---
title: Hydronic Heat Pumps Melbourne
date: 2023-05-07T20:28:00+10:00
author: Darren Burch
canonical_url: "https://sogeo.com.au/air-source-heat-pumps"
section: Pages
---
![Stiebel Eltron R290 Hydronic Heat Pump]()

#  Hydronic Heat Pumps Melbourne 

SóGeo supplies, installs and commissions **hydronic heat pumps** across **Melbourne**. One electric air-to-water heat pump heats the water in your radiators, underfloor pipework or fan coils, cools the home in summer and can supply hot water. We install the Stiebel Eltron WPL range and design every system from a room-by-room heat-loss calculation, so it runs at a SCOP of 5 or higher.

 

 

 

 **The short answer.** Heat pump hydronic heating replaces a gas boiler with an electric air-to-water heat pump that heats the water in your radiators, underfloor pipes or fan coils. In Melbourne, a SóGeo swap from gas boiler to hydronic heat pump starts at $15,000 when the existing radiators and pipework stay. Most installs run higher with home size, hot water integration and any radiator upgrades the heat-loss calculation identifies. A well-designed system typically returns a SCOP of 5 or higher, so a typical Melbourne home running it 10 hours a day through a five-month winter spends about $900 to $1,350 a year on electricity, against about $4,100 on gas. Every job gets a fixed quote after a site visit and heat-loss calculation. The full price breakdown is in our [hydronic heating cost guide](/blog/how-much-does-it-cost-to-switch-from-gas-to-hydronic-heat-pumps).

## What is a hydronic heat pump?

A hydronic heat pump is an air source heat pump that heats water instead of air, which is why it is also called an air-to-water heat pump. The outdoor unit draws heat from the outside air and transfers it into a sealed water loop. That water circulates through radiators, underfloor pipework or fan coils to heat the home. In summer the cycle reverses and the same pipework cools the home. One system covers both seasons, with no separate air conditioner needed.

Because it moves heat rather than burning fuel to make it, a well-designed unit delivers roughly 4 to 5 units of heat for every unit of electricity it uses. A gas boiler tops out near 90% efficiency.

For a plain-English walk through of sizing, running costs and the design mistakes that leave a home cold, read our [guide to heat pump hydronic heating in Melbourne](/blog/heat-pump-hydronic-heating-melbourne-guide).

## Air-to-water, not air-to-air

**Air-to-water** heat pumps heat water that circulates through radiators, underfloor heating or a hot water cylinder. This is what SóGeo installs. Water-based distribution gives even, quiet heating with no air movement and no dust being blown around.

**Air-to-air** heat pumps push warmed or cooled air into rooms through wall-mounted indoor units. Most people in Australia call this a split system. It works, but it is noisier, the comfort is less even, and it cannot supply hot water.

## How a hydronic heat pump works

The cycle has four steps:

1. A fan draws outdoor air across a coil filled with R290 refrigerant. Even in cold weather, the refrigerant absorbs heat from the air.
2. The refrigerant is compressed, which raises its temperature.
3. The hot refrigerant passes through a heat exchanger, transferring its energy into the building’s water loop.
4. In summer the cycle reverses, pulling heat out of the home and rejecting it outside.

## The hydronic heat pumps we install: Stiebel Eltron WPL-A Trend

The WPL-A Trend is the hydronic heat pump SóGeo installs on most Melbourne homes. It handles heating, hot water and summer cooling from a single outdoor unit, and runs on R290, a natural refrigerant with very low environmental impact. Three models cover most homes:

- **WPL-A Trend 10.2:** 2.76 to 10.97 kW output (single phase), COP 5.40, 48 dB(A) sound power
- **WPL-A Trend 13.2:** 3.69 to 13.92 kW output (three phase), COP 5.36, 49 dB(A) sound power
- **WPL-A Trend 17.2:** 5.11 to 19.64 kW output (three phase), COP 5.29, 49 dB(A) sound power

(Output range from minimum to maximum, and COP, rated at A7/W35, the standard 7°C air, 35°C flow test condition.)

What sets this range apart:

- A+++ energy efficiency class across all three models
- Inverter technology that matches output to the load rather than cycling on and off
- Flow temperatures up to 75°C, high enough to drive existing radiators in a retrofit, which most heat pumps cannot manage
- Smart Grid ready for connection to solar PV and home energy management
- Made in Germany

For the ground source option, SóGeo installs the Stiebel Eltron WPE geothermal range, and we are the exclusive Victorian distributor and installer of it. Ground source holds a COP of 5 to 7 year-round because ground temperatures stay stable, and the buried pipework lasts 50+ years. See our [ground source heat pumps](/ground-source-heat-pumps) page for the full picture.

