Butane at low temperature

[Deleted member 13519]

Hi
I've been lurking for a while on here and finally need to post - sorry it's a question!

I'm new to the whole camping scene and only got van a few months back.

I recently found out that butane (blue bottles) stop working properly at about 4 degrees C and that propane (red bottles) are better for low temperatures but that propane costs more in the long run.

How easy is it to swap between butane and propane and would it be worth having a bottle of each?

Thanks for any help

 

[Canalsman]

Butane and propane require different regulators, because they operate at different pressures.

So to use a dual system you would need two separate feed circuits, and a switchover valve of some type to prevent both being used at the same time.

Alternatively you could physically disconnect the butane system and connect propane, or vice versa.

Too much fuss and bother if you ask me. And do you have sufficient space to accommodate both?

I am about to change over from butane to propane for keeps. I can't believe that the costs are that significantly different if you're using relatively small amounts of gas.

 

[Deleted member 13519]

Thanks for your reply.

It would really be a summer/winter switch over so disconnecting and reconnecting wouldn't be much of an issue.
Also yes the gas locker has room for 2 bottles which are both connected.

So is a different regulator all that is required? Ie. will the appliances be ok with either type of gas?

 

[Poco Loco]

Regulator

Hi
I've been lurking for a while on here and finally need to post - sorry it's a question!

I'm new to the whole camping scene and only got van a few months back.

I recently found out that butane (blue bottles) stop working properly at about 4 degrees C and that propane (red bottles) are better for low temperatures but that propane costs more in the long run.

How easy is it to swap between butane and propane and would it be worth having a bottle of each?

I'm sure the guys on here will guide you as they have excellent knowledge. However, I believe that all you need to do is change the bottle and regulator. To ensure you have a good seal when you change the regulator over you can buy fancy fluid that you put around the pipe connection to ensure it is ok. If it leaks you get big bubbles blowing up when you turn on the gas. I'm sure someone may suggest water and washing up liquid.

As for cost I'm sure for the few minutes it takes to swap them over it's worth having winter and summer bottles.

Hope this helps

 

[David & Ann]

Thanks for your reply.

It would really be a summer/winter switch over so disconnecting and reconnecting wouldn't be much of an issue.
Also yes the gas locker has room for 2 bottles which are both connected.

So is a different regulator all that is required? Ie. will the appliances be ok with either type of gas?

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YES, the advice given is correct. I run a German and Spainish bottle from the same connector. The Spainish connector is a German pipe where I have cut off one end of the pipe and fixed a Spainish adapter which locks onto the bottle. One bottle is shut down when I use the other. I admit I do not have a regulator on the Spainish bottle. Not correct, but I know what I am doing. No problems in 51 years on the road.

 

[jezport]

Propane and butane can be used at the same regulator (30mbr) The way it can be done is by fitting a 30mbr bulkhead regulator which is now the standard on motorhomes since 2004. Then you can either have a change over valve with one pigtail for the butane and the other for propane. Or just the 2 pigtails and swap them when required.

You must check the specification on your appliances to see that they are set to run at 30mbr. Some older mainly foreign vans can have appliances set up to run only on 50mbr propane. However if the van is running on butane you should be Ok with propane running at 30mbr pressure.

Personally I would never run butane as even in autumn or spring you can have problems with it freezing.

 

[Deleted member 207]

Propane boils (gives off enough vapour to ignite) at about -40C and Butane at about -1C, hence the difference in suitability as a fuel at low temps.

Autogas is a mixture of the two and depending on the mix can often have a boiling point of about -20C.

You can solve icing problems by having a small 12V block heater fitted prior to the regulator - very common on LPG tank installations in Germany and Scandanavia. WYNEN GAS »

 

[Deleted member 8180]

We use a bulkhead regulator and gaslow tank. In Europe the second pigtail goes to a camping gaz cylinder, in the UK we switch to a propane tank. The second cylinder is used as a spare in case we can't get autogas. We have had problems in the past with autogas (from dodgy French supermarket) failing to vapourise in UK winter, heating the van with the 'spare' propane brings it up to temp and cures it.

 

[Deleted member 967]

We had twin Alugas refillable cylinders fitted this year and I made sure that the gas that we had acquired in warmer countries was all used up and the bottles refilled with UK gas prior to the cold weather.
I did wonder about an extra pig tale that I could connect to cylinders sourced in different countries, but I discounted the Gaz version on high cost

This is a way of fitting another cylinder to a bottle or tank installation.

