Instant Gas Hot Water Size Guide: 16L vs 20L vs 26L Systems

Jun 26, 2026

Choosing the right instant gas hot water size is important because bigger is not always better. A 26L unit may suit some two-bathroom homes, but it will not perform properly if the gas pipe sizing, water pressure or installation setup cannot support it. A 16L unit may be perfectly suitable for some smaller homes, but it may struggle if multiple showers run at the same time.

Instant gas hot water systems are usually sized by flow rate in litres per minute. Common sizes include 16L, 20L and 26L classes. The right size depends on household demand, number of bathrooms, shower flow rates, gas type, gas pipe sizing, water pressure, distance to outlets, controller requirements and whether the system is replacing another instant gas unit, gas storage, electric storage or heat pump hot water.

This guide explains how to compare 16L, 20L and 26L instant gas hot water systems before ordering.

You can compare Instant Gas Hot Water Systems, Gas Hot Water Systems, broader Hot Water Systems, Electric Hot Water Systems, Heat Pump Hot Water Systems, Instant Electric Systems and Installation Add-Ons online with Installed Today.

Quick answer: what size instant gas hot water system do I need?

As a general starting point:

Instant gas size	Common household fit
16L instant gas	Smaller homes, one-bathroom homes, one shower at a time
20L instant gas	Small to medium homes, moderate use, one to two bathroom homes depending on demand
26L instant gas	Larger homes, two-bathroom homes and higher demand where gas and water supply support it

This is only a guide. The right instant gas size depends on real hot water use and whether the property can support the selected unit.

A larger L/min rating does not automatically mean better hot water. Instant gas systems need suitable gas pipe sizing, water pressure and flow to perform properly.

What does 16L, 20L or 26L mean?

The litre rating on an instant gas hot water system usually refers to the amount of hot water the unit can deliver per minute under specific test conditions.

Common examples include:

16L per minute
20L per minute
26L per minute

This does not mean every home will get the full rated flow at every tap. Real-world performance depends on:

Incoming water temperature
Desired outlet temperature
Shower head flow rate
Water pressure
Gas pipe sizing
Gas type
Distance from unit to outlets
Whether multiple outlets run at once
Unit settings
Installation quality

A 26L unit on poor gas supply may perform worse than expected.

Why instant gas sizing matters

Instant gas hot water systems heat water on demand. They do not store hot water in a tank.

Sizing matters because the system needs to keep up with the water flowing through it when hot water is being used.

If the unit is too small, you may notice:

Temperature fluctuations
Poor performance with multiple outlets
Difficulty running two showers
Hot water dropping when another tap turns on
Lower comfort during peak use
More customer complaints in rentals or short-stay homes

If the unit is too large for the property, you may pay more upfront without gaining better performance if the gas and water supply cannot support it.

Instant gas sizing is not the same as storage sizing

Storage hot water systems are usually sized by tank capacity.

Instant gas systems are sized by flow rate.

This means a 250L gas storage tank and a 26L instant gas unit are not directly comparable.

A storage tank holds heated water ready for use.

An instant gas unit heats water as it flows through the unit.

This is why sizing must consider simultaneous use, shower flow rates, gas supply and water pressure.

16L instant gas hot water systems

A 16L instant gas hot water system may suit smaller homes with lower hot water demand.

It may suit:

One-bathroom homes
Smaller households
One to two people
Homes where one shower runs at a time
Low-to-moderate hot water use
Some units or townhouses where gas setup suits
Customers replacing an existing 16L unit that performed well
Properties with suitable gas pipe sizing and water pressure

A 16L unit may not suit:

Larger families
Two showers running at once
High-flow shower heads
Homes with multiple bathrooms
Heavy bath use
Short-stay accommodation
High guest demand
Homes where the old 16L system struggled

A 16L instant gas unit can be practical, but it should not be chosen for a high-demand household just to reduce upfront cost.

16L instant gas: best-fit examples

A 16L instant gas system may be a good fit for:

A single-person home
A couple with one bathroom
A small townhouse
A small rental with moderate use
A one-shower home with sensible flow rates
A like-for-like replacement where the old 16L unit worked well

Before choosing 16L, check whether the household expects more than one hot outlet to run at the same time.

20L instant gas hot water systems

A 20L instant gas hot water system is often compared by small to medium households.

