The Best Gas Bottles, Regulators & Fittings

Gas runs the two things you use most on a big lap: your cooktop and your hot water. Get the bottle size, regulator type and fittings right, and you’ll refill every few weeks without a second thought. Get it wrong, and you’ll run out of gas mid-shower in a free camp three hours from the nearest servo, or worse, fail a gas compliance check.

This guide covers what bottle sizes actually make sense on the road, which regulators are worth buying, and the fittings you need to keep everything legal and leak-free.

What Gas Bottle Size Do You Need?

Australian LPG bottles for caravans come in a few standard sizes. The three you’ll actually deal with are 4kg, 4.5kg and 9kg. The 8.5kg and 9kg bottles are the same physical size in practice, and 9kg is the one you’ll see on almost every caravan A-frame.

The best setup for a big lap is two 9kg bottles. That’s roughly 18kg of gas, which for a couple cooking daily and running gas hot water lasts around eight to twelve weeks. When one empties, an automatic changeover regulator switches to the second, giving you time to refill without ever running dry.

If you also run a three-way fridge on gas or use gas heating in the cold country, plan on refilling more often. A three-way fridge alone can chew through a 9kg bottle in about three weeks.

Steel vs Composite Bottles

Standard steel bottles are what most caravans come with, and for good reason. They’re cheap, tough, and every swap service and servo will refill or exchange them without question.

Composite bottles (the translucent ones from brands like Viking) are lighter by around 40% and let you see the gas level. That’s a real advantage on the A-frame where every kilo of ball weight counts. The downsides: they cost two to three times more upfront, and not every regional servo will refill them because some staff aren’t confident handling them. Swap-and-go services generally only handle steel bottles.

Which should you buy?

For most big lappers, stick with steel 9kg bottles. They’re bulletproof, universally accepted, and cheap to replace if one gets damaged. Composite is worth the premium only if you’re weight-obsessed (light camper trailers, weight-limited A-frames) and you’re happy to plan refills around bigger towns.

Regulators: Which Type to Buy

The regulator drops the high pressure in the bottle down to the low pressure your appliances need (2.75 kPa in Australia). There are two types worth knowing.

Single-stage / single-bottle regulators

These connect one bottle to your system. They’re cheap and simple, but when the bottle runs out, everything stops until you swap it over. Fine for a camper trailer with one bottle, frustrating on a caravan.

Automatic changeover regulators

These connect two bottles at once. When the first empties, the regulator automatically switches to the second and a small indicator changes from green to red. You keep cooking and showering without interruption, then refill the empty bottle whenever it’s convenient. For anyone doing a big lap, this is the setup to have.

Our Top Bottle & Regulator Picks

Fittings, Hoses & Adaptors

Australia uses two main bottle connection types. Knowing which one you have saves a lot of grief.

POL vs ACME (Type 21)

POL fittings are the older left-hand-thread connection, tightened with a spanner. Reliable but fiddly. ACME (Type 21) is the newer hand-tightened connection with a built-in safety feature that shuts off gas flow if there’s no appliance connected. Most new bottles and regulators use ACME. If your regulator and bottle don’t match, you’ll need an adaptor.

Pigtail hoses

The short flexible hoses connecting each bottle to the regulator are called pigtails. They perish over time and are a common leak point. Replace them every few years, and always carry a spare. A cracked pigtail in a remote spot means no gas until you find a replacement.

Refilling and Swapping on the Road

You’ve got two ways to top up gas on a big lap.

Refilling is where a servo or gas depot pumps LPG into your own bottle. It’s cheaper (you only pay for the gas) and you keep your own bottle, but it’s only available where they have a refill pump and staff qualified to operate it. Many outback servos still do this.

Swap-and-go exchanges your empty bottle for a full one at supermarkets, hardware stores and servos. It’s convenient and available almost everywhere, but you pay a premium and you might hand over a near-full bottle for a slightly older one. Only works with standard steel bottles.

The smart approach: refill when you can (cheaper and you keep your good bottles), and use swap-and-go as backup when refilling isn’t available. With an auto changeover regulator you’re never in a rush, so you can wait for a cheaper refill rather than paying swap prices out of desperation.

Safety, Compliance & Gas Checks

Gas is the one system on your rig where cutting corners can end very badly. A few rules keep you safe and legal.

• Gas certificate: Many caravan parks and all registration renewals in some states require a current gas compliance certificate. A licensed gas fitter checks your system every few years.
• Only licensed fitters modify gas systems: You can swap bottles and replace pigtails yourself, but any changes to fixed gas lines or appliances must be done by a licensed gas fitter.
• Turn bottles off when towing: Shut the bottle valves before driving. A three-way fridge should never run on gas while you’re moving with a full tank of fuel.
• Check for leaks regularly: Soapy water on every connection after each bottle change takes 30 seconds and could save your life.

For how gas ties into the rest of your caravan setup, our appliances and hot water guides go deeper on the systems your gas actually runs.