Costs, Price Factors and 2026 Rebates
Heat pump hot water cost in Australia: system types, tank sizes and what pushes the price up
What a heat pump water heater costs to supply and install in Australia, how integrated and split units differ, tank sizing, installation extras and incentives.
A heat pump water heater for an Australian household typically costs several thousand dollars installed before incentives, with the final price driven by the type of unit (integrated or split), the tank size, the refrigerant and cold-climate performance, and what has to be removed, re-plumbed or rewired. On this site's illustrative ranges, a 250–315 litre integrated unit replacing an electric storage tank on the same spot might cost about $3,200–$4,800 before incentives, and a premium split unit replacing gas hot water about $4,500–$7,000. Small-scale technology certificates (STCs) reduce almost every quote, and state programs may reduce it further. This guide is part of the installation cost overview.
All prices are illustrative examples, not market rates.
How a heat pump water heater works
A heat pump water heater uses a small refrigeration cycle in reverse. A fan draws outdoor air across an evaporator, the refrigerant absorbs that heat, a compressor raises its temperature, and a heat exchanger transfers the heat into the water in the tank. Because it moves heat rather than making it from electricity directly, it uses a fraction of the electricity of a conventional electric storage tank for the same hot water.
Two physical layouts are common:
- Integrated (all-in-one). The compressor and fan sit on top of the tank. One unit to place, usually cheaper to install, but the fan and compressor noise is wherever the tank is.
- Split. The compressor unit sits separately from the tank, joined by refrigerant or water lines. More flexible for placement and noise, often marketed for cold climates, and usually dearer.
Refrigerants used in heat pump water heaters include R290 (propane), R744 (CO2) and synthetic refrigerants such as R134a. CO2 and some R290 units are marketed for strong performance in cold weather. Ask the installer what refrigerant the model uses and whether refrigerant handling is needed on site (factory-sealed integrated units generally do not need it; some split units do).
Illustrative price ranges
| Scenario (illustrative, incl. GST, before incentives) | Price range |
|---|---|
| Integrated 250–315 L, replacing electric storage in the same place | $3,200–$4,800 |
| Integrated 250–315 L, replacing gas storage (gas capped, new circuit) | $3,800–$5,600 |
| Split or premium cold-climate unit, replacing gas | $4,500–$7,000 |
| Small 150–200 L unit for one or two people | $2,800–$4,200 |
| Extras: tempering valve, new isolator, extra pipe, concrete slab | $150–$900 each, depending on job |
These are site assumptions to show the method. The heat pump worked example shows a full calculation including incentives, and the payback calculator lets you test your own numbers.
Choosing the tank size
Tank size is about the number of people and the pattern of use, not the floor area. Heat pumps recover more slowly than a gas instantaneous unit, so a tank that is too small can run out during back-to-back showers.
| Household | Illustrative tank size people often consider |
|---|---|
| 1–2 people | 150–200 L |
| 3–4 people | 250–315 L |
| 5 or more | 315–400 L |
Treat this as a starting point. A household with long showers or a large bath may need more; one that runs the heat pump in the middle of the day on solar may manage with less because the tank can reheat while people are out. Remember the Small-scale Renewable Energy Scheme only covers air source heat pumps with a capacity under 425 litres.
Installation extras that change the price
- Removing the old system. Disposal of an old tank, and for gas units, capping the gas line by a licensed gasfitter.
- Electrical work. A heat pump needs a suitable circuit. Replacing gas often means running a new circuit from the switchboard, and older switchboards may need work. See switchboard and circuit costs.
- Plumbing. Tempering valve to limit outlet temperature to bathrooms, relief and drain lines, and moving the location if the old spot is unsuitable.
- Base and clearances. A level pad or slab, airflow clearances around the fan and access for servicing.
- Timer or controls. Setting the unit to run on a controlled-load tariff overnight or during solar hours. Check whether your tariff and meter allow it.
- Noise. Placing the unit away from bedroom windows, yours and the neighbours'. Some councils and state environmental rules limit residential equipment noise at night.
Incentives that reduce the price
| Incentive | Typical form | Where to check |
|---|---|---|
| STCs (national) | Discount on the quote | Clean Energy Regulator |
| Solar Victoria hot water rebate | Rebate of 50% of the price after other discounts, up to $1,000, or up to $1,400 for eligible locally made products (as published in October 2026) | Solar Victoria |
| Victorian Energy Upgrades | Discount from accredited providers | Essential Services Commission |
| NSW Energy Savings Scheme | Discount up to $330 (gas to heat pump) or up to $640 (electric to heat pump), as published by NSW in 2026 | NSW Climate and Energy Action |
These figures are as published on the official sites when this guide was updated and they change. See the detailed guides on STCs, Victorian rebates and the NSW scheme.
Is a heat pump right for your home?
A heat pump is usually a strong option when you are replacing an electric storage tank, when you have rooftop solar and can heat water during the day, or when you plan to remove gas altogether. It needs more thought when:
- the only available location is right outside a bedroom;
- you live in an alpine or very cold area (check cold-climate ratings);
- your household uses large volumes of hot water in short bursts;
- you are in Victoria and the existing gas unit is approaching the end of its life, in which case the Victorian gas rules may decide for you.
Frequently asked questions
How long does a heat pump water heater last?
Life varies with water quality, maintenance and climate. Read the manufacturer warranty for the tank and the compressor separately, as they often differ. The Australian Consumer Law guarantees may apply beyond the warranty.
Does a heat pump work in winter?
Yes, but performance drops as the air gets colder, and recovery is slower. Units designed for cold climates and those with backup elements handle this better. Check the model's operating temperature range.
Can I install one myself?
No. Plumbing and electrical work must be done by licensed tradespeople, and incentives require compliant installation.
Do I need a new electricity tariff?
Not necessarily, but your tariff affects running costs. Compare tariffs on Energy Made Easy or your state's comparison service.
Official sources
- Clean Energy Regulator — eligible heat pump register and STCs
- Solar Victoria — hot water rebate eligibility
- NSW Climate and Energy Action — hot water upgrade incentive
- Energy Made Easy — compare electricity offers
- energy.gov.au — choosing a hot water system