## Performance in the Melbourne climate

Performance comes down to how the system is designed and commissioned, not just the equipment. A SóGeo install typically delivers a SCOP (Seasonal Coefficient of Performance) of 5 or higher across the year, and never less than 4 even on a demanding retrofit, because our heat-loss calculation upsizes radiators where needed to keep flow temperatures down. The industry average sits at SCOP 3.0 to 3.5, which we treat as a poor result. The difference is design discipline: correct sizing against the heat-loss calculation, weather-compensation tuning and proper hydraulic balancing.

Cooling performance does drop in a heatwave. On a 35°C day the cooling COP can fall to 2.5, and on a 40°C+ day it can drop below 2. For homes that want consistent year-round performance whatever the weather, a ground source heat pump holds COP 5 to 7.

## Replacing a gas boiler with a hydronic heat pump

Most existing hydronic systems (radiators, in-slab underfloor or fan coils) can run on a hydronic heat pump in place of a gas boiler. The water side of the system stays. SóGeo disconnects and removes the boiler, installs the heat pump, modifies pipework where needed and recommissions the system on electricity. Existing radiators stay if they are correctly sized for the heat pump’s flow temperature, which we check during the heat-loss calculation. If any need upsizing, that goes into the quote upfront. If your boiler is failing now, see [replacing your gas boiler with a hydronic heat pump](/replace-gas-boiler-hydronic-heat-pump).

## What it costs to supply and install

A straightforward gas boiler to hydronic heat pump swap that keeps your existing radiators starts at $15,000. Most projects run higher with home size, scope, hot water integration and any emitter or insulation upgrades the heat-loss calculation identifies. Larger or new-build systems are quoted from drawings. The full breakdown is in our [cost guide](/blog/how-much-does-it-cost-to-switch-from-gas-to-hydronic-heat-pumps).

## One team owns the whole job

With SóGeo, the same team designs, supplies, installs and commissions your system. We run the heat-loss calculation, size the system to your building, supply the Stiebel Eltron unit, install it, and commission it to hit its SCOP target.

This matters more than it sounds. A hydronic heat pump only performs as well as the design behind it. Most underperforming systems trace back to a unit sold by one business and installed by another, with nobody owning the result. SóGeo owns it from the first site visit to the last commissioning check.

That work is led by Director Darren Burch, who has been installing hydronics for over twenty years, fourteen of those in Australia, drawing on three generations of the trade from Ireland to Melbourne. It is the same approach behind our [hydronic heating systems across Melbourne](/hydronic-heating-cooling).

Every SóGeo project runs the same way:

1. Site visit and room-by-room heat-loss calculation
2. A fixed quote against the design, with no estimates and no surprises
3. Supply, install and commission
4. A system that runs the way it was designed for the next twenty years

 

 

   ![Stiebel Eltron Heat Pump]() 

  

 ###  Designed around your building 

Unlike conventional split systems or ducted air conditioning, hydronic heat pumps provide a gentler and more consistent climate experience, with reduced airflow, less dust, and better compatibility with energy-efficient, air-tight buildings.  
  
At SóGeo, no two systems are alike. Every installation is designed from the ground up to suit the building’s architecture, insulation, orientation, occupancy, and climate zone. We take the time to understand how the home or building will be used and design your heating and cooling system accordingly.

Whether it’s a **passive house** with low energy demand needing **heat recovery ventilation** or a large home requiring zone control, we engineer systems that balance comfort, efficiency, and aesthetics. Clean installations, intelligent layout planning, and the use of premium componentry are standard on every SóGeo project.

[**Contact Us For a Free Quote** ](https://sogeo.com.au/contact-us)

 - Reduced environmental impact
- Long lifespan
- Lower energy bills
- Comfortable living
 
 

  01 

 ![Casey horner 4r D Ca5h Bl Cs unsplash]() 

 

### Maximum benefits. Minimum environmental impact.

Besides being kinder to the environment, **hydronic heat pumps** are highly beneficial in many ways.

- High energy efficiency, even in cold winters.
- Heat pump unit is located outside the property, with little space