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LPG hot water: what changes when you are not on mains gas

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An LPG system is a gas system fed from bottles or a tank. The hot water works the same way, but the fuel supply is now your problem.

An LPG hot water system is a gas hot water system that runs on liquefied petroleum gas instead of mains natural gas. The gas comes from bottles or a bulk tank on your property. It is common where no mains gas pipe runs down the street.

The heater itself comes as storage or continuous flow, just like a natural gas one. What differs is where the fuel comes from, and what happens when it runs out.

Is an LPG unit the same as a natural gas unit?

Not quite. Each appliance is built and set up for one gas type, and the data plate says which. Natural gas and LPG burn at different pressures.

Never assume a unit can swap. Converting between gases needs the right kit, and fitting it is licensed gasfitting work. Always check the data plate before you buy.

What happens when the bottle runs out?

The hot water stops, usually at a bad moment. Many homes use two bottles with a changeover device so one supplies while the other waits. Ask your gas supplier how they handle refills and deliveries to your address.

A bulk tank refilled by a supplier avoids the swap, but it is a bigger installation. Both are fuel arrangements, so they are part of the gas system and a gasfitter's job.

Does LPG suit storage or continuous flow?

Either works. Continuous flow heats only while a tap is open, so it burns no gas keeping a tank warm. A storage unit holds a tank hot all day and uses fuel to keep it there.

Which one fits depends on your household, not the gas. Our guide to gas hot water systems compares them, and storage versus continuous flow goes further.

Is LPG worth it compared with other options?

Often not, if you have another good choice. Without mains gas, a heat pump or a solar system with a booster avoids bottles altogether. LPG makes sense when electricity is a poor fit, or for a unit you already own.

We print no running costs, because gas and electricity prices vary by state, supplier and year. Get current figures from your own retailer. Compare the options in gas, electric, heat pump or solar.

What are the warning signs with bottled gas?

  • A smell of gas near the bottles or the appliance.
  • A yellow or orange flame where a blue one used to be.
  • Soot or scorch marks around the unit or its flue.
  • A burner that keeps going out.
If you smell gas, do not switch anything on or off. Get everyone outside, away from the property, and call your gas supplier or emergency services. A licensed gasfitter must check the system before it is used again.

Where can the system be sited?

Location is stricter with gas than with electricity. The appliance needs ventilation and a correctly placed flue, and bottles need a safe spot outdoors away from openings and ignition sources. Our guide to what a flue is explains why the terminal cannot go just anywhere.

If you plan a deck, fence or garden bed near an existing unit or bottles, check clearances first. Ask your gasfitter for the distances that apply to your model and state.

What should you ask before buying?

  • Which gas is the unit set up for, and is that written on the quote?
  • How many bottles does the setup use, and who delivers them to your address?
  • Where will the bottles and flue sit, and do they meet clearances for your state?
  • Is there a compliance certificate for the gas work?

This far you can go yourself

You can read the data plate, check the gas type, keep the area around the bottles and the flue clear, and order refills. You can also ask your supplier how deliveries work.

Connecting or changing bottles at the regulator, converting gas type, relighting a pilot and every other gas job is for a licensed gasfitter in every Australian state and territory. Your state or territory plumbing and gas regulator lists licensed tradespeople.

Frequently asked questions

What is an LPG hot water system?

A gas hot water system that runs on liquefied petroleum gas from bottles or a bulk tank, instead of mains natural gas. It comes as storage or continuous flow.

Can a natural gas hot water system run on LPG?

Not without conversion. Each unit is set up for one gas type, shown on its data plate. Converting needs a kit fitted by a licensed gasfitter.

What happens if my LPG bottle runs out?

The hot water stops until the bottle is replaced. Many homes use two bottles with a changeover device so supply continues.

Can I change an LPG bottle myself?

Connection work at the regulator is gas work. Ask your supplier or a licensed gasfitter what you may do at your address.

Sources

What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.