea of what the outside temperature will be when butane won't work. From a later post by Paul_B he has indicated -5. Any advances?

 

I guess that butane is more efficient than propane (ie you use less for the same amount of heat) otherwise we would always use propane.

Pete.

13413[/snapback]

 

Ooo! We been down this alley before. Propane has a higher calorific value than propane but (and there are loads of buts) nobody has yet come up with a definitive answer on which it is best to use. At the moment I can buy a 7kg butane cheaper than a 6kg propane - but I still don't know if it's cheaper to run.

 

Incidentally, if you insulate the gas cylinder well enough, you won't get any gas out as it draws heat from the atmosphere to gassify it.

 

 

 

Mike

Link to comment
Share on other sites

Guest Hobbybod

Sorry if a bit late on this one; been away at the NEC!!

 

It's a bit more complicated than just stating the boiling point (not freezing point) of the gases.

 

In order to get gas in the cylinder, and into the 'van's appliances, the liquid butane must boil. To do this it must obviously be above the boiling point of ~0. 5 degrees C.

 

BUT, when Butane gas is taken from the cylinder it cools the remaining liquid butane down; the greater the gas 'take-off' the greater the cooling effect. So you must never put an insulating jacket round a gas cylinder in the mistaken idea of keeping it warm. Heat from outside needs to get into the cylinder.

 

Now if there is insufficient heat getting into the cylinder, because it's cold outside, then the liquid butane will cool down to below it's boiling point and you'll get no gas. This is of course a gradual process, but it does mean that if you are using a fair bit of gas to heat and cook, then it may only be 5-6 degrees outside when the gas starts to fail to boil off. I know; it's happened to me in mid-breakfast!!

Link to comment
Share on other sites

Hobbybod's explanation seems to fit my observation that butane ceases to be effective somewhere between +5 and 0 degrees. If there was a frost overnight, butane wouldn't work until the sun had warmed things up a bit. An excuse for a lie in!

 

As far as I can see, butane is slightly cheaper to run, taking into account the different calorific values and different regulator pressures (on pre-2004 caravans). This is the justification for changing back to butane in the spring - but only if you use quite a bit of gas.

 

I've changed permanently - I don't change back as a 3. 9kg propane lasts a full year.

Link to comment
Share on other sites

Butane is used during the summer because it has a higher calorific value than Propane.

Like Paul said Butane in the summer B)  Propane in the winter :o (that is if your mad enough to go caravanning in the winter).

 

Mike.

13409[/snapback]

 

. ..or mad enough to keep changing over.

 

PS winter caravanning is great - all the sites that are open to ourselves and others of a like mind. Children are not so prevalent either (if that is your preference)!

Link to comment
Share on other sites

I suppose the most important question will be is, is it going to be above freezing when you are there. You could ask a weather man, or if you are really feeling lucky use butane anyhow.

 

Inline connectors about a tener, swap from butane to propane about ten seconds, I use them when swapping from awning heater, with spare bottle back to van etc.

 

price difference between butane and propane for a week, less than the price of a pint, :o

 

Breakfast when you want it priceless. :D

 

Paul

Paul B

. .......Mondeo Estate & Elddis Avanté 505 (Tobago)

Link to comment
Share on other sites

:blink: After using my caravan every week this year, I can tell you that Propane is the lifesaver.

2 mornings on the trot in early March, I had Butane which had frozen. I had no hot water, no heating and no cuppa (no electric on this field)

 

Changed to Propane after that, and never looked back. Only problem is constantly swapping the 6kg bottles. ....dont want a big one as I would look like a resident rather than caravanner!

Link to comment
Share on other sites

I have just come back from marshalling at a motor cycle practise day on the Welsh coast. Last night it dropped to about -4 C.

 

I had a knock on my door this morning about 7ish by my uncle who was also there. Could I boil the kettle for him as his gas would not work. There fire, hot water heater and fridge had also cut out during the night.

 

I said it was not problem, but would just finish drying after my nice hot shower!

 

They will be chaning to propane soon, it might cost a bit more, but whats the point of having cheaper gas if youcannot use it?

 

Trevor

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...