Hot Water System Cost in Australia [2026]: Installation & Replacement Prices

Replacing a hot water system with the same type typically costs $1,000–$3,000 installed for electric or gas (AUD, prices include GST). Heat pump systems cost $3,000–$6,000 before rebates, and solar $3,500–$8,000. Switching from one type to another adds $400–$2,500 for new electrical circuits, gas lines or relocation.

Here’s what each type costs to buy and install, what a plumber charges for the installation alone, what to do if your system has just failed, and how the running costs change the picture over ten years.

Hot Water System Cost by Type

These are supplied-and-installed prices for a standard household system:

System type	Typical installed cost	Notes
Electric storage	$1,000–$2,800	125 L at the low end; 250–315 L family sizes at the top
Gas storage	$1,200–$2,800
Gas continuous flow	$1,500–$3,000	Also called instantaneous
Heat pump	$3,000–$6,000	Before rebates
Solar (electric or gas boosted)	$3,500–$8,000	Before rebates

Prices include GST (September 2026). The ranges combine published pricing from plumbers in NSW, Adelaide and Brisbane with Yellow Pages’ national cost guide.

What homeowners actually pay sits in the middle of that table. Twenty Adelaide homeowners who shared their hot water replacement costs report a median of $2,100, with most paying between $1,600 and $3,050 (sparky.fyi, 2023–2026). If your quote for a like-for-like electric or gas replacement lands well above $3,000, ask the plumber what’s driving it.

Like-for-Like Replacement vs Switching System Type

The single biggest difference between two hot water quotes is usually whether you’re replacing the same type of system or changing to a different one. The unit is only part of the price; the rest is installation, and that’s where switching costs build up:

Job	Installation cost (labour and fittings, excluding the unit)
Electric to electric (like-for-like)	$400–$800
Gas to gas (like-for-like)	$300–$1,000
Electric to gas	$1,000–$2,000
Any change of technology (new circuit, gas line or relocation)	$400–$2,500
Removal and disposal of the old unit	$150–$400

Figures from South Adelaide Plumbing & Gas, Yellow Pages and The Quote Yard (2026).

A like-for-like swap is cheaper because the connections already exist: the plumber disconnects the old unit, stands the new one in the same spot and reconnects it. Moving from electric to gas means running a gas line; moving from gas to a heat pump usually means a new electrical circuit and sometimes a switchboard check. Relocating the unit adds pipework either way.

Ask for a quote that lists the unit, the installation and the removal of the old system separately. It’s the only way to compare two plumbers fairly, and it shows you straight away whether a higher quote comes from a pricier unit or from more work.

New installations must include a tempering valve, which limits the temperature of water reaching bathrooms. Brisbane plumber Fallon Solutions lists it as a requirement. There’s no published price for it on its own, so check that your quote includes it rather than adding it later.

If Your Hot Water System Has Just Failed

Replace it with the same type. A like-for-like replacement is the fastest and cheapest option, and many plumbers do it the same day. Bunnings, for example, offers same-day and weekend like-for-like replacements at selected stores if you book before 11am.

Switching to a heat pump or solar system while you’re without hot water is rarely quick. It can involve an electrician, rebate paperwork and a unit your plumber doesn’t carry on the van, so it may leave you waiting days.

Before you accept an urgent visit, ask what the plumber charges for after-hours or emergency call-outs. There’s no standard published rate, and it’s the easiest part of an emergency quote to clarify on the phone.

What Changes the Price

Tank size

A bigger household needs more stored hot water, and a bigger tank costs more. Rinnai’s rule of thumb is about 50 litres per person plus an extra 50 litres for peak times: roughly 125 litres for one or two people, 250 litres for three or four, and 315 litres or more for five or more. Continuous flow systems are sized differently, by how many showers and taps you run at once, so ask the installer to size one from your household’s habits.

Location and access

An outdoor unit on the ground is the simplest job. Indoor units need a safety tray and a drain to carry away any leak, and units in a roof space or a tight cupboard take longer to swap. If your old system is somewhere awkward, mention it when you ask for a quote so the price reflects the real job.

Brand

Rheem, Rinnai, Dux, Thermann, Stiebel Eltron and Bosch all sell into the Australian market at different price points. Within the same type and size, the brand usually moves the price less than switching technology does. If you’re comparing brands, compare the warranty on the tank or heating element as well as the price.

Switching technology

See the table above: a change of system type can add up to $2,500 in installation work on top of the unit.