It may suit:

Two to three person homes
One to two bathroom homes with moderate use
Homes where one shower is usually used at a time
Some homes with occasional overlapping demand
Properties replacing an existing 20L unit
Homes with suitable gas pipe sizing
Homes with suitable water pressure
Customers wanting more capacity than a 16L unit

A 20L unit may not suit:

Larger families with heavy demand
Homes regularly running two showers at once
High-flow shower setups
Larger rentals
Short-stay homes with high guest occupancy
Properties where gas pipe sizing is unsuitable

A 20L instant gas unit can be a practical middle ground, but site suitability still matters.

20L instant gas: best-fit examples

A 20L instant gas system may suit:

A small family
A two-person home with higher shower demand
A three-person household with moderate use
A one-bathroom home wanting extra capacity
A two-bathroom home where showers are not usually simultaneous
A like-for-like replacement of an existing 20L system

Before choosing 20L, check shower habits, water pressure and gas pipe sizing.

26L instant gas hot water systems

A 26L instant gas hot water system is often compared by larger households and two-bathroom homes.

It may suit:

Larger families
Two-bathroom homes
Homes with higher hot water demand
Homes where two showers may run close together
Properties replacing an existing 26L unit
Customers wanting stronger continuous flow capacity
Homes with suitable gas pipe sizing
Homes with suitable water pressure

A 26L unit may not suit:

Homes with undersized gas pipework
Homes with poor water pressure
Low-demand households that do not need the extra capacity
Properties where the larger unit adds cost without benefit
Installations where electrical power or mounting requirements are not suitable

A 26L instant gas system can be a strong option, but only where the property can support it.

26L instant gas: best-fit examples

A 26L instant gas system may suit:

A family of four
A two-bathroom home
A larger rental property
A home replacing an old 26L unit
A household with higher peak shower demand
A property with suitable natural gas or LPG supply
A property with suitable water pressure

Before choosing 26L, confirm gas pipe sizing, gas type, water pressure, power requirements and installation clearances.

16L vs 20L instant gas

Choose 16L where:

The home has one bathroom
One shower is usually used at a time
Household demand is modest
The existing 16L system performed well
Lower upfront product cost matters
Gas and water setup supports the selected unit

Choose 20L where:

The household wants more capacity than 16L
There are two to three people
Shower demand is moderate
Guest use is occasional
There is one bathroom or light two-bathroom use
The old 16L unit was borderline

The difference between 16L and 20L can matter where the household has higher shower demand but does not need a full 26L unit.

20L vs 26L instant gas

Choose 20L where:

The home has moderate demand
One shower is usually used at a time
There are one to two bathrooms but limited simultaneous use
Gas pipe sizing is suitable for the model
The old 20L system performed well
Lower upfront product cost matters

Choose 26L where:

The home has higher demand
There are two bathrooms
Two showers may run close together
The household has more people
The old 20L system struggled
Gas pipe sizing and water pressure support the larger unit

A 26L system is not automatically the best choice. It should be selected because the household needs it and the property can support it.

16L vs 26L instant gas

The gap between 16L and 26L is significant.

A 16L system may suit smaller one-bathroom homes.

A 26L system may suit larger two-bathroom homes where gas and water supply are suitable.

Do not jump from 16L to 26L without checking:

Household demand
Gas pipe sizing
Water pressure
Existing system performance
Shower flow rates
Installation requirements
Whether 20L is the better middle option

The right size is the unit that matches actual demand, not the largest model available.

Instant gas sizing for 1 person

A one-person home may suit:

16L instant gas where gas supply suits
20L instant gas if higher demand or future use is expected
Electric storage where gas is not suitable
Heat pump hot water where the site suits and stored hot water is preferred

For one person, avoid oversizing unless there is a clear reason such as guest use, high-flow fixtures or future household changes.

Instant gas sizing for 2 people

A two-person household may compare:

16L instant gas for modest one-bathroom use
20L instant gas for higher shower demand
26L only where there is a genuine need and the property supports it

Check shower length, guest use, number of bathrooms and whether the existing system struggled.

Instant gas sizing for 3 people

A three-person home may compare:

20L instant gas for moderate use
26L instant gas for higher demand or two-bathroom homes
Gas storage where stored hot water is preferred
Heat pump hot water if moving away from gas

Sizing depends on whether showers overlap and whether the gas pipework can support the selected unit.

