Came across this on the " Caravan Guard " E magazine, every day I learn summat new !! another useful site

"One of the simpler and more scientific ways of accurately checking how much gas is in a metal cylinder is to pour hot water down the side. Safely disconnect and remove the gas cylinder from your leisure vehicle and pour hot water down the side of the gas cylinder. After a moment you should start to see a line of condensation form on the gas cylinder, which indicates the level of gas."

I did that with the gas bottle in situ. If you are going to disconnect it is more accurate to weigh it. The weight of the empty bottle is stamped on the collar on the bottle. ( In pounds and ounces on Calor 😄) . In the end, if you don't want gas anxiety, you need 2 bottles.
Steve

2 bottles, one gas and one wine?

Motorhome-owning friends of ours have all the gadgets under the sun - They have just bought a new camper with a built-in LPG tank and so they have passed on to me a Truma LevelControl that attaches magnetically to the underside of an LPG bottle and senses how much gas you have ultrasonically and sends the info (as a % and in litres) to an app on your phone/computer. Will save having to weigh the cylinder I hope…

If your cylinder is aluminium you stick a steel plate to the underside.

More details to follow when I try it out. Hopefully not long now until the first camping trip…

Ah yes. I have a Gaslow gauge on my bottle, but it only tells you (approximately) how much is in it whilst you are using it. Presumably by pressure. Just turning on the bottle won’t give you an accurate reading. What this Truma gauge will do, so it claims, is give you an accurate reading at any time. Even whilst towing, or in storage. I wouldn’t buy one without trying one first, but I’m not looking a (free) gift horse in the mouth either

At least, when the hissing stops, you'll know for sure that it's empty...

So to check the gas I need a gadget and then have to buy an i-phone to get an app !!!! think I will stick to shaking the bottle

I'm lazy and I only want to remove the bottle when all else fails - or it's finally empty! I already have an iPhone and the gadget is being given to me for free, so i will definitely try it out

Could you check mine as well then?