Electric Hot Water System Replacement Cost: Australian Buyer’s Guide

Replacing an electric hot water system can be simple or surprisingly involved depending on the home. A straight swap from one electric storage tank to a similar new model is usually easier than changing size, moving the unit, upgrading electrical supply, switching to instant electric, or changing to heat pump hot water.

For most Australian homes, electric hot water replacement cost depends on the product type, tank size, brand, installation location, electrical setup, valves, access, drainage, old unit removal, disposal and whether any compliance upgrades are required.

This guide explains what affects electric hot water system replacement cost, how standard electric storage compares with instant electric and heat pump hot water, and what to check before ordering.

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

Quick answer: how much does electric hot water replacement cost?

Electric hot water replacement cost depends on whether the job is a simple like-for-like replacement or a more complex upgrade.

As a practical guide:

The product price is only one part of the total replacement cost. The installation pathway can change the final price significantly.

What is an electric hot water system?

An electric hot water system uses electricity to heat water for showers, taps, baths, kitchens and laundries.

The main electric hot water types include:

• Electric storage hot water systems

• Instant electric hot water systems

• Heat pump hot water systems

Standard electric storage systems heat water in a tank using an electric element.

Instant electric systems heat water as it passes through the unit.

Heat pump systems use electricity to transfer heat from surrounding air into stored water.

Each option has different product costs, installation requirements and running cost considerations.

Electric storage hot water replacement cost factors

Electric Hot Water Systems are commonly used for like-for-like replacement jobs.

Cost may be affected by:

• Tank size

• Brand and model

• Indoor or outdoor location

• Existing electrical supply

• Existing plumbing connections

• Valve requirements

• Tempering valve requirements

• Pressure limiting valve requirements

• Expansion control valve requirements where applicable

• Drainage

• Relief valve discharge

• Access

• Base or support condition

• Old unit removal

• Disposal

• Compliance upgrades

A simple replacement in one home may still cost more in another if valves, drainage, electrical work or access are different.

Instant electric hot water replacement cost factors

Instant Electric Systems are usually better suited to specific applications rather than every whole-home replacement.

Cost may be affected by:

• Flow rate requirements

• Temperature rise required

• Electrical capacity

• Switchboard capacity

• Circuit requirements

• Existing wiring

• Water pressure

• Installation location

• Pipework changes

• Access

• Compliance requirements

• Whether the unit is point-of-use or whole-home

Instant electric can be compact, but it can also have high electrical requirements. It should not be chosen without checking whether the property can support it.

Heat pump hot water replacement cost factors

Heat Pump Hot Water Systems are often compared by customers replacing older electric storage systems.

Cost may be affected by:

• Tank size

• Brand and model

• Outdoor airflow

• Condensate drainage

• Electrical setup

• Timer requirements

• Noise placement

• Base or slab condition

• Pipework changes

• Valve requirements

• Old unit removal

• Disposal

• Access

• Compliance upgrades

• Rebate or certificate eligibility where applicable

Heat pump hot water usually has a higher upfront product cost than standard electric storage, but it may use less electricity in suitable conditions.

Electric storage vs instant electric replacement cost

Electric storage and instant electric systems are very different.

For most full-home replacements, electric storage is the more common option. Instant electric should be chosen carefully.

Electric storage vs heat pump replacement cost

Heat pump hot water can be a more efficient electric upgrade, but it is more site-specific.

Choose heat pump hot water if your property has suitable airflow, drainage, electrical setup and noise placement.

Choose electric storage if you need a simpler replacement or if the site does not suit heat pump installation.

Electric hot water vs gas hot water replacement cost

Electric and gas hot water replacement costs depend on the existing setup.

Electric hot water may suit:

• Homes without gas

• Units and townhouses

• Simple electric replacements

• Properties with suitable electrical supply

• Customers wanting storage hot water

• Homes considering heat pump upgrades

Gas hot water may suit:

• Homes already connected to natural gas or LPG

• Existing gas storage replacements

• Existing instant gas replacements

• Homes with suitable gas pipe sizing

• Customers wanting continuous flow gas hot water

Natural gas and LPG are not interchangeable. Any gas hot water work must be completed by a licensed gas fitter.

Compare Gas Hot Water Systems and Instant Gas Hot Water Systems if your home already has gas.

What can make electric hot water replacement cheaper?