Instant gas sizing for 4 people

A four-person household may compare:

20L instant gas for moderate one-shower-at-a-time use
26L instant gas for higher demand
Gas storage where stored hot water suits better
Heat pump hot water where the site suits and electric upgrade is preferred

A 26L system is often worth comparing for four-person homes, but gas pipe sizing and water pressure must be confirmed.

Instant gas sizing for 5 or more people

Larger households should be assessed carefully.

Options may include:

26L instant gas where gas and water supply support it
Larger or custom hot water design where demand is very high
Gas storage where stored hot water suits
Heat pump hot water where the site suits
Alternative designs for multiple bathrooms and high peak demand

Check:

Number of showers per day
Whether showers overlap
Bath use
High-flow shower heads
Gas pipe sizing
Water pressure
Existing system performance
Household expectations

Large households should not be sized from litres per minute alone.

Instant gas sizing for one bathroom

One-bathroom homes may suit 16L or 20L systems depending on demand.

Check:

Number of people
Shower length
Shower head flow rate
Bath use
Kitchen and laundry hot water use
Whether guests stay often
Existing unit size
Whether the old system struggled

A one-bathroom home with two people may suit 16L or 20L. A one-bathroom home with four people may need more careful checking.

Instant gas sizing for two bathrooms

Two-bathroom homes usually need more careful sizing.

Check:

Whether two showers run at once
Shower head flow rates
Water pressure
Gas pipe sizing
Number of people
Bath use
Morning peak demand
Evening peak demand
Distance from unit to bathrooms

A 26L instant gas unit may suit some two-bathroom homes, but only where the property can support it.

Instant gas sizing for homes with baths

Baths can create heavy hot water demand.

Before choosing instant gas for a home with a bath, check:

Bath size
How often the bath is used
Whether showers run at the same time
Whether the unit can fill the bath at a practical rate
Gas pipe sizing
Water pressure
Flow rate expectations
Household demand

Some homes with baths may still prefer stored hot water depending on usage.

Instant gas sizing for high-flow shower heads

High-flow shower heads can affect instant gas performance.

They can increase demand by requiring more hot water per minute.

Before choosing a larger instant gas unit, check:

Shower head flow rate
Number of showers
Whether showers overlap
Gas pipe sizing
Water pressure
Whether lower-flow fixtures would improve performance
Whether the existing system was undersized or the fixture demand is too high

A bigger unit may not solve performance issues if water pressure or gas supply is the limitation.

Instant gas sizing and gas pipe sizing

Gas pipe sizing is one of the most important instant gas sizing factors.

A larger unit usually needs more gas supply.

Gas pipe sizing depends on:

Pipe diameter
Pipe length
Gas type
Gas meter or LPG setup
Other gas appliances
Appliance gas load
Installation location
Compliance requirements

A licensed gas fitter should confirm whether the existing gas pipework supports the selected unit.

Instant gas sizing and water pressure

Water pressure affects instant gas performance.

Poor water pressure can cause:

Reduced flow
Poor shower performance
Temperature fluctuation
Difficulty running multiple outlets
Poor user experience
Incorrect assumptions about unit size

If hot water pressure has been poor, diagnose water pressure and pipework before choosing a replacement.

Instant gas sizing and natural gas

Natural gas may suit homes already connected to a suitable natural gas supply.

Before choosing a natural gas instant system, check:

Existing gas connection
Gas pipe sizing
Gas meter setup
Other gas appliances
Flow rate required
Water pressure
Correct natural gas model
Licensed gas fitting requirements

Natural gas models are not interchangeable with LPG models.

Instant gas sizing and LPG

LPG may suit homes without natural gas where LPG supply is already set up or planned.

Before choosing an LPG instant system, check:

Correct LPG model
LPG bottle location
Regulator setup
Gas pipe sizing
Bottle changeover arrangements
LPG delivery access
Household demand
Water pressure
Licensed gas fitting requirements

LPG and natural gas are different. Always order the correct gas type.

Instant gas sizing and controllers

Some instant gas systems can use temperature controllers.

Controllers may affect the user experience by allowing selected temperature control depending on model and setup.

Before choosing controllers, check:

Unit compatibility
Number of controllers needed
Wiring requirements
Installation location
Household use
Whether controller installation is included
Whether extra electrical or wiring work is required

Controllers can be useful, but they can add cost and should be selected intentionally.

Instant gas sizing and electrical power

Many instant gas systems require electrical power for ignition, fan operation, controls or safety functions depending on model.

