What's Included in the Price
A standard quote covers old unit removal and disposal, supply and installation of the new system, plumbing connections compliant with AS/NZS 3500 Plumbing and Drainage, tempering valve (required under AS 3498), and a compliance certificate. Gas work requires a separate compliance certificate from Energy Safe Victoria. Changeover jobs (for example, gas storage to heat pump) will involve additional electrical work quoted separately.
What Affects the Cost
- System type: Gas continuous flow remains popular in Melbourne due to cold winters and compact form factor. Heat pumps are gaining ground thanks to VEU rebates and lower running costs.
- Fuel changeover: Switching from gas to electric heat pump requires an electrician for a dedicated circuit and potentially upgrading the switchboard. Gas disconnection needs a licensed gasfitter.
- Outdoor unit placement: Heat pumps need airflow and clearance. Narrow side returns on Victorian-era homes can make placement difficult.
- Rebates: VEU certificates plus federal STCs can reduce heat pump install costs significantly. Not all plumbers process VEU claims, so ask upfront.
- Weatherproofing: Exposed installations need frost protection valves in Melbourne's colder months.
A like-for-like gas continuous flow replacement in a modern townhouse with good access sits toward $1,450. A gas-to-heat-pump changeover in a Victorian-era cottage in Fitzroy with limited outdoor space, switchboard upgrade needed, and aged gas pipework to disconnect pushes toward $4,300. Most Melbourne jobs land around $2,400.
Hot water failure in Melbourne's winter months from May to September is a genuine emergency when overnight temperatures drop to 5 degrees C or lower. After-hours and weekend callouts for urgent replacements carry premium rates compared to scheduled work. If the system is still producing some hot water, booking during business hours saves money. For a complete failure in winter, most Melbourne plumbers offer same-day or next-day emergency service at a higher cost.
Melbourne-Specific Considerations
Victoria's gas ban: the biggest change in hot water. From 1 January 2027, all new homes must be all-electric. From 1 March 2027, gas hot water systems that fail in existing homes must be replaced with electric (heat pump or electric storage). Repairs to existing gas systems are still permitted, but once the system reaches end of life, it must go electric. Gas cooking and space heating in existing owner-occupied homes are not affected. For rental properties, gas hot water AND gas heaters must be replaced with electric at end of life from March 2027. This is the most significant regulatory change affecting hot water in any Australian state.
Rebates make the switch affordable. Victoria offers the most generous rebate stack in Australia. VEU (Victorian Energy Upgrades) provides up to $1,000 off. Solar Victoria hot water rebate adds up to $1,000 (or $1,400 for eligible Australian-made products from mid-2025). Federal STCs add another $700–$1,200. Combined, a heat pump that retails for ~$4,500 can cost as little as $1,500–$2,500 after all rebates. Not all plumbers are VEU-accredited, so ask upfront.
Cold climate heat pump performance. Melbourne winters can drop below 5°C overnight, but modern heat pumps are engineered for operation down to -10°C or -15°C. COP (Coefficient of Performance) drops from ~4.0 in summer to ~2.0–2.5 on cold mornings, but even at COP 2.0, a heat pump uses half the electricity of a standard element. CO2 refrigerant models (Reclaim Energy, Sanden) hold their COP better in cold weather. Cheaper models may rely on an electric booster element below 5°C.
Inner suburbs. Victorian-era homes in Fitzroy, Carlton, and Brunswick often have limited outdoor space for heat pump placement. Flexible gas connectors older than five years must be replaced under Energy Safe Victoria requirements during any gas-related work. Melbourne's soft water means less mineral buildup and longer tank life than Perth or Adelaide.
For water supply emergencies, contact Yarra Valley Water (13 27 62), South East Water (132 812), or Greater Western Water (13 44 99).
Hiring a Licensed Plumber in VIC
All hot water work in Victoria must be done by a plumber registered through the Victorian Building Authority. Gas-related work requires a gasfitter endorsement, and the plumber must issue an ESV compliance certificate for any gas installation or disconnection. Ask whether they handle VEU rebate paperwork. Some plumbers partner with certificate providers and apply the discount at point of sale.
How We Calculate
Estimates are based on current trade rates for licensed plumbers in VIC, adjusted for Melbourne labour costs and typical material prices. All figures include GST. Ranges cover straightforward replacements through to system changeovers.