Best Continuous Flow Gas Hot Water Systems in 2025: JR Gas & Water Awards

Choosing the best continuous flow gas hot water system in 2025 is not just about picking the biggest litres-per-minute rating or the most expensive model.

The right system depends on your household size, number of bathrooms, gas supply, installation location, budget, flow rate needs, warranty support and whether you are replacing an older continuous flow unit, changing from gas storage, or upgrading from electric hot water.

For Brisbane, Gold Coast and South East Queensland homes, continuous flow gas hot water remains a popular choice because it heats water on demand, uses a compact wall-mounted unit, and avoids the bulk of a storage tank. JR Gas & Water’s instant gas range includes systems from 10L to 32L per minute, with options from brands including Rinnai, Rheem, Bosch and Thermann, plus size-based categories for 1, 2, 3 and 4 bathroom homes. (JR Gas and Water)

This 2025 awards guide ranks the best continuous flow gas hot water systems by real-world suitability, not just spec sheet numbers. It uses the supplied JR draft as the base and refines it into a stronger buyer-focused guide.

Quick answer

The best continuous flow gas hot water system for most family homes in 2025 is the Rinnai B26 Instant Gas Hot Water System. It offers a strong balance of installed value, 26L/min capacity, brand confidence and practical performance for many standard homes. JR Gas & Water lists the Rinnai B26 as a 26L system with a 12-year maximum warranty and natural gas supply by default, with LPG available where requested. (JR Gas and Water)

For homeowners wanting a premium Rinnai option, the Rinnai Infinity 26 is a strong step up. For value-focused buyers, the Rheem 26 and Vulcan DUOMAX 26 are worth comparing.

If you are replacing an old gas unit, JR Gas & Water can help compare instant gas hot water systems, gas storage hot water systems, heat pump hot water systems, and hot water repairs and servicing.

What is a continuous flow gas hot water system?

A continuous flow gas hot water system heats water as it passes through the unit. Instead of storing hot water in a cylinder, the system detects water flow when a hot tap opens, lights the burner, and heats the water on demand.

This is why continuous flow systems are also called instant gas hot water systems.

Continuous flow gas hot water can suit:

• homes with natural gas or LPG

• households wanting hot water on demand

• homes replacing an older instant gas system

• properties where a wall-mounted unit is preferred

• homes with limited space for a storage tank

• families wanting continuous hot water when the system is correctly sized

• granny flats, townhouses and family homes

• properties moving away from older gas storage hot water

It may not suit:

• homes without suitable gas supply

• properties with undersized gas pipework

• homes better suited to heat pump hot water

• households wanting to reduce gas use

• sites where the unit would be installed too far from key fixtures

• homes with complex internal flueing requirements

• installations where electrical, gas or plumbing upgrades make another system type better value

Continuous flow does not mean unlimited flow for every situation. It means the system can keep heating water continuously while demand stays within the unit’s capacity.

How we judged the 2025 awards

We ranked these systems based on the factors that matter after the unit is actually installed.

Our judging criteria

• Flow rate in L/min

• Energy efficiency

• Installed value

• Brand reputation

• Warranty support

• Parts and servicing support

• Natural gas and LPG availability

• Installation practicality

• Household suitability

• Upgrade flexibility

• Smart control or controller options

• Long-term ownership value

We gave extra weight to three practical categories.

1. Correct sizing

A 26L unit can be excellent in the right home, but oversized or undersized in another. Flow rate should match bathrooms, occupants, simultaneous use and gas supply.

2. Installed value

The cheapest unit is not always the best installed outcome. Gas pipe sizing, valves, power, tempering, relocation and compliance requirements can affect the real cost.

3. Support and reliability

Hot water systems are long-term installed products. Brand support, parts availability, warranty terms and installer experience matter.

2025 continuous flow gas hot water system award winners

Best Overall Continuous Flow Gas Hot Water System: Rinnai B26

The Rinnai B26 Instant Gas Hot Water System takes our 2025 Best Overall award because it gives many homes the best balance of performance, price and brand confidence.

Best for

• standard family homes

• 2 to 3 bathroom homes where demand suits

• replacing older continuous flow systems

• homeowners wanting a proven Rinnai option

• customers wanting strong value without premium extras

• natural gas or LPG properties where the correct setup is selected

Why it won

The Rinnai B26 is the all-rounder. It gives many households a practical 26L/min continuous flow system without stepping into unnecessary premium features.