Before choosing a system, check:

Whether a power point is nearby
Whether the power point is suitable
Whether a new weatherproof power point is needed
Whether electrical work is included
Whether controller wiring is required
Whether the unit is being relocated

A licensed electrician may be needed depending on the job.

Instant gas sizing and unit location

Location affects instant gas suitability.

Before choosing a size, check:

Outdoor clearances
Distance to bathrooms
Distance to kitchen and laundry
Gas pipe route
Water pipe route
Power availability
Wall mounting
Access for servicing
Nearby windows or doors
Boundary clearances
Weather exposure
Compliance requirements

Do not assume the old location automatically suits a larger replacement unit.

Replacing an existing instant gas unit with the same size

Replacing with the same size may make sense when:

The old system performed well
Household demand has not changed
The flow rate was suitable
Gas pipe sizing supports the unit
Water pressure is suitable
The gas type remains the same
The location is still compliant
The new unit has similar requirements

If the old system struggled, do not automatically choose the same size.

Upgrading from 16L to 20L instant gas

Upgrading from 16L to 20L may make sense where:

The old 16L unit was borderline
The household has grown
Shower use has increased
The home wants better capacity
Gas pipe sizing supports the upgrade
Water pressure supports the upgrade
The installation location suits the new unit

Before upgrading, confirm whether the issue is unit size, gas supply, water pressure or fixture flow.

Upgrading from 20L to 26L instant gas

Upgrading from 20L to 26L may make sense where:

The home has higher demand
Two showers may run close together
The household has grown
The old 20L unit struggled
Gas pipe sizing supports 26L
Water pressure supports 26L
The location suits the larger unit

A 26L upgrade should be checked carefully because gas pipework upgrades may be needed.

Replacing gas storage with instant gas

Changing from gas storage to instant gas is not always a simple swap.

Before changing, check:

Gas pipe sizing
Water pressure
Power point availability
Outdoor mounting location
Pipework changes
Old tank removal
Disposal
Controller requirements
Household demand
Compliance requirements

Gas storage and instant gas use gas differently. A home that supported gas storage may still need checks before installing instant gas.

Replacing electric storage with instant gas

Changing from electric storage to instant gas can be more complex.

You may need:

Natural gas or LPG supply
New gas pipework
Licensed gas fitting
Outdoor location
Water pipework changes
Electrical disconnection or changes
Power point for the gas unit
Old electric tank removal
Disposal
Compliance upgrades

If the property does not already have suitable gas, compare Heat Pump Hot Water Systems before committing to a gas conversion.

Instant gas vs heat pump sizing

Instant gas and heat pump hot water are sized differently.

Instant gas sizing depends on:

Flow rate
Gas pipe sizing
Water pressure
Gas type
Simultaneous use

Heat pump sizing depends on:

Tank capacity
Recovery rate
Timer settings
Outdoor airflow
Condensate drainage
Boost mode
Household demand

Choose instant gas if the home has suitable gas and continuous flow is preferred.

Choose heat pump if the home suits efficient electric stored hot water.

Instant gas vs gas storage sizing

Instant gas and gas storage both use gas, but they deliver hot water differently.

Instant gas may suit:

Compact wall-mounted installation
Continuous flow hot water
Homes with suitable gas pipe sizing
Homes with suitable water pressure
Customers wanting no storage tank

Gas storage may suit:

Homes already using gas storage
Stored hot water preference
Properties where storage tanks suit the location
Households wanting familiar tank-style hot water
Sites where instant gas pipe sizing is difficult

Compare Gas Hot Water Systems if stored gas hot water may be the better fit.

Instant gas vs instant electric sizing

Instant gas and instant electric both heat water on demand, but they use different energy sources.

Instant gas may suit:

Homes already using natural gas or LPG
Whole-home continuous flow where gas supply supports it
Higher hot water demand
Properties with suitable water pressure

Instant electric may suit:

Point-of-use applications
Small fixtures
Low-demand areas
Compact spaces
Homes or rooms without gas
Properties with suitable electrical capacity

For whole-home use, instant gas is often more commonly compared than instant electric, but only where gas supply is suitable.

Instant gas sizing for rentals

Rental properties should be sized for likely occupancy, not just the current tenant.

Check:

Number of bedrooms
Number of bathrooms
Likely tenant count
Past hot water complaints
Existing system size
Gas type
Gas pipe sizing
Water pressure
Maintenance access
Simplicity for tenants

A rental system that is too small can create repeat complaints.