Electric hot water replacement is usually more straightforward when:

• The new system is similar to the old system

• The tank stays in the same location

• The tank size is similar

• Existing pipework is suitable

• Electrical supply is suitable

• Access is easy

• Existing drainage is suitable

• Existing base or support is suitable

• Required valves are already compliant and in good condition

• The old unit can be removed easily

• No switchboard or wiring changes are required

• The selected product fits the space

A simple job still needs licensed professionals, but fewer changes usually means fewer cost surprises.

What can make electric hot water replacement more expensive?

Replacement cost can increase when extra work is needed.

Common cost adders include:

• Changing tank size

• Moving the unit

• Difficult access

• Indoor cupboard work

• New drainage

• Drip tray requirements where applicable

• Pipework changes

• Valve replacement

• Tempering valve installation

• Pressure limiting valve installation

• Expansion control valve installation where required

• Electrical upgrades

• Switchboard work

• New circuit or isolator requirements

• Old unit removal

• Disposal

• Base or support upgrades

• Compliance upgrades

• Heat pump condensate drainage

• Heat pump airflow or placement issues

The cheapest unit is not always the cheapest final replacement.

Electric hot water system size and cost

Tank size affects product cost, physical space and suitability.

As a general guide:

The right size depends on daily hot water demand, not just the number of people.

125L electric hot water replacement

A 125L electric hot water system may suit:

• Smaller households

• One to two people

• Units

• Townhouses

• Low-demand homes

• Some rental properties

• Properties with limited space

Before replacing with 125L, check:

• Shower habits

• Bath use

• Guest use

• Off-peak or controlled-load setup

• Whether the old system ran out

• Access

• Indoor or outdoor location

A 125L system can be practical, but it may be too small for higher-demand homes.

160L electric hot water replacement

A 160L electric hot water system may suit:

• Two-person homes

• Some small families with moderate use

• Units and townhouses

• Homes needing more capacity than 125L

• Low-to-moderate shower demand

Before choosing 160L, check whether the household uses long showers, has a bath, or often has guests.

250L electric hot water replacement

A 250L electric hot water system is commonly compared for many 3 to 4 person households.

It may suit:

• Family homes

• Rentals

• One or two bathroom properties

• Homes with moderate hot water use

• Like-for-like replacements where the old 250L system performed well

Before replacing with another 250L tank, check whether the old system ran out regularly. If it did, the same size may repeat the problem.

315L electric hot water replacement

A 315L electric hot water system may suit larger households or higher-demand homes.

It may be considered for:

• Larger families

• Homes with more bedrooms

• Homes with back-to-back showers

• Some rental properties

• Properties with higher peak demand

• Homes where off-peak heating requires more stored capacity

Check space, access, base support and electrical setup before ordering.

400L electric hot water replacement

A 400L electric hot water system may be considered for large households or very high hot water demand.

Before choosing 400L, confirm:

• Number of people

• Number of bathrooms

• Shower use

• Bath use

• Laundry use

• Peak demand

• Space

• Access

• Electrical supply

• Base requirements

• Whether heat pump hot water may be a better long-term option

Bigger tanks cost more and need more room, so choose based on actual demand.

Brand and model cost differences

Brand and model can affect product price, warranty terms, features, dimensions and availability.

Installed Today’s homepage-linked hot water brands include:

• Rheem Hot Water Systems

• Rinnai Hot Water Systems

• Dux Hot Water Systems

• Vulcan Hot Water Systems

• Stiebel Eltron Hot Water Systems

• Aquamax Hot Water Systems

• iStore Hot Water Systems

• Enviroheat Hot Water Systems

• Aquatech / Hydrotherm Hot Water Systems

Compare by system type, capacity, warranty, dimensions, connection positions and installation requirements.

Rheem electric hot water replacement

Rheem Hot Water Systems are commonly compared by customers wanting a major hot water brand.

Rheem may suit:

• Electric storage replacement

• Family-sized systems

• Common Australian replacement sizes

• Customers comparing electric storage and heat pump options

• Supply-only customers with their own installer arranged

• Eligible supplied-and-installed customers where available

Before choosing Rheem, check tank capacity, dimensions, element size, warranty terms and installation requirements.

Rinnai electric hot water replacement

Rinnai Hot Water Systems are often compared across electric storage, heat pump and gas hot water options.

Rinnai may suit:

• Electric storage replacement

• Small to large household sizes depending on model

• Customers comparing Rinnai against Rheem, Dux or Vulcan

• Homes wanting a recognised hot water brand

• Heat pump comparisons where suitable

Before choosing Rinnai, check tank size, connection positions, warranty terms and installation requirements.

