When it comes to heating water in your home or business in Australia a gas hot water system remains one of the most efficient and cost effective solutions. Whether you choose a gas storage water heater or a gas instantaneous water heater each type has unique advantages tailored to different household needs. In this article we explore how gas hot water systems operate compare efficiency and performance and outline key installation considerations to help you make the right choice for your property.
What is a Gas Hot Water System?
A gas hot water system heats water using natural gas or LPG (liquefied petroleum gas) as the energy source. Gas water heaters are popular across Australia because of their ability to deliver reliable hot water at lower running costs when compared with electric systems. They come in two main forms – storage models that hold a volume of pre heated water and instantaneous or tankless models that heat water on demand.
Understanding the differences between these options can help you choose the system that best suits your lifestyle budget and hot water demands.
Gas Storage Water Heater Basics
A gas storage water heater stores and heats a large volume of water ready for use. These systems consist of an insulated tank combustion chamber burner controls and safety features.
How Gas Storage Water Heaters Work
- Cold water enters the tank from the mains supply and rests in the insulated vessel.
- The gas burner heats the water to a preset temperature typically between 60 and 65 degrees Celsius.
- Heated water is stored until it is needed. When you turn on a tap hot water flows out and is replaced by cold water at the bottom of the tank ready to be heated.
Benefits of Gas Storage Water Heaters
- Reliable supply of hot water for multiple uses at once such as showers washing and dishwashing.
- Lower installation costs relative to some instantaneous systems.
- Proven technology that many households understand and trust.
- Good for households with high peak demand at certain times of the day.
Limitations to Consider
While gas storage water heaters deliver hot water reliably they do have some drawbacks:
- Standby heat loss because water is kept hot 24 hours a day. Even in an insulated tank some energy is lost which may raise running costs.
- Size of tank limits supply so in larger households or high usage scenarios you may run out of hot water.
- Footprint and space because the tank requires a designated space indoors or outside with adequate clearance.
Gas Instantaneous Water Heater Essentials
Also known as a tankless or on demand water heater a gas instantaneous water heater heats water only when you need it. This means there is no storage tank and no continuous heating.
How Gas Instantaneous Water Heaters Work
When a hot tap is turned on cold water flows through the unit past gas burners or heat exchangers. The water is heated instantly to the set temperature and delivered to your tap shower or appliance. When the tap is switched off heating stops.
Key Advantages
- Energy efficiency because water is heated only when needed. This eliminates standby heat loss and can significantly reduce running cost.
- Endless supply of hot water so you never run out on long showers or during heavy usage.
- Compact size and flexibility making it easier to install in tight spaces.
- Longer service life with fewer components at risk of corrosion compared with storage tanks.
Potential Challenges
While gas instantaneous water heaters offer great benefits they also have some factors to weigh up:
- Higher upfront cost as the technology and installation can be more expensive than simple gas storage water heaters.
- Flow rate limits so if too many outlets are used at once performance may drop.
- Gas supply size matters and properties with limited gas capacity may need upgrades to support a high flow tankless system.
Gas Storage vs Gas Instantaneous
Choosing between a gas storage water heater and a gas instantaneous water heater comes down to how you prioritise cost water use and space.
| Feature | Gas Storage Water Heater | Gas Instantaneous Water Heater |
| Hot water availability | Stored supply | On demand unlimited |
| Energy efficiency | Lower due to standby loss | Higher no standby loss |
| Installation cost | Lower typical | Higher typical |
| Space required | Larger tank space | Compact |
| Best for | High peak usage at set times | Steady usage throughout day |
For families with busy mornings and evenings or where multiple showers may run at once a storage unit can handle bursts of demand. In homes with more spread out usage or where energy efficiency and space saving are priorities instantaneous units can deliver benefits.
Efficiency and Running Cost
Gas hot water systems are generally more cost effective to run than electric options especially in areas where gas is competitively priced. However efficiency varies based on system type insulation and how the system is used.
Gas Storage Efficiency
Gas storage water heaters lose heat over time as the stored water cools. Better insulation can reduce this loss but some standby energy expense is unavoidable. Choosing a well sized tank and setting the thermostat appropriately can optimise performance.
Gas Instantaneous Efficiency
Gas instantaneous water heaters are more efficient because they heat only the water required at that moment. Without a tank waste is minimal which improves overall energy use. Efficiency ratings such as energy star or WELS water rating should be checked when selecting a model to ensure strong performance.
Operating Costs
Running cost depends on gas price and hot water demand patterns. Even with higher upfront costs instantaneous systems can deliver lower operating expenses over time with careful management.
Installation Considerations
Installing a gas hot water system requires careful planning and must comply with Australian standards and local regulations. Whether you choose storage or instantaneous the following factors are key:
Location
Your installer will help you determine the best location for the hot water system. For gas storage systems this includes space for tank clearance ventilation and accessible maintenance. For instantaneous units proper venting and clearance from combustible materials is essential.
Gas Supply and Pressure
Ensuring adequate gas supply and correct gas pressure is critical for optimal performance. Tankless models in particular require consistent gas flow to deliver high temperature water on demand. In some cases a gas line upgrade or regulator adjustment may be necessary.
Water Pressure
Gas hot water systems must operate within certain water pressure ranges. If your home pressure is too low a booster pump may be recommended. Conversely pressure limiting valves may be required if water pressure is too high.
Ventilation and Safety
Proper ventilation ensures combustion gases are safely expelled. This is vital to prevent carbon monoxide buildup. Vented flues or direct exhaust systems may be needed depending on model and installation location.
Compliance and Certification
Licensed plumbers and gasfitters must install gas hot water systems in Australia. They will ensure compliance with plumbing codes and safety standards giving you peace of mind that the system is safe and legal.
Sizing Your Gas Hot Water System
Selecting the right size is key to performance satisfaction and efficiency:
- Gas storage water heater sizing depends on household members typical usage patterns and peak demand. Tanks are measured in litres and common sizes range from 125 to 315 litres. Too small a tank means cold water runs out quickly; too large raises cost and space requirements.
- Gas instantaneous water heater sizing is based on flow rates measured in litres per minute and desired temperature rise. A system must be capable of delivering enough hot water to meet simultaneous hot taps.
Consulting with a professional plumber ensures the system selected matches your real needs rather than guesswork.
Maintenance and Service
Regular servicing prolongs system life improves safety and keeps efficiency high. Typical maintenance includes:
- Flushing storage tanks to remove sediment
- Checking gas burners and venting
- Inspecting heat exchanger and burners on instantaneous units
- Testing pressure relief valves and controls
A yearly service by a licensed technician can prevent costly breakdowns and ensure your system runs efficiently.
Which is Best for You?
There is no one size fits all answer to the question of whether a gas storage water heater or a gas instantaneous water heater is better. Here are some quick scenarios to help guide your decision:
- Large family with high peak demand – gas storage water heater might be more reliable for simultaneous use.
- Energy conscious household with limited space – gas instantaneous water heater offers high efficiency and compact installation.
- Budget conscious installation with long term cost savings goal – weigh installation cost versus operating cost over time.
At Efficient Pure Plumbing our experts can assess your property usage and recommend the right system based on performance reliability and cost.
Conclusion
Gas hot water systems remain a trusted choice for Australian homes and businesses. With options like gas storage water heaters and gas instantaneous water heaters you can find the right balance of efficiency cost and convenience. By understanding how each system operates and what makes them unique you can make an informed decision.
From installation to maintenance we are here to support you in choosing a gas hot water system that meets your needs now and into the future.