Running Costs by System Type

The cheapest system to buy is often the most expensive to run. RACV compared yearly running costs for a three-person household:

System	Off-peak tariff	Peak tariff
Heat pump	$170	$230
Heat pump with rooftop solar	—	$105–$120
Electric storage	$650	$840
Gas storage	—	$645

On those figures, a heat pump costs around $480 a year less to run than an electric storage system on off-peak power. Over ten years that’s roughly $4,800, enough to cover most or all of the gap in upfront price between the two. Your own numbers will depend on your tariff and household size, but the direction holds: if your system has a long life ahead of it, the running cost matters more than the purchase price.

How Long Does a Hot Water System Last?

Plumbers put typical lifespans at:

• Electric and gas storage: around 8–15 years, with gas storage usually at the shorter end.
• Heat pump: around 10–15 years.
• Continuous flow and solar: up to 20 years or more.

Storage tanks wear out faster because the tank itself eventually corrodes. Regular servicing, including checking the anode and the temperature and pressure relief (TPR) valve, is what gets a system to the upper end of its range. If your storage system is past ten years and starting to leak or run out of hot water early, start pricing a replacement before it fails completely: you’ll have time to compare quotes and consider switching type.

Rebates That Cut the Price

Heat pump and solar systems qualify for federal Small-scale Technology Certificates (STCs), which your installer usually applies as a discount on the quote. Their value isn’t fixed: it depends on your climate zone, the system’s size and the market price of certificates. Recent quotes put the discount anywhere from about $300 to $1,200.

Several states add their own programs on top, including Victoria’s Solar Homes and Victorian Energy Upgrades programs and the NSW Energy Savings Scheme. Amounts and eligibility change often, so check the current figure with your state’s energy agency before you rely on it, and ask the installer to show every rebate as its own line on the quote. Be wary of sellers advertising a single fixed rebate figure: the federal certificate value varies by system and location.

Which Hot Water System Should You Choose?

• Your system has failed and you need hot water now: replace it with the same type.
• You have rooftop solar panels: a heat pump makes the most of the electricity you already generate, and RACV’s figures put its running cost at around $105–$120 a year.
• You already have gas and no plans to go all-electric: gas continuous flow gives you unlimited hot water without a tank, and lasts longer than a storage unit.
• You’re planning ahead and want the lowest cost over ten years: compare a heat pump quote after rebates against a like-for-like replacement, then add the running cost difference.

For more help comparing heating, cooling and hot water options, see our heating and cooling guides.

The Bottom Line

A like-for-like electric or gas replacement costs $1,000–$3,000, and it’s the right call when your system has just failed. If you have time to plan, price a heat pump as well: it costs more upfront but can save hundreds of dollars a year to run. Get two or three quotes that list the unit, the installation and the removal of the old system separately, and check they include a tempering valve.

Frequently asked questions

How much does it cost to install a new hot water system?

A new electric or gas storage system costs $1,000–$2,800 installed, gas continuous flow $1,500–$3,000, a heat pump $3,000–$6,000 before rebates and solar $3,500–$8,000. Switching from one type to another adds $400–$2,500 for new gas lines, electrical circuits or relocation.

How much does it cost to replace a hot water system in Australia?

A like-for-like replacement of an electric or gas system usually costs $1,000–$3,000 including the new unit. Twenty Adelaide homeowners who shared their costs report a median of $2,100.

What is the average labour cost to replace a hot water system?

For a like-for-like swap, the installation alone typically costs $400–$800 for electric and $300–$1,000 for gas, on top of the unit. Removing and disposing of the old unit adds $150–$400 if it isn’t already included.

How much does Bunnings charge to install a hot water system?

Bunnings doesn’t publish a fixed installation price online; it quotes through its stores. Its service covers Dux gas and electric units installed by a licensed plumber, including disconnecting the old system, and is limited to ground-level residential installations, excluding solar, internal gas and in-ceiling units. Extra charges can apply on the day, so compare the total against a local plumber’s quote for the same unit.

Does a plumber or electrician install a hot water system?

A licensed plumber installs the system, and gas units need a licensed gasfitter. If the job needs a new electrical circuit, which is common when switching to a heat pump or from gas to electric, a licensed electrician does that part.

How many years should a hot water system last?

Electric and gas storage systems typically last around 8–15 years, heat pumps 10–15 years, and continuous flow and solar systems up to 20 years or more. Regular servicing helps a system reach the upper end of its range.