Dux electric hot water replacement

Dux Hot Water Systems are commonly compared for electric storage replacements.

Dux may suit:

• Family hot water systems

• Like-for-like electric storage replacement

• Rental properties

• Homes needing common tank sizes

• Customers comparing mainstream hot water brands

Before choosing Dux, check capacity, dimensions, warranty terms, valve requirements and total replacement pathway.

Vulcan electric hot water replacement

Vulcan Hot Water Systems may suit customers looking for value-focused electric hot water replacement.

Vulcan may suit:

• Budget-conscious replacements

• Rental properties

• Simple electric storage needs

• Like-for-like replacement where suitable

• Customers comparing upfront product cost

Before choosing Vulcan, check warranty terms, product dimensions, tank size and total replacement cost.

Stiebel Eltron electric hot water replacement

Stiebel Eltron Hot Water Systems are commonly compared for compact electric, instant electric and premium electric options.

Stiebel Eltron may suit:

• Compact electric applications

• Instant electric comparisons

• Units and small spaces

• Premium electric hot water comparisons

• Homes with specific electrical and space requirements

Before choosing instant or compact electric products, confirm electrical capacity, flow requirements and installation suitability.

Heat pump brands to compare

If you are replacing an electric storage system and want a more efficient electric upgrade, compare heat pump options.

Brands worth comparing include:

• iStore Hot Water Systems

• Rheem Hot Water Systems

• Rinnai Hot Water Systems

• Stiebel Eltron Hot Water Systems

• Enviroheat Hot Water Systems

• Aquatech / Hydrotherm Hot Water Systems

Heat pump suitability depends on outdoor airflow, condensate drainage, electrical setup, noise placement, tank size and recovery.

Basic replacement vs upgrade

A basic replacement usually means replacing an old electric storage system with a similar new electric storage system in the same location.

An upgrade may include:

• Increasing tank size

• Moving the system

• Changing to heat pump hot water

• Changing to instant electric

• Adding timer control

• Changing from electric to gas

• Improving drainage

• Correcting old compliance issues

• Upgrading electrical supply

• Changing from indoor to outdoor installation

Upgrades can be worthwhile, but they usually need more planning.

Like-for-like electric hot water replacement

Like-for-like replacement may suit when:

• The old tank size worked well

• The installation location is suitable

• Electrical supply is suitable

• Pipework is suitable

• Valves are compliant

• Access is easy

• The household demand has not changed

• The customer wants the simplest pathway

Like-for-like is not always best. If the old system ran out, was expensive to run or no longer suits the household, compare alternatives first.

Replacing electric storage with heat pump hot water

Changing from electric storage to heat pump hot water can be a smart upgrade where the property suits.

You may need to check:

• Outdoor airflow

• Condensate drainage

• Noise placement

• Electrical setup

• Timer settings

• Base condition

• Pipework changes

• Space

• Access

• Old unit removal

• Compliance requirements

• Rebate or certificate eligibility where applicable

Heat pumps can use less electricity than standard electric storage in suitable conditions, but they are more site-specific.

Replacing electric storage with instant electric

Changing from electric storage to instant electric needs careful assessment.

You may need to check:

• Electrical capacity

• Switchboard capacity

• Circuit requirements

• Flow rate

• Temperature rise

• Water pressure

• Application type

• Whether it is point-of-use or whole-home

• Installation location

• Compliance requirements

Instant electric should not be chosen just because it is compact. The property must support the electrical and flow requirements.

Replacing electric hot water with gas hot water

Changing from electric to gas can be more complex than replacing electric with electric.

Extra requirements may include:

• Natural gas or LPG confirmation

• Gas pipework

• Licensed gas fitting

• Gas meter or LPG bottle setup

• New unit location

• Water pipework changes

• Electrical disconnection or modification

• Compliance upgrades

• Old unit removal

• Disposal

If the home does not already have suitable gas, compare heat pump hot water before committing to a gas conversion.

Relocating an electric hot water system

Relocating a hot water system can add cost because new plumbing, electrical and drainage work may be required.

Relocation may be considered during:

• Renovations

• Bathroom upgrades

• Laundry remodels

• Outdoor area changes

• Garage conversions

• Unit refits

• Replacing an old indoor cupboard system

• Moving from a tight location to a more serviceable area

Before relocating, check pipe routes, wiring, drainage, access and future serviceability.