Extend A Stay Propane Adapter Kit on Sale

 

[lebesset]

here in france if you fill with autogas/lpg you get industrial grade propane
in the uk you get industrial grade propane
in spain you get industrial grade propane
in belgium you now get industrial grade propane [ according to my brother who lives there ...tanker fills his propane tank , then goes on and fills the autogas tank from the same load ]

I have no recent experience of other countries

industrial grade propane [ a commodity traded worldwide with agreed specification ] is largely propane , but with a mixture of other materials like napthane,butane etc in it ; in other words , it is not highly refined ; the mixture of gunk in it is generally referred to as heavy ends ...if , like me , you had run on lpg for 25 years you would know exactly what it looked like after stripping systems which had ceased to function , having become blocked with it

the only problem that comes from using this for domestic purposes is that many people 'top up ' their refillable bottles ; what happens then is that the proportion of heavy ends in the bottle increases to the point when it does not 'gas' properly [ some of the heavy ends at the bottom don't gas at all ], to the extent that , when the temperatures drop . only the propane which is at the top of the bottle will be available

this problem is easily overcome ....just don't top up the bottles except when the weather is hot , empty fully then refill ; the same problem doesn't occur when using lpg /autogas as a road fuel , then the lpg is picked up from the bottom of the tank and therefore the rubbish is used first and doesn't accumulate

 

[lebesset]

here in france if you fill with autogas/lpg you get industrial grade propane
in the uk you get industrial grade propane
in spain you get industrial grade propane
in belgium you now get industrial grade propane [ according to my brother who lives there ...tanker fills his propane tank , then goes on and fills the autogas tank from the same load ]

I have no recent experience of other countries

industrial grade propane [ a commodity traded worldwide with agreed specification ] is largely propane , but with a mixture of other materials like napthane,butane etc in it ; in other words , it is not highly refined ; the mixture of gunk in it is generally referred to as heavy ends ...if , like me , you had run on lpg for 25 years you would know exactly what it looked like after stripping systems which had ceased to function , having become blocked with it

the only problem that comes from using this for domestic purposes is that many people 'top up ' their refillable bottles ; what happens then is that the proportion of heavy ends in the bottle increases to the point when it does not 'gas' properly [ some of the heavy ends at the bottom don't gas at all ], to the extent that , when the temperatures drop . only the propane which is at the top of the bottle will be available

this problem is easily overcome ....just don't top up the bottles except when the weather is hot , empty fully then refill ; the same problem doesn't occur when using lpg /autogas as a road fuel , then the lpg is picked up from the bottom of the tank and therefore the rubbish is used first and doesn't accumulate ; in any case , the lpg is normally used faster than domestic bottles , and the heavy ends don't precipitate out to the same extent

 

[maingate]

My Burstner has a sticker in the gas compartment which says it is set up for 50 mbar.

I have one Alugas refillable with a 30 mbar regulator and one standard bottle (Energas) with a 37 mbar bottle mounted regulator.

Everything works fine from either bottle. I believe other members on here use bottles of varying pressures without any problems.

 

[Airecraft]

Cost-wise there is very little difference between bottled propane and butane. Propane is a couple of quid cheaper but less dense so you get 6kg instead of 7.5kg in the same size bottle. Propane has a higher calorific value so lasts slightly longer per kg. The main disadvantage of propane is you can carry less in the same space, a 6kg bottle lasted 19days this summer for cooking and refrigeration, last year we got 25 days from a 7.5kg butane.

 

[jann]

we permantly use propane now, but have various regulators so we dont have problems if we have to use a different bottle

 

[maingate]

Cost-wise there is very little difference between bottled propane and butane. Propane is a couple of quid cheaper but less dense so you get 6kg instead of 7.5kg in the same size bottle. Propane has a higher calorific value so lasts slightly longer per kg. The main disadvantage of propane is you can carry less in the same space, a 6kg bottle lasted 19days this summer for cooking and refrigeration, last year we got 25 days from a 7.5kg butane.

The Propane is not of a higher calorific value than Butane I am afraid.

I am not trying to be funny but this sort of thing has come up before. Because of the conflicting theories, I did a Wiki and found the following information:

Butane.....2877 Kj per mol
Propane....2220 Kj per mol

This gives Butane more energy than Propane but not by a great deal. The gasifying temperature is the biggest difference between them.