JR Gas & Water lists the Rinnai B26 with a 26L volume rating, compact dimensions, Japanese manufacture, and natural gas supply by default, with LPG requested where available. (JR Gas and Water)

For many homes, that makes it the sensible first comparison point. It is not trying to be the flashiest system on the market. Its strength is that it does the core job well: reliable on-demand gas hot water in a compact wall-mounted format.

Things to consider

The B26 does not include every advanced feature found in premium models. If you want higher-end controls or a more premium Rinnai system, compare it with the Rinnai Infinity 26.

Best Premium Continuous Flow Gas Hot Water System: Rinnai Infinity 26

The Rinnai Infinity 26 is a strong premium choice for homeowners who want a recognised continuous flow name with higher-end positioning.

Best for

• homeowners wanting a premium Rinnai system

• family homes with suitable gas supply

• customers comparing long-term ownership value

• replacements where the existing setup suits a 26L system

• homes wanting stronger brand confidence

• buyers who prefer a higher-end model over a basic unit

Why it ranks highly

The Rinnai Infinity range is one of the best-known names in continuous flow gas hot water. For customers who want a premium system rather than the cheapest installed option, the Infinity 26 is a serious contender.

It suits homeowners who want a reliable 26L-class unit and are comfortable paying more than entry-level pricing for a higher-profile system.

Things to consider

Premium does not remove the need for correct sizing. If the home’s gas supply, water pressure or installation location is not suitable, even a premium unit can disappoint.

Best Continuous Flow System for Smart Control: Rinnai Infinity Touch 26

The Rinnai Infinity Touch 26 is the best fit for homeowners who want more control over temperature and user experience.

Best for

• tech-focused homeowners

• families wanting easier temperature control

• homes where controllers are a priority

• customers wanting premium convenience features

• households wanting more control than a basic unit offers

Why it ranks highly

Smart controls can be useful when the household wants better temperature management, especially where different users have different preferences.

This type of system is not necessary for every home, but it can be attractive for customers who value convenience, interface quality and more control over day-to-day hot water use.

Things to consider

Smart control features add cost. Some households will be better off spending that money on correct sizing, installation upgrades or a better match for their gas supply.

Best Reliable Standard Performer: Rheem 26

The Rheem 26 Instant Gas Hot Water System is a strong option for homeowners who want a recognised hot water brand with practical continuous flow performance.

Best for

• standard family homes

• customers comparing Rinnai and Rheem

• homeowners wanting major-brand confidence

• like-for-like continuous flow replacements

• households wanting a 26L-class gas system

• Brisbane and Gold Coast homes with suitable gas supply

Why it ranks highly

Rheem is one of the most recognised hot water brands in Australia. For homeowners who prefer Rheem over Rinnai, or already have Rheem hot water equipment, the Rheem 26 is a practical option to compare.

It sits in the mainstream 26L continuous flow category and can make sense for households wanting dependable gas hot water without overcomplicating the decision.

Things to consider

As with other 26L systems, site suitability matters. Gas pipe sizing, water pressure, installation location and whether multiple bathrooms will run at the same time should all be checked before choosing.

Best Budget Continuous Flow Gas Hot Water System: Vulcan DUOMAX 26

The Vulcan DUOMAX 26 wins Best Budget Option because it gives homeowners a lower-cost pathway into a 26L-class continuous flow gas system.

Best for

• budget-conscious homeowners

• rental properties

• straightforward replacements

• owners wanting practical value

• households that do not need premium features

• customers comparing installed price first

Why it ranks highly

The Vulcan DUOMAX 26 is a practical choice when the priority is getting reliable continuous flow gas hot water without paying premium-brand pricing.

For rental properties, first-home buyers or customers replacing a failed older system, it can be a sensible value option if the household demand and installation conditions suit.

Things to consider

Budget systems should still be selected carefully. If the home has high demand, complex gas supply requirements or a difficult installation location, the cheapest unit may not be the cheapest final result.

Best Smaller Home Option: Bosch Hydropower 16H

The Bosch Hydropower 16H is a compact option for homes with lighter hot water demand.

Best for

• smaller homes

• units and townhouses

• one-bathroom properties

• households with lower simultaneous demand

• customers who do not need a 26L system

• some rental or secondary dwelling setups

Why it ranks highly

Not every home needs 26L/min. For smaller homes, a lower-flow unit can be more suitable, especially where only one bathroom is in regular use.

A compact 16L continuous flow system can make sense where demand is lighter and the customer wants a smaller, simpler gas hot water option.

Things to consider

A 16L unit is not ideal for larger families or homes with multiple showers running together. If the home has two or more bathrooms, compare larger systems first.

Best Eco-Focused Continuous Flow Gas System: Rinnai Enviro 26

The Rinnai Enviro 26 is the strongest option for homeowners wanting a higher-efficiency gas continuous flow system.

