[Closed] refilling camping gas canister from big calor gas canister

I don't care if it is possible, just promise you'll buy a GoPro for when you try it.

i suggest a YouTube search of camping gas accidents.

I feel like an airshot could be part of the above mentioned fail. (Joking.... Please don't do this!!!)

Whilst I am sure it is technically possible I think it is one of those cases where if you have to ask then it probably isnt a good idea.

I disagree with eddiebaby though. I would go for a normal camera on a tripod in order to get a bit more range than a gopro to avoid the fireball.

There is am gadget to refill small disposables with the seal in the top from large ones - it works fine.  Calor gas might well not be the same mix - and I cannot see how you would do it.

I was thinking of taps, weighing etc etc not just a dodgy bit of pipe. As for the different mixes that should not be a issue.

I dont, but have done other gases. Yes it is "dangerous", but can be done "safely". I would use a transfer hose so you can weigh the cylinder as you fill. Temperature difference to help transfer, Nitrous systems often use heater blankets, I have seen people use buckets of hot and cold water.

Make sure you understand what you are doing in terms of liquid or gas transfer, if it has a dip tube or you are going to invert etc. Dont overfill. Whilst you can only equalize the pressure between the two cylinders you can overfill a small cylinder.

Use valves, hose, fittings etc rated for suitable working pressure.

Yup, BLEVE for the win.

I have used the 'g-works gas saver R1' to top up one camping cylinder from another, and that works fine, just never fill to more than the original new weight and check that the cylinder and threads are in good condition.

I know fittings are available to connect camping cylinders to hoses and have a friend who does fill camping cylinders from a big bottle, but I don't know the details. Camping gas is typically an 80/20 ISO-butane and propane mix, and Calor is so far as I know 100% propane. The higher vapour pressure is an advantage at low temperatures (winter camping) but potentially dangerous at summer temperatures if you use it in a stove designed for 80/20 mix. The Calor cylinders have a regulator designed to cope. If you put pure propane in a cylinder designed for 80/20 you'd need to calculate the correct weight to avoid it becoming pressured with liquid gas if the temperature increases. I know the Coleman cylinders for propane are heavier construction than their mix ones.

Greybeard .

Almost all of what you have written is wrong .

What teej said. It does work but that doesn't make it a smart move.

trailrat  there is nothing wrong with refilling the little ones using the proper gadget.

From a much bigger vessel into a small one.

Two similar sized ones I'm cool with

Using a 11kg can to fill a 100grams. You can't see how that could end badly quickly ?

we are at cross purposes trail rat.  I agree filling little ones from a calor gas bottle is wrong - the gas mix is different for a start

Calor blue "butane" bottles, red "propane" and green. They're all petroleum gasses and all are mixes in that it's just about imposible to refine a 100% pure gas, you get what comes out of the ground roughly refined on volatility. They also contain additives.

Butane

Propane

Anyone who's tried to make tea in Winter with the blue bottles knows that butane isn't very volatile. The red ones however do a lot better and if you want to make a cup of tea when it's cold then propane is what you want.

As for refilling, I wouldn't. That said, the risk will be lower with blue bottle butane for which any camping stove canister will be strong enough. Using a red propane bottle is asking for trouble unless your camping gas canister is designed for the high pressure.

Then there's the question on how well it will burn compared with the original gas mix. Best test at arm's length in a fireman's suit. edit: propane pressure is about 50% higher at room temperature.

I've had an MSR petrol stove for over 30 years which runs great at any temperature or altitude, cheap refills no more dangerous than filling your car.

Trail rat: I'm wrong about Calor being just propane - they sell propane, butane and 'patio gas' which they say is propane, I don't know why it's labelled differently.

Please tell me what else is wrong with what I wrote - I'm happy to learn. On re-reading perhaps my wording wasn't clear - I would not recommend refilling camping cylinders designed for 80/20 mix with propane (and was explaining why). If refilled with the correct amount of butane they would be safe, but whether the refilling process would be safe depends on how you do it. Although I know somebody who does this, I have not done it and am not recommending it.

I should have added butane was my plan, not propane butane mix.  Stove runs fine in mild weather on butane.

<p>Not sure why the filling operation in itself would be dangerous regardless of the sizes involved, the gas didn't get in the original bottle by itself. Having a bigger cylinder to transfer from also helps as you have a greater pressure head due to the difference on nominal volumes. Paintballers decant CO2 like this all the time, you just need the correct filling kit.</p>

you just need the correct filling kit.

What is the correct filling kit?

When you talk about paint ballers, I assume you mean air not CO2? As I understand it they use a diving cylinder as the main cylinder and fill their guns from it? Both the cylinders and the guns are tested and certified, they are also designed for multiple use.

