Heat pump hot water systems are one of the fastest-growing choices for Melbourne households — and for good reason. They use significantly less energy than traditional electric systems and come with generous Victorian rebates. But are they right for your home? Here’s what you need to know.

How Does a Heat Pump Work?

A heat pump hot water system works like a reverse air conditioner. Instead of cooling air, it extracts heat from the surrounding air and uses it to heat water. Even in cold weather, there’s enough heat energy in the air for the system to work.

The process:

1. A fan draws ambient air over an evaporator containing refrigerant
2. The refrigerant absorbs heat from the air and turns into gas
3. A compressor increases the temperature of the gas
4. The hot gas passes through a heat exchanger, transferring heat to the water
5. The refrigerant cools, returns to liquid form, and the cycle repeats

Because the system moves heat rather than generating it, it uses roughly 65-75% less electricity than a traditional electric hot water system.

Pros of Heat Pump Hot Water

Dramatically Lower Running Costs

Heat pumps are the cheapest hot water system to run. They use a fraction of the electricity of a conventional electric system, and running costs are comparable to or lower than gas.

Government Rebates

Victoria offers significant rebates for installing heat pump hot water systems, making the upfront cost much more manageable. Additional Small-scale Technology Certificates (STCs) further reduce the price.

Works with Solar Panels

If you have rooftop solar, a heat pump can use your free daytime electricity to heat water — reducing running costs to near zero on sunny days.

Environmentally Friendly

Lower electricity consumption means lower greenhouse gas emissions. Switching from electric storage to a heat pump is one of the biggest carbon reductions a household can make.

Long Lifespan

Quality heat pump systems typically last 10-15 years, with some lasting even longer with proper maintenance.

No Gas Required

Heat pumps run on electricity, so there’s no need for a gas connection. This is ideal for homes without gas, or for households looking to go all-electric.

Cons to Consider

Noise

Heat pumps have an outdoor unit with a fan and compressor — similar in noise level to an air conditioning unit. They’re not silent, and placement matters. Installing too close to a bedroom window or a neighbour’s boundary can be an issue.

Upfront Cost

Heat pumps have a higher purchase and installation cost than standard electric or gas systems. However, rebates and lower running costs offset this over time.

Performance in Very Cold Weather

Heat pumps extract heat from air, so efficiency drops in very cold conditions. In Melbourne’s climate, this is rarely a major issue, but during cold snaps the system may use a backup electric element, which is less efficient.

Space Requirements

The outdoor unit needs adequate airflow and clearance. It can’t be enclosed in a cupboard or tight space.

Not Ideal for Every Home

Homes with very high hot water demand (large families, multiple bathrooms used simultaneously) need a correctly sized unit. An undersized heat pump will rely heavily on its backup element.

Is Melbourne’s Climate Suitable?

Yes. Melbourne’s climate is well-suited for heat pump hot water. While winter temperatures can drop, they rarely stay below freezing for extended periods. Modern heat pump systems are designed to work efficiently in temperatures down to -10°C, well below Melbourne’s typical lows.

The system’s efficiency does decrease in colder weather, but even accounting for Melbourne’s winter, annual running costs remain far lower than conventional electric or gas storage systems.

What About the Rebates?

Victorian government rebates make heat pumps significantly more affordable. The rebate amount and eligibility can change, so check the current offerings at the Solar Victoria website or ask us for the latest information when you get a quote.

In addition to state rebates, Small-scale Technology Certificates (STCs) provide a further discount, applied at the point of sale.

Choosing the Right Heat Pump

Key factors to consider:

• Tank size — Match the tank to your household’s daily hot water usage
• Climate rating — Choose a system rated for Melbourne’s climate zone
• Noise level — Check the dB rating and plan placement carefully
• Brand reliability — Stick with reputable brands that have good warranty terms
• COP rating — Coefficient of Performance indicates efficiency; higher is better
• Warranty — Look for at least 5 years on the compressor and tank

Hankook Plumbing Heat Pump Services

We supply and install heat pump hot water systems across Melbourne’s eastern suburbs:

• Expert advice on the right system for your home and usage
• Professional installation compliant with all Australian standards
• Rebate assistance — we help you access all available rebates
• All major brands — Reclaim, Sanden, Rheem, Rinnai, and more
• Removal and disposal of your old system

Thinking about switching to a heat pump? Call 0407 756 172 for a free consultation and quote.