Apologies, I did read the 3 month rule but was on auto pilot there! Used to a local car forum where we do that. Will keep that in mind.
Thanks for the advice, will maybe just play it safe and get a buntane and look again next season when we’re not so close to heading off
Butane is fine as long as the ambient temperature remains above about 5C. The reason is because the liquefied gas inside the cylinder draws heat from the atmosphere around the cylinder to have the energy to evaporate the liquid into its gaseous state, and the vapour pressure it creates in the cylinder is also temperature dependant. the lower the ambient temp the lower the cylinder pressure.
In addition as you use gas from an LPG cylinder (Butane and Propane) the cylinder needs to evaporate more liquid to replace the gas you have used. This further cools the liquid content of the cylinder, so even though Butane theoretically would stop gassing off at 0C the fact gas usage cools the liquid below ambient means that for practical purposes Butane can become temperamental at about 5C ambient.
Exactly the same thing happens to Propane but the big difference is it has to be cooled to about -40C before it stops gassing off. So Propane is the choice for winter caravanning, and in fact its safe for all year round use in the Europe and the UK.
The cost of buying a Propane pigtail is typically between £10 to £15, If you are competent you can change it your self, but its literally a 5min job .
Generally Propane is cheaper to buy compared to Butane, and whilst there is a slight difference in the heat that can be obtained from the same mass of either LPG, its small and you are not likely to notice it. Propane cylinder can often be found cheaper from builders merchants, than caravan/leisure retailers.