A gas cartridge is disposal and not designed for re-use. That's why it's probably not the best idea.

<p>No I mean CO2 bulk fill, air is different and presumably a lot easier as you don't need to worry about expansion.</p><p></p><p>Although you're right about the disposable aspect, for some reason I filtered that out. Disposable cylinders should be treated as such.</p>

There are threads on howcto do this safely over on Barebones. Details on the kit and what to look out for.

Btw, comparing a liquified gas to a compressed gas is not a good idea.

I am quite pleased to have started such a controversial thread without mentioning Brexit.

Thanks splash-man.

We filled our paintball marker bottles with co2 from a massive cylinder, using a fill rig that allowed you to empty the smaller cylinders, or to fill them. Also had a pressure gauge on the input and output sides. We’d aldi weigh the smaller bottles to gauge fill level.

Used to vent a little bit of co2 onto the smaller bottle to cool it to aid transfer.

Bear in mind all pressure vessels were tested annually & the smaller bottles used on the paintball markers have burst discs fitted to avoid catastrophic damage from over pressure.

. If you put pure propane in a cylinder designed for 80/20 you’d need to calculate the correct weight to avoid it becoming pressured with liquid gas if the temperature increases.

I cannot emphasise enough quite how wrong that statement is. As it is a liquified gas the pressure in the cylinder is determined by the temperature alone. It has nothing to do with the level.

Given the low cost of gas cylinder I’m amazed that anyone would even bother to do this at home. It’s frankly just a serious accident waiting to happen.

Its slightly scary reading this, I've never refilled a non-refillable cylinder and not looked into the details much, but I do have a proper refillable 4 hole LPG tank with an emergency relief valve, float gauge and 80% fill cut off.

I'm sure some of the stuff above is correct, there is also incorrect advice, or advise that could be miss-understood.  To do it safely is highly reliant on an understanding of the risks and how to control them by weighing cylinders etc.

You can buy a 'proper' adaptor that lets you fill bog standard Calor cylinders from an LPG pump at the petrol station.  That's just plain dangerous and the reason the staff will refuse to switch the pump on if you don't have a permanent fill point on your camper/caravan.  But I'm sure there are plenty of people that think brimming a 47kg calor cylinder with liquified gas via a dodgy fill adaptor is perfectly safe...especially when that cylinder is laying in the footwell of their car!

I would put this in the 'Just because you can, doesn't mean you should" file.

Life is too short, shorter for some, could be a good Darwin Award entry.

'Man killed saving £3 on camping gas...'

Petrol stove for me, very easy to use, hot, get fuel anywhere.

"That’s just plain dangerous and the reason the staff will refuse to switch the pump on"

It's actually legislated by HSE.

Portable gas cylinders are not to be refilled on a forecourt.

That includes gasit/gaslow/easifill /safefill if the filler point is not attached to the vehicle .

And grey beard asside from gone fishins point the reason. Propane works better in winter is the liquid boils off to vapor from -42 butane stops boiling to vaporat+5. No vapor no fuel

gonefishin & trail rat, sorry, my post was badly written and was also confused because my quick Google for what Calor is was wrong.

The point I was trying to make, badly, is that all cylinders have a headspace to allow for thermal expansion of the liquid gas. The pressure in the headspace is indeed the vapour pressure of the gas. However, if the headspace is too small, thermal expansion of the liquid gas can reduce it to zero, and any further increase in temperature will result in pressurising the cylinder with <span style="text-decoration: underline;">liquid</span>. Possibly the biggest danger in refilling cylinders is overfilling, because a burst cylinder releases all the gas at once, while leaks will tend to disperse.

If you are using the residual gas in a mostly used cylinder to top up a part used one, with the same gas, you can ensure you don't compromise the headspace by checking the total weight of gas. If you are putting a different gas in the cylinder, you would need to know the right amount to ensure enough headspace, otherwise you are risk of liquid pressurisation due to overfilling. That is one of several reasons why putting propane in a cylinder designed for propane/butane mix would be a bad idea, which is what I was trying to say. But I'd misunderstood the OPs question by thinking Calor was propane, so the context wasn't obvious.

I understand the difference in boiling points, and that butane stops vapourising at cold temperature but vapour pressure does come into it as well. At temperatures where both propane and butane will vapourise, the vapour pressure of propane is higher. At 10ºC, the vapour pressure of butane is about 0.5bar gauge, while propane is about 5.5 barg, and an 80/20 mix about 1.5barg. Pure butane works at 10ºC but it's slow. At 25ºC the vapour pressure of propane would be dangerous in an appliance not designed for it - but it was only my confusion over Calor, which I've never used, that made that seem relevant to the thread.