Open Air Camp Kitchen: Guide To Canister Gas Stoves
Over the next few weeks, we’ll be bringing you a series of articles looking at cooking in the great outdoors. Hopefully, they will provide some useful advice and inspire you to start planning and preparing for your next trip, once it is safe to go camping again. In the meantime, please do stay home and stay safe!
We begin our series with an in depth look at canister gas stoves. If you’re starting out backpacking and looking for a stove suitable for UK camping, a gas stove is our choice for its simplicity, speed, ability to control the flames and the availability of canister gas.
- Stove types
- Canister types
- Lighting your stove
- (Not) Using your stove in a tent
- Estimating gas consumption
- Increasing efficiency
- Using a stove at low temperatures
- Disposing of used canisters
Types Of Canister Gas Stoves
There are 3 main styles of canister gas stoves available in the UK.
These are really easy to use and highly efficient, so they are perfect for boiling water quickly. They are integrated systems involving a stove that fits on top of the gas canister, a dedicated pot – normally with heat exchanger fins for extra fuel efficiency – and a windshield. However, to achieve the fast boil times, the burner heads tend to be very powerful which can create hotspots on the bottom of the pan. You are normally limited to just the dedicated pot, which is often tall and narrow, so cooking is more limited.
These are compact and light to carry. Unlike the integrated systems, you can use different pots, including wider ones as long as they will sit on the pan support arms. However, they can be slightly less efficient as the burner head and flames are not so enclosed, and, as pans sit quite high off the ground, they are not the most stable on rough ground or with heavy or wide pots.
Remote canister stoves, like the Primus Express Spider.
These are great for winter trips, for more adventurous recipes, or cooking for larger groups as they are more stable and easier to use with bigger pans. They perform better than canister top stoves in bad weather as you can enclose the pot fully with a windshield, and most have a pre-heat tube for extra assistance in winter. The downside is they’re slightly larger and heavier than canister-top versions, but at 200g, the Primus Spider is still no heavyweight.
Types Of Gas Canisters
There are a number of different canister types available. The vast majority of gas stoves available in the UK take a threaded screw-in canister, including those sold at Open Air. You’ll also find this style of canister the most widely available when travelling abroad. In some parts of the world – especially continental Europe – you’ll also encounter canisters featuring a twist-style fitting (also known as Easy-Clic) and pierceable canisters which are often the only options available, so it’s important to have either an appropriate stove or adaptor when travelling through those regions.
Lighting Your Stove
You’ll need a way of lighting the stove – traditional options are matches, a lighter, or a fire steel to produce sparks. Some newer stoves include a handy integrated piezo igniter, but on long or remote trips it’s a good idea to take a back up option just in case this breaks.
(Not) Using Your Stove In A Tent
Stoves shouldn’t be used inside tents. As well as the risk of burning your tent down, stoves produce both carbon dioxide and carbon monoxide (depending on how efficiently they burn), so you should use them in a well-ventilated area. If it’s truly awful weather, and you have no other option, you might need to very carefully use the tent porch and vent the cooking area as much as possible.
Estimating Gas Consumption
Estimating how much fuel you’ll need can be tricky. It depends how much you use the stove, the conditions, and the efficiency of your stove and pot/lid/windshield set up. As an example, the Primus Spider will run for up to 2 hours on one standard 230g gas canister, and take about 4 minutes on average in good conditions to boil water. That’s about 30 litres of boiled water. For drinks, that’s easy to calculate how much you’ll need, but it’s harder for food.
When backpacking, I normally have a large hot drink at the start and end of the day, porridge for breakfast and a hot meal for dinner. All of these involve bringing water to the boil, but since I use a pot cosy (see our tips below!), I don’t need to use much fuel simmering or keeping food warm. I’d estimate this is roughly equivalent to boiling 3L of water per day, and so a full canister would last me about 10 days at this level of use on a solo non-winter trip. As Americans would say, your mileage may vary! These results all depend on the stove and the conditions – if you are cooking for groups, melting snow, having to boil water to sterilise it, or don’t use a windshield, you’re going to need a lot more fuel! When you get home after your next trip, I recommend working out how much fuel you used per day and use that as a guide.