Basically, Butane will boil a kettle faster than propane, so a bottle should last longer. This is assuming the regulator is of the same pressure.

I have also seen conflicting stories about Autogas. Some people have said that the Butane content varies from European country to country and is a set amount. They even produced a chart of the variations. It is very confusing and I tend to do my own checking up now.

 

[Firefox]

Butane is C4H10 and Propane is C3H8 whereas a simpler gas like methane is CH4

So the Butane molecule has a little more bang but basically if you do winter camping forget Butane. Just switch entirely to Propane! I use those lightweight 6Kg propane bottles which are great for motorhomes.

 

[Deleted member 967]

My Burstner has a sticker in the gas compartment which says it is set up for 50 mbar.

I have one Alugas refillable with a 30 mbar regulator and one standard bottle (Energas) with a 37 mbar bottle mounted regulator.

Everything works fine from either bottle. I believe other members on here use bottles of varying pressures without any problems.

My Hymer has a 50mb regulator and a 50mb sticker yet the fridge that was fitted as standard has a sticker saying 30mb. I have had a new heater fitted that says 30mb on a sticker but this runs fine on 50mb.

If I run low on gas in Spain I will get a Repsol bottle and regulator and feed from that until I can refill my tank. I topped up the tank at Alecanti Repsol on my way here, but it is a 3 hour trip to top up again. The nearer Repsol depot in Mercia has a height restriction.

There is a new adaptor New Euro Quick Release Filler Adapter I tried to use it and it would only allow 3 litres of gas into my tank before it cut off. I know it worked OK because I lent it to another Motorhome that was trying to fill-up infront of me and he was able to fill his tank. I then moved onto the second pump and was able to put 37 litres more into the tank using the same fitting we have in the UK. I do not know if it is a problem with my tank or the new adaptor.

I used to run propane at 37mb in my caravan and found it boiled a kettle faster than a Butane at 28mb.

 

[Airecraft]

The Propane is not of a higher calorific value than Butane I am afraid.

I am not trying to be funny but this sort of thing has come up before. Because of the conflicting theories, I did a Wiki and found the following information:

Butane.....2877 Kj per mol
Propane....2220 Kj per mol

This gives Butane more energy than Propane but not by a great deal.

I agree with your data but not your conclusion. As gas is sold by mass, calorific value per unit mass is what is relevant, not per mole which is a measure of the number of atoms, ~6x10^23, and is heavier for butane.


molar mass for butane is c4H10 = (12x4) + (10x1) = 58g

molar mass for propane is c3H8 = 12x3 + 8= 44g


a kg of propane contains 1000/44 mols of gas = 2220 kj/kg x 22.72 mol = 50438 kj/ kg

a kg of butane contains 1000/58 mols of gas = 17.24 mols = 2877 kj /kg x 17.24 mol= 49603 kj / kg

 

[maingate]

I agree with your data but not your conclusion. As gas is sold by mass, calorific value per unit mass is what is relevant, not per mole which is a measure of the number of atoms, ~6x10^23, and is heavier for butane.


molar mass for butane is c4H10 = (12x4) + (10x1) = 58g

molar mass for propane is c3H8 = 12x3 + 8= 44g


a kg of propane contains 1000/44 mols of gas = 2220 kj/kg x 22.72 mol = 50438 kj/ kg

a kg of butane contains 1000/58 mols of gas = 17.24 mols = 2877 kj /kg x 17.24 mol= 49603 kj / kg

I stand corrected.

A nasty letter will be despatched first thing in the morning to Wikipedia with a demand for an apology from them regarding this matter.

 

[Deleted member 3011]

Not too far off topic.
In Morocco we had a night that was a bit below freezing but because our Butane bottle (all that is readily available in Morocco) is in the heated gas locker, we had no problems.

Next morning a Brit in a large motorhome was out wrapping his external butane bottle in a thick quilt and the hose in several layers of towelling. He explained that the heater had cut out during the night and they had frozen.
I explained that insulating the tank would only make the problem worse and suggested he use propane from his fixed tank when it was likely to be cold.

He knew better and of course, the next morning he was out pretty early wrapping it in yet more layers because it cut out even earlier this time.

Slow learner.

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As gas is sold by mass

Not autogas. That comes in litres.

Difference is not all that relevant if the temperature gets below freezing.