How Long Does a Gas Bottle Last with a Portable Hot Water System?

It is one of the most common questions we get asked before someone buys. "How long will the gas last?" And it’s a fair question. Nobody wants to be halfway through a shower in the middle of nowhere and run out of gas.

The honest answer is that it depends on a few things. But after more than 20 years of selling Country Comfort portable LPG hot water systems and talking with over 76,000 customers across Australia, we can give you real numbers. Not estimates off a spec sheet. Actual figures from people who have taken their unit around Australia, washed 30 people in a day, and run it continuously at shows so visitors can see what it does.

Here is what we know.

The real-world run times by bottle size

9 kg gas bottle: 25 to 38 hours

A 9 kg bottle is the most popular choice for campers and caravanners who have the space and weight allowance. In real-world use, customers consistently report 25 to 38 hours of hot water from a single bottle.

The range exists because a few things affect how hard the unit works:

- Ambient water temperature. Cold dam or tank water takes more gas to heat than water that has been sitting in a sun-warmed container.

- How long each shower runs. Short, efficient rinses use less gas than long relaxing showers.

- How often the unit fires. If you are running water constantly, it burns more consistently. If you are stopping and starting, a little extra gas is used on each ignition.

We had a group of 30 people shower in a single day from a single unit. The bottle handled it. That kind of real-world heavy use is what 25 to 38 hours actually looks like.

4.5 kg gas bottle: 14 to 15 hours

A 4.5 kg bottle is a good choice for travellers watching their packing weight, particularly when the van or camper trailer is already loaded. We use a 4.5 kg bottle at our own shows, because we are carrying stock and equipment and every kilogram counts.

At shows, we run the unit continuously for hours so customers can see the pressure, test the temperature and ask questions. Under that kind of constant use, we consistently get 14-15 hours from a 4.5-kg bottle. For a family camping trip with normal shower use, you would expect the bottle to go further.

What affects your gas run time the most

Ambient water temperature

This is the biggest variable. If you are filling your tank from a cold river in the high country in winter, the unit has to work harder to reach shower temperature than it does on a warm summer afternoon. Winter camping generally means shorter run times per bottle. If you are concerned about this, a slightly larger bottle gives you the buffer you need.

Your pump and water source

The type of pump you are running also matters. A good, consistent flow of water means the unit heats efficiently and does not hunt for pressure. A weak or inconsistent flow makes the unit work harder to maintain temperature. We cover pump recommendations in detail below, because getting the pump right is just as important as the gas bottle size.

How you use it

Quick rinses use significantly less gas than long showers. If you are at a remote campsite managing your supplies carefully, shorter showers make a genuine difference. If you have an unlimited water supply and a full 9 kg bottle, the unit will keep up with whatever you throw at it.

The pump guide: matching your setup to your needs

The gas bottle and the pump work together. Here is the breakdown we give customers based on their setup:

4.3 litres per minute: lightweight camping

This is the entry point for a bucket or small dam setup. You get in, soap up, rinse off. It works well for a couple who are conscious of their water supply and want the flexibility of running from a 20-litre bucket or a small portable tank. The shower is functional rather than luxurious, but it is genuinely hot, and it gets the job done. You can actually do a full shower in 2ltrs of water this way.

6 litres per minute: the full shower experience

This is the pump we recommend for most campers and caravanners. With a consistent 6 L/min supply, Country Comfort delivers a proper hot shower with real pressure. If you have an endless water supply, this is a dream setup. It is the starting point for a good camping hot water system.

12.5 litres per minute: tanks and off-grid setups

If you are running from a tank, a rainwater collection system, or any setup where the water has to travel further through hoses or a filter, you need at least 12.5 L/min to maintain consistent pressure. The unit has a built-in filter, and you need enough flow to push through it reliably. Gravity-fed systems generally do not produce enough pressure for consistent hot water, so a pump is advised in those setups.

Planning your gas for a trip

- A simple way to think about it before you head off:

- 9 kg bottle: suited to a couple or family for a week or more of regular showers, or a group on a shorter trip with heavy use.

- 4.5 kg bottle: suited to a couple for a long weekend, or solo travellers wanting to keep weight down.

- Two bottles on rotation: if you are going remote for an extended period and cannot resupply, take two. The peace of mind is worth the weight.

Country Comfort is AS2658-certified (certificate GMK10277), meaning it is built and tested to Australian standards for safe LPG operation. That certification also means the unit runs efficiently. You are not losing gas to a poorly calibrated system.

Frequently asked questions

How long does a 9 kg gas bottle last with a Country Comfort portable hot water system?

In real-world camping and caravanning use, a 9 kg bottle typically lasts between 25 and 38 hours depending on ambient water temperature, shower duration, and how frequently the unit fires. A group of 30 people showered in a single day from one unit. Colder water temperatures and longer showers reduce run time.

How long does a 4.5 kg gas bottle last with Country Comfort?

Approximately 14 to 15 hours of continuous use. This figure is based on running the unit constantly at trade shows, so normal intermittent camping use would typically stretch the bottle further.

Does cold weather affect how long the gas lasts?

Yes. In cold conditions, the unit has to work harder to heat cold water to shower temperature, which uses more gas. If you are camping in alpine or winter conditions, budget for a shorter run time or take a larger bottle.

What pump do I need to run Country Comfort?

For a lightweight bucket or tank setup, a 4.3 L/min pump works for a functional rinse. For a full shower with good pressure, a 6 L/min pump is recommended. For tank-fed or off-grid setups with hoses or a filter, you need at least 12.5 L/min to maintain consistent flow. Gravity-fed systems do not produce reliable enough pressure for safe, consistent operation.

Can I use Country Comfort with a gravity-fed water supply?

Gravity feed alone generally may not produce sufficient or consistent pressure for the unit to operate reliably. A pump is recommended for any setup where water is not supplied at mains pressure.

Ready to set up hot water at your campsite?

Country Comfort is Australia's original certified portable LPG hot water system. AS2658 certified, built to Australian standards, and backed by over 76,000 Australians who have taken it camping, caravanning, and off-grid.

Visit the Country Comfort portable hot water system page for full specifications and to order. If you have questions about which setup is best for your trip, call us directly. You will speak to Rhonda or Steve, the same two people who have been behind Country Comfort since 2006.