Indoor vs outdoor electric hot water replacement

Electric hot water systems may be installed indoors or outdoors depending on the model and site.

Indoor replacement may require:

• Safe drainage

• Drip tray where required

• Cupboard access

• Relief valve discharge

• Space for servicing

• Electrical safety

• Protection from leaks

• Compliance with location requirements

Outdoor replacement may require:

• Stable base

• Weather suitability

• Drainage

• Pipework protection

• Electrical safety

• Access

• Protection from impact

• Future service space

Do not assume the existing location is automatically compliant for a new system.

What is included in electric hot water replacement?

Inclusions vary by product, installer and selected option.

Possible inclusions may include:

• New hot water unit

• Standard connection to existing plumbing

• Basic labour

• Standard commissioning

• Standard valves where included

• Old unit removal where included

• Disposal where included

Do not assume every job includes all valves, pipework changes, electrical work, removal, disposal, drainage or compliance upgrades.

Check the selected product and service details carefully.

What may not be included?

Extra costs may include:

• Tempering valve

• Pressure limiting valve

• Expansion control valve

• Pipework changes

• Electrical circuit work

• Switchboard work

• New isolator

• Timer work

• Drainage changes

• Drip tray

• Concrete base

• Difficult access

• Old unit removal

• Disposal

• Heat pump condensate drainage

• Heat pump electrical upgrades

• Compliance upgrades

• Relocation

This is why two homes replacing the same model can have different total costs.

Maintenance costs after replacement

Electric hot water systems need maintenance to support safe and reliable operation.

Maintenance may include:

• Relief valve checks

• Tempering valve checks

• Leak inspections

• Anode inspection or replacement where applicable

• Electrical checks where required

• Pipework inspection

• Water pressure checks

• Drainage checks

• General system inspection

• Manufacturer-recommended servicing

Do not remove covers, touch wiring, replace elements or modify electrical parts yourself.

Signs your electric hot water system needs replacing

Replacement may be worth considering if the system is:

• Leaking from the tank

• Rusty or corroded

• Frequently tripping power

• Producing inconsistent hot water

• Running out too often

• Making unusual noises

• Very old

• Requiring repeated repairs

• No longer sized for the household

• Expensive to run

• In a poor or non-compliant location

If the cylinder itself is leaking, replacement is often required.

Repair vs replacement cost

Repair may make sense if:

• The system is relatively new

• The tank is not leaking

• The fault is minor

• Parts are available

• Warranty may apply

• The system is still correctly sized

• The installation is otherwise compliant

Replacement may make sense if:

• The tank is leaking

• The system is old

• Repairs are frequent

• Parts are expensive or hard to get

• The system is undersized

• Running costs are high

• You want to upgrade to heat pump hot water

• Electrical or compliance upgrades are needed

• The system no longer suits the household

A licensed professional can help identify whether repair or replacement is the better pathway.

Rebates and incentives

Some energy-efficient hot water systems, including selected heat pump systems, may be eligible for rebates, certificates or incentives depending on product, location, installer, scheme rules and installation pathway.

However, rebate rules can change.

Before relying on any rebate, check:

• Current eligibility

• Product eligibility

• Installer requirements

• State or territory rules

• Documentation requirements

• Whether the price includes an incentive

• Whether the incentive is applied upfront or claimed later

• Whether the old system type affects eligibility

Do not choose a system only because of a rebate. It still needs to suit the home.

Supply-only electric hot water systems

Supply-only ordering can suit customers who already have their own licensed installer arranged.

Supply only may suit:

• Builders

• Renovators

• Landlords

• Property managers

• Trade customers

• Homeowners managing their own installation

• Customers outside supplied-and-installed service areas

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

Before ordering supply only, your licensed installer should confirm the electric hot water system suits the property.

Supplied-and-installed electric hot water systems

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

This can suit customers who want the product and installation pathway arranged together.

Before ordering supplied and installed, check:

• Service area eligibility

• Existing system type

• Installation inclusions

• Electrical work

• Valve requirements

• Old unit removal

• Disposal

• Pipework changes

• Drainage

• Access

• Base or support requirements

• Compliance upgrades

• Product suitability

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

How to reduce electric hot water replacement surprises

Before ordering, collect:

• Photos of the existing unit

• Model number

• Tank size

• Installation location

• Photos of pipework

• Photos of valves

• Access details

• Indoor or outdoor location

• Number of people in the home

• Number of bathrooms

• Whether the old system ran out

• Whether you want storage, instant electric or heat pump

• Whether you want supply only or installed where available

The more accurate the information, the easier it is to avoid choosing the wrong system.