Instant gas sizing for Airbnb and short-stay homes

Short-stay homes can have high peak demand.

Before choosing instant gas, check:

Maximum guest count
Number of bathrooms
Whether showers overlap
Bath use
Laundry between bookings
Guest expectations
Gas pipe sizing
Water pressure
Controller settings
Maintenance access

A short-stay property may need a larger system than an owner-occupied home with the same number of bedrooms.

Instant gas sizing for renovations

A renovation is a good time to size instant gas properly.

Before choosing, confirm:

Final bathroom count
Shower locations
Bath use
Kitchen and laundry locations
Gas pipe route
Water pipe route
Power point location
Outdoor unit location
Controller locations
Access after renovation
Compliance requirements

Do not leave instant gas sizing until after pipework and electrical locations are locked in.

Instant gas sizing for units and townhouses

Units and townhouses may have extra constraints.

Before choosing instant gas, check:

Body corporate or strata rules
Gas availability
Natural gas or LPG setup
Outdoor unit location
Clearances
Flue or ventilation issues where relevant
Power availability
Water pressure
Access
Noise and neighbour considerations
Compliance requirements

Do not assume a house-style instant gas installation applies to a unit or townhouse.

Brand options for instant gas hot water

Installed Today lists several homepage-linked hot water brands that customers commonly compare for gas, instant gas and broader hot water replacement.

Brands worth comparing include:

Compare brands by gas type, flow rate, dimensions, warranty, controller options and installation requirements.

Rinnai instant gas sizing

Rinnai Hot Water Systems are commonly compared for instant gas and continuous flow hot water.

When sizing Rinnai instant gas systems, check:

Flow rate class
Natural gas or LPG
Gas pipe sizing
Water pressure
Number of bathrooms
Shower habits
Power requirements
Controller options
Installation location

A Rinnai 26L-style option may suit some two-bathroom homes, but only where gas and water supply support it.

Rheem instant gas sizing

Rheem Hot Water Systems are commonly compared across gas storage, instant gas, electric and heat pump options.

When sizing Rheem gas options, check:

Instant gas or gas storage
Flow rate or tank capacity
Natural gas or LPG
Household demand
Gas pipe sizing
Water pressure
Location
Warranty terms

Choose by system type and suitability, not brand name alone.

Bosch instant gas sizing

Bosch Hot Water Systems are often compared for gas hot water and continuous flow options.

When sizing Bosch gas systems, check:

Flow rate
Gas type
Ignition requirements
Water pressure
Gas pipe sizing
Household demand
Installation location
Model compatibility

Bosch gas options should be matched carefully to the property’s natural gas or LPG setup.

Dux gas hot water sizing

Dux Hot Water Systems are commonly compared for electric, gas and broader hot water replacement.

When sizing Dux gas options, check:

Gas storage or instant gas pathway
Tank size or flow rate
Gas type
Household demand
Installation location
Water pressure
Warranty terms

Dux may suit customers comparing mainstream hot water brands across multiple system types.

Aquamax gas hot water sizing

Aquamax Hot Water Systems are often compared for gas storage and hot water replacement.

When sizing Aquamax gas systems, check:

Storage capacity
Natural gas or LPG
Household size
Number of bathrooms
Existing system performance
Installation location
Recovery expectations

If stored gas hot water is preferred, Aquamax may be worth comparing against instant gas options.

Vulcan gas hot water sizing

Vulcan Hot Water Systems may suit customers comparing value-focused hot water replacement.

When sizing Vulcan systems, check:

System type
Tank capacity where relevant
Household demand
Gas type where relevant
Installation requirements
Warranty terms
Total replacement pathway

A lower upfront product cost should still be balanced against correct sizing.

Installation Add-Ons and instant gas sizing

Installation Add-Ons may be relevant where an instant gas replacement needs extra selected work or components.

Add-ons may relate to:

Valves
Disposal
Electrical work
Gas work
Pipework changes
Controller wiring
Access issues
Other installation-related needs where available

The right instant gas size still needs the right installation pathway.

Supply-only instant gas sizing checks

Supply-only ordering can suit customers who already have their own licensed gas fitter or plumber arranged.