The easiest way to make your gas last longer is to stop heat escaping from your pot unnecessarily. Just like at home, a pot lid stops heat escaping out of the top of the pan, whilst using a windshield around the pot blocks the wind and makes a surprisingly big difference when cooking outdoors. However, be careful if using a windshield with a canister top gas stove; it is important not to fully enclose the flame in a way that might lead to the canister becoming hot as this is very dangerous! This clever design from Primus for canister top stoves leaves a gap on one side to avoid this problem.
Insulated pot cosies are another good way to save fuel. For meals that would normally require simmering, heat them up, then pop your pot in a pot cosy to trap heat and keep your meal warm without needing to keep the stove running. It also frees up your stove for another job in the meantime, like making a brew!
Using A Gas Stove At Low Temperatures
Although we refer to “gas”, the fuel inside the canister is pressurised, and can be in liquid form. To burn well, it first needs to vaporise into a gas. In normal conditions, this happens when you open the valve as the fuel can expand and draw enough heat from the surroundings. However, in colder temperatures, the surroundings don’t offer enough heat, meaning gas can struggle to vaporise and remain as a liquid inside the canister, and ultimately . There are a few things you can do to help:
- Choose a remote canister stove with a pre-heat tube. This is a brass loop that takes the fuel through the flame first to warm it up before it reaches the burner, helping the gas to vaporise.
- Warm the gas cylinder with your hands and insulate it from the ground – the extra warmth and reduction in heat loss can help the gas to vaporise and make a difference to the power of the stove.
- Below about 5oC, use a cylinder with a winter gas mix – this will contain a higher proportion of propane, which has a lower boiling point (-42oC) than butane (-1oC) and so will stay as a gas down to lower temperatures. Primus Winter Gas cylinders are especially clever as they use a vapour mesh on the inside to help gas vaporise and burn more efficiently, even if the canister is nearly empty, all the way down to -22oC! Save these for cold weather, however, as in hot temperatures the extra power can be too much for a stove and cause it burn inefficiently and use too much fuel.
- Some (but not all) remote-canister stoves are designed so that they can run with the cylinder upside down, like the MSR WhisperLite Universal. This helps in two ways: firstly, by preserving the mix of propane and butane; and secondly, by drawing off liquid fuel and allowing it to vaporise in the pre-heat tube, which might otherwise struggle to vaporise within the canister.
If the canister is used in its normal, upright, position, the vapour at the top of the canister will be burnt off first, leaving liquid at the bottom of the canister, which then struggles to vaporise. Also, the propane is more easily vaporised, so will be burned off first, leaving almost entirely the poorer performing butane behind. If the canister is inverted, liquid fuel is drawn down the hose and into the pre-heat tube, where it can vaporise more easily in the heat of the flames (NB you’ll want to light the stove with the canister in the normal position, and then invert once it’s been lit). This means butane and propane are used at roughly the same rate, rather than burning propane in preference, and the remaining fuel mix is preserved. As the fuel hose is now at the bottom of the canister, you’re not left with fuel that needs to vaporise to escape but can’t get enough heat to do so.
Needless to say, if you stove is not designed to handle this mode of operation, it can be very dangerous and you shouldn’t attempt it!
Dealing With Half-Empty And Used Canisters
At the end of a trip, you can often be left with a half-full gas canister. To work out how much fuel is left, you can simply weigh it and deduct the weight of an empty canister – about 95g for a 100g canister and 125g for a 230g canister. A simple method out on the trail is to carefully put the canister in water and see how deeply it sits in the water – this will indicate the level of gas remaining!
Unfortunately, empty canisters can’t be refilled and recycling them can be tricky. If you own a canister gas stove, we’d highly recommend purchasing the JetBoil Crunch-It, a small tool that allows you to depressurise the canister and safely puncture it so you can dispose of it with your normal household recycling – but check your local rules!
There you have it! I hope you’ve found our tips on using a canister gas stove helpful! As always, if you have any further questions, you can visit us at our Green Street, Cambridge store, or contact us via email or Live Chat.