Best for

• eco-conscious homeowners

• customers wanting higher gas efficiency

• homes where long-term gas use matters

• buyers considering condensing technology

• households wanting a premium efficiency option

Why it ranks highly

Condensing continuous flow systems are designed to recover more heat from the combustion process, improving efficiency compared with standard units.

For homeowners who want to stay with gas but care about long-term energy use, a higher-efficiency system can be worth comparing.

Things to consider

Condensing systems can cost more upfront and may have extra installation considerations, including condensate drainage. They are best suited to customers who are comparing lifetime value, not just initial price.

Best Standard Efficiency Alternative: Thermann 26L

Thermann 26L systems can be a practical alternative for homeowners comparing value-focused continuous flow gas options.

Best for

• standard family homes

• customers comparing non-premium brands

• value-conscious replacements

• households wanting a 26L-class system

• properties where the installed package matters more than brand prestige

Why it ranks highly

Thermann systems can sit in the useful mid-market space for customers who want continuous flow gas hot water without necessarily choosing Rinnai or Rheem.

They can be worth comparing where the product, warranty, price and installation package suit the job.

Things to consider

Brand support, warranty terms and parts availability should be compared carefully before choosing any mid-range or budget system.

Best Budget Backup Option: Dux Always Hot 26

The Dux Always Hot 26 is a budget-friendly 26L option for customers wanting a simple continuous flow system.

Best for

• budget-conscious homes

• rental properties

• straightforward replacement jobs

• customers comparing basic 26L options

• homes where premium features are not required

Why it ranks highly

Dux is a recognised hot water brand, and a basic 26L continuous flow system can suit the right home when installed correctly.

It is a practical comparison point for customers looking beyond Rinnai and Rheem.

Things to consider

Check warranty, support, flow rate suitability and installation requirements. A basic unit can be good value, but only when matched correctly to the home.

Best Off-Grid or Outdoor Lifestyle Option: Onsen 26

The Onsen 26 is more of a niche option than a mainstream family-home recommendation.

Best for

• off-grid setups

• camping-style applications

• cabins or remote use cases

• properties where standard residential installation may not be the goal

• customers who specifically need a portable or off-grid type solution

Why it ranks

Onsen-style systems are included because some customers search for off-grid hot water options. They can suit specific use cases where a standard installed residential continuous flow system is not the right fit.

Things to consider

For normal Brisbane or Gold Coast family homes, a fully installed residential continuous flow system is usually the better comparison.

Quick comparison: 2025 continuous flow gas hot water awards

What size continuous flow gas hot water system do you need?

Flow rate is one of the most important decisions when choosing continuous flow gas hot water.

JR Gas & Water’s instant gas category separates systems by bathroom suitability, including 10–13L for 1 bathroom, 16L for 1 bathroom, 20L for 2 bathrooms, 26L for 3 bathrooms and 32L for 4 bathrooms. (JR Gas and Water)

General sizing guide

• 10L to 13L can suit very small applications

• 16L can suit many one-bathroom homes

• 20L can suit some two-bathroom homes

• 26L can suit many family homes

• 32L can suit larger homes with stronger demand

The right size depends on:

• number of bathrooms

• number of people in the home

• gas type

• gas pipe sizing

• water pressure

• distance to fixtures

• incoming water temperature

• whether multiple showers run at once

• whether kitchen and laundry demand overlaps with shower use

Do not choose by litres per minute alone. A 26L unit still needs a suitable gas supply and proper installation conditions.

Continuous flow gas vs gas storage hot water

A continuous flow system heats water on demand. A gas storage hot water system stores heated water in a tank.

Continuous flow gas may suit if:

• you want hot water on demand

• you prefer a compact wall-mounted system

• you do not want a storage tank

• the home has suitable gas supply

• the current continuous flow unit is due for replacement

• you want a modern gas hot water setup

Gas storage may suit if:

• the home already has gas storage

• you want a straightforward like-for-like replacement

• the gas supply may not suit a high-flow continuous unit

• upfront cost matters

• the property is a rental

• the household prefers stored hot water

If your old gas storage system has failed, do not automatically switch to continuous flow without checking the gas supply and installation cost.

Continuous flow gas vs heat pump hot water

For many homes, the bigger question is whether to stay with gas at all.

A heat pump hot water system uses electricity and ambient air to heat stored water more efficiently than standard electric storage. It can be a strong option for homes wanting to reduce gas use.