Common mistake: comparing only the product price

The product price is only one part of the total replacement cost.

A cheaper unit can become more expensive if it needs extra valves, electrical work, drainage, pipework changes, access work or compliance upgrades.

Common mistake: choosing the same size after running out

If the old electric system regularly ran out of hot water, replacing it with the same size may repeat the problem.

Reassess household demand before ordering.

Common mistake: ignoring electrical capacity

Electric hot water systems need suitable electrical supply.

Instant electric and heat pump systems in particular should be checked carefully before ordering.

Common mistake: assuming heat pump hot water suits every home

Heat pump hot water can be efficient, but it needs suitable airflow, drainage, electrical setup, service access and noise placement.

A poor location can make a good heat pump perform badly.

Common mistake: assuming instant electric can replace any tank

Instant electric can be useful for selected applications, but whole-home use needs careful flow and electrical checks.

Do not choose it just because it is compact.

Common mistake: ignoring drainage

Hot water systems need safe discharge and drainage.

Heat pumps also create condensate that must be drained properly.

Poor drainage can cause nuisance water, slippery areas or compliance issues.

Common mistake: DIY electric hot water installation

Electric hot water installation can involve plumbing, electrical work, pressure control, scalding safety and compliance.

DIY installation can create:

• Water leaks

• Electrical risks

• Scalding risks

• Warranty issues

• Insurance problems

• Non-compliant work

• Poor performance

• Property damage

Use the right licensed professionals.

Final verdict: how much should you budget for electric hot water replacement?

Electric hot water replacement cost depends on system type, tank size, brand, location, access, valves, drainage, electrical supply, old unit removal, disposal and compliance requirements.

A like-for-like electric storage replacement can be relatively straightforward where the existing setup is suitable and still meets household demand.

Instant electric can suit selected applications but needs careful electrical and flow checks.

Heat pump hot water can be a strong upgrade from standard electric storage where the home has suitable outdoor airflow, condensate drainage, electrical setup and noise placement.

Start by comparing Electric Hot Water Systems, Instant Electric Systems, Heat Pump Hot Water Systems, broader Hot Water Systems, Gas Hot Water Systems and Instant Gas Hot Water Systems.

The best replacement is not always the cheapest system. It is the system that matches your household demand, electrical setup, installation location, budget and long-term running cost goals.

Long-tail FAQs

How much does it cost to replace an electric hot water system?

Electric hot water replacement cost depends on tank size, brand, location, electrical setup, valves, pipework, drainage, access, old unit removal, disposal and whether extra compliance work is required.

Is electric storage cheaper to replace than heat pump hot water?

Electric storage usually has a lower upfront product cost than heat pump hot water, but heat pumps may use less electricity in suitable conditions. The right choice depends on site suitability and long-term goals.

What size electric hot water system do I need?

The right size depends on people, bathrooms, shower habits, bath use, laundry use, timer setup and peak demand. Many 3 to 4 person homes compare 250L systems, but actual usage matters.

Can I replace a 250L electric hot water system with a heat pump?

Yes, where the property suits heat pump installation. Outdoor airflow, condensate drainage, electrical setup, noise placement and access need to be checked first.

Can I replace electric storage with instant electric?

Sometimes, but instant electric has specific electrical and flow requirements. It is often better suited to point-of-use or selected low-demand applications than whole-home replacement.

What adds cost to electric hot water replacement?

Common extras include valves, pipework changes, electrical work, drainage, drip tray requirements, difficult access, old unit removal, disposal, base work and compliance upgrades.

Is a 125L electric hot water system enough?

A 125L system may suit one to two people with moderate use, but it can be too small for longer showers, guest use, baths or higher-demand households.

Is heat pump hot water worth the extra cost?

Heat pump hot water can be worth comparing where the home has suitable outdoor airflow, drainage, electrical setup and noise placement. It may use less electricity than standard electric storage in suitable conditions.

Are rebates available for electric hot water replacement?

Some energy-efficient systems, especially selected heat pumps, may be eligible for rebates or certificates depending on product, location, installer and scheme rules. Check current eligibility before relying on any rebate.

Can I install an electric hot water system myself?

No. Electric hot water installation should be completed by licensed professionals. Plumbing, electrical work, pressure control and compliance requirements can create safety and warranty issues if handled incorrectly.