Before ordering supply only, confirm:

Correct flow rate
Correct gas type
Correct product dimensions
Suitable gas pipe sizing
Suitable water pressure
Suitable power supply
Suitable installation location
Suitable clearances
Whether controllers are required
Whether old unit removal is arranged
Whether disposal is arranged
Whether valves or add-ons are needed

Supply-only product pricing generally does not include installation, valves, old unit removal, disposal, gas work, pipework changes, electrical work, controller wiring, drainage, access upgrades or compliance upgrades unless clearly selected or included.

Supplied-and-installed instant gas sizing checks

Supplied-and-installed options may be available on selected products in eligible Brisbane and Gold Coast service areas where shown.

Before ordering supplied and installed, check:

Service area eligibility
Existing system type
Current unit size
Household demand
Product suitability
Installation inclusions
Natural gas or LPG
Gas pipe sizing
Water pressure
Electrical work
Controller requirements
Valve requirements
Old unit removal
Disposal
Pipework changes
Access
Compliance upgrades

Do not assume every site requirement is included. Check the selected product and installation options carefully.

Common mistake: choosing the biggest L/min rating

A larger flow rate is not automatically better.

A 26L unit may not perform properly if gas pipe sizing or water pressure is unsuitable.

Common mistake: choosing the same size after poor performance

If the old system struggled, replacing it with the same size may repeat the issue.

Check whether the problem was unit size, gas supply, water pressure, pipework or fixture flow.

Common mistake: ignoring gas pipe sizing

Instant gas systems depend heavily on gas supply.

A larger unit may need gas pipework upgrades.

Common mistake: ignoring water pressure

Water pressure affects flow and user experience.

Poor water pressure should be diagnosed before choosing a replacement.

Common mistake: choosing the wrong gas type

Natural gas and LPG are different.

Always confirm the property gas type and order the correct model.

Common mistake: assuming instant gas means instant hot water at the tap

Instant gas means the unit heats water on demand.

It does not mean hot water reaches every tap instantly. Pipe length still affects wait time.

Common mistake: switching from gas storage to instant without checks

Gas storage to instant gas can be a good upgrade, but it may require gas pipework, power, mounting, pipework changes and compliance checks.

Common mistake: DIY instant gas installation

Instant gas hot water installation must be completed by a licensed gas fitter or suitable licensed professional.

DIY gas work can create:

Gas leaks
Carbon monoxide risk
Fire risk
Water leaks
Scalding risks
Warranty problems
Insurance issues
Non-compliant work
Poor performance
Serious safety hazards

Use the right licensed professional.

Final verdict: should you choose 16L, 20L or 26L instant gas?

Choose a 16L instant gas system for smaller one-bathroom homes, modest hot water use and one shower at a time where gas and water supply support the unit.

Choose a 20L instant gas system for small to medium homes, moderate demand, and households wanting more capacity than 16L without necessarily needing a 26L unit.

Choose a 26L instant gas system for larger homes, two-bathroom properties and higher hot water demand where gas pipe sizing, water pressure and installation requirements support the larger flow rate.

Start by comparing Instant Gas Hot Water Systems, Gas Hot Water Systems, broader Hot Water Systems, Electric Hot Water Systems, Heat Pump Hot Water Systems, Instant Electric Systems and Installation Add-Ons.

The best instant gas size is not always the largest unit. It is the system that matches your household demand, gas type, gas pipe sizing, water pressure, installation location and long-term hot water expectations.

Long-tail FAQs

What size instant gas hot water system do I need?

The right instant gas size depends on household size, bathrooms, shower habits, gas type, gas pipe sizing, water pressure and whether multiple outlets run at once.

Is 16L instant gas enough?

A 16L instant gas system may suit smaller one-bathroom homes where one shower runs at a time and demand is modest.

Is 20L instant gas enough for a family?

A 20L instant gas system may suit some small to medium families with moderate use, but higher-demand homes or two-bathroom homes may need 26L where the site supports it.

Is 26L instant gas enough for two bathrooms?

A 26L instant gas system may suit some two-bathroom homes, but only where gas pipe sizing and water pressure support the selected unit.

Should I choose 20L or 26L instant gas?

Choose 20L for moderate use and 26L for higher demand or two-bathroom homes, provided gas supply and water pressure support the larger unit.

Can I replace a 16L instant gas with a 26L unit?

Sometimes, but gas pipe sizing, water pressure, power supply, clearances and installation requirements must be checked before upgrading.

Does a bigger instant gas system use more gas?

A larger unit can use more gas when delivering higher flow. Actual running cost depends on usage, gas price, temperature settings and household demand.