Continuous flow gas may suit if:

• the home already has natural gas or LPG

• you want instant hot water on demand

• the existing unit is continuous flow

• you prefer compact wall-mounted installation

• upfront installed cost matters

• the home is not suitable for a heat pump

Heat pump hot water may suit if:

• you want to reduce gas use

• you have solar PV

• long-term running cost matters

• the home has suitable outdoor space

• you are replacing an old electric or gas system

• you want an efficient stored hot water option

Both can be good choices. The right answer depends on the home.

Key factors to compare before buying

1. Flow rate in L/min

Flow rate tells you how much hot water the unit can produce under test conditions. Higher flow rates generally suit larger homes, but only if the gas supply and installation support the unit.

2. Gas type

Continuous flow systems are usually sold in natural gas or LPG versions. Make sure the correct model is selected.

Natural gas and LPG units are not the same thing. If you need LPG, say so before ordering.

3. Gas pipe sizing

This is one of the most common issues with continuous flow upgrades.

A larger unit may need more gas than the old system. If the gas pipe is undersized, the unit may not perform correctly or the job may need a gas upgrade.

4. External vs internal installation

Most residential continuous flow units are installed externally.

Internal installations need proper flueing, ventilation and model suitability. If your current system is inside, request a custom quote.

5. Temperature control

Some homes need temperature controllers or specific temperature-limited models.

This can matter for families, rental properties, bathrooms, kitchens and user convenience.

6. Warranty and support

Compare warranty carefully. Look at:

• heat exchanger warranty

• parts warranty

• labour warranty

• controller warranty

• service conditions

• installer support

• parts availability

A longer headline warranty does not always mean every part is covered for the same length of time.

7. Installation package

The installed price can change significantly depending on what is already at the property.

Installation may include or require:

• mounting the new unit

• hot and cold water connections

• gas connection

• valve upgrades

• tempering valve

• power point

• gas main upgrade

• relocation

• old unit removal

• commissioning and testing

• QBCC Form 4 where required

JR Gas & Water’s Rinnai B26 page shows package levels for different replacement and upgrade scenarios, including like-for-like swaps, pipework alterations, gas main upgrades, power point installation and relocation packages. (JR Gas and Water)

Brisbane and Gold Coast installation considerations

Continuous flow gas hot water systems are common across Brisbane, Logan, Ipswich, Redlands, Moreton Bay and the Gold Coast.

Common local factors include:

• older gas pipework that may be undersized

• homes changing from gas storage to continuous flow

• LPG setups on acreage or semi-rural properties

• townhouses with tight wall space

• Queenslanders with long pipe runs

• rental properties needing practical replacements

• coastal corrosion around Gold Coast homes

• homes where the hot water unit is far from bathrooms

• older external units without modern valves or compliant setup

A good continuous flow installation is not just about putting a new unit on the wall. It is about making sure the selected system suits the gas supply, plumbing layout and real household demand.

What can go wrong if the wrong system is chosen?

Choosing the wrong continuous flow gas hot water system can create frustrating problems.

Common issues include:

• water not getting hot enough

• temperature fluctuation during showers

• poor performance when two outlets run together

• long wait times for hot water

• gas supply errors

• unit cutting in and out

• choosing a 16L unit for a family home

• choosing a 26L unit where the gas line cannot support it

• paying for premium features that do not solve the real problem

• installing the unit too far from key fixtures

Many of these problems can be avoided by choosing the system and installation package together.

What you can check before booking

Before requesting a quote or ordering a replacement, gather a few details.

Helpful information includes:

• photos of the current hot water system

• model number and brand

• gas type: natural gas or LPG

• number of bathrooms

• number of people in the home

• whether multiple showers run at once

• whether hot water temperature fluctuates

• whether the existing unit is internal or external

• photos of pipework and gas connection

• distance from unit to bathrooms

• whether controllers are installed

• suburb and access details

These details help JR Gas & Water recommend a system that suits the home rather than guessing from litres per minute alone.

Cost factors for continuous flow gas hot water systems

The installed cost depends on the system selected and the work required.

Cost can be affected by:

• brand and model

• flow rate

• natural gas or LPG

• existing system type

• like-for-like replacement vs conversion

• gas pipe sizing

• valve upgrades

• water pipe alterations

• power point requirements

• tempering valve requirements

• controller installation

• flueing if internal

• relocation

• old unit removal

• access

• urgency

For clearer pathways, browse instant gas hot water systems, check service work pricing, or use Request Quote for non-standard work.

Maintenance tips for continuous flow gas hot water systems

Continuous flow gas systems need basic maintenance to stay safe and reliable.

Good maintenance includes:

• keeping the area around the unit clear

• checking for error codes

• watching for temperature fluctuation

• checking for visible corrosion

• keeping vents and clearances unobstructed

• not covering or enclosing the unit

• arranging professional servicing when needed

• having gas issues checked by a licensed gas fitter

• checking controllers if fitted

• not ignoring repeated ignition or flame failure faults

Do not open, modify or repair gas components yourself. Gas work should always be handled by a licensed gas fitter.

When should you repair instead of replace?

Replacement is not always necessary.

Repair may make sense if:

• the system is not too old

• the fault is minor

• parts are available

• the heat exchanger is sound

• the system still suits the household

• the repair cost is reasonable

Replacement may make sense if:

• the system is old

• faults keep returning

• parts are hard to source

• the unit is undersized

• temperature fluctuates regularly

• the system is badly corroded

• the household has outgrown it

• a gas upgrade or relocation makes replacement more sensible

JR Gas & Water can help with hot water repairs and servicing or replacement advice if your current unit is no longer worth repairing.

What JR Gas & Water can help with

JR Gas & Water helps homeowners, landlords, property managers and businesses compare, repair, replace and install hot water systems across Brisbane, the Gold Coast and nearby South East Queensland areas.

Depending on the job, JR Gas & Water can help with:

• instant gas hot water systems

• Rinnai B26 installation

• Rinnai Infinity 26 installation

• Rheem 26 installation

• Vulcan DUOMAX 26 installation

• gas storage hot water systems

• heat pump hot water systems

• hot water repairs and servicing

• gas fitting

• gas pipe sizing checks

• LPG and natural gas selection

• replacement advice from photos and model numbers

• custom quotes for non-standard installations

Related JR Gas & Water services

• Instant Gas Hot Water Systems

• Rinnai B26 Instant Gas Hot Water System

• Rinnai Infinity 26 Instant Gas Hot Water System

• Rheem 26 Instant Gas Hot Water System

• Vulcan DUOMAX 26 Instant Gas Hot Water System

• Gas Storage Hot Water Systems

• Heat Pump Hot Water Systems

• Hot Water Repairs and Servicing

• Gas Fitting

• Service Work Pricing

• Request Quote

FAQs

What is the best continuous flow gas hot water system in 2025?

For many standard family homes, the Rinnai B26 is the best overall choice because it gives a strong balance of 26L/min performance, value, brand support and everyday reliability.

The best system for your home still depends on gas supply, number of bathrooms, simultaneous hot water use, installation location and budget.

Is Rinnai B26 better than Rinnai Infinity 26?

The Rinnai B26 is often the better value choice for standard homes. The Rinnai Infinity 26 is the better premium option for homeowners who want a higher-end Rinnai system.

If you want strong value, start with the B26. If you want premium positioning, compare the Infinity 26.

Is Rheem 26 a good continuous flow gas hot water system?

Yes, the Rheem 26 can be a good choice for homeowners who want a recognised hot water brand and a practical 26L-class continuous flow system.

It is worth comparing against the Rinnai B26, Rinnai Infinity 26 and Vulcan DUOMAX 26 before choosing.

Is 26L enough for a family home?

A 26L continuous flow gas system can suit many family homes, but it depends on the number of bathrooms, occupants, gas supply and whether multiple hot water outlets run at the same time.

For larger homes or heavy simultaneous use, sizing should be checked carefully before ordering.

Can continuous flow gas hot water run two showers at once?

Some 26L systems may support two showers depending on flow rates, incoming water temperature, gas supply and household setup.

The system still needs to be correctly sized, and the gas pipework must be suitable.

Is continuous flow gas better than gas storage?

Continuous flow gas can be better if you want on-demand hot water, a compact wall-mounted unit and no storage tank.

Gas storage can be better if you want a simpler like-for-like replacement and the existing setup already suits a tank system.

Should I choose instant gas or heat pump hot water?

Choose instant gas if your home already has suitable gas supply and you want on-demand hot water from a compact wall-mounted unit.

Choose heat pump hot water if you want to reduce gas use, have suitable outdoor space, and care more about long-term energy efficiency than lowest upfront cost.

Can I install a continuous flow gas hot water system myself?

No. Continuous flow gas hot water systems must be installed by licensed professionals.

They involve gas, water, combustion, clearances, commissioning and sometimes electrical work. Incorrect installation can be unsafe and may cause poor performance.

Need help choosing the best continuous flow gas hot water system?

If your old instant gas hot water system is failing, undersized or due for replacement, JR Gas & Water can help compare suitable options for your home.

Browse instant gas hot water systems, compare the Rinnai B26, or send photos and model details through for a custom recommendation.

Request a quote from JR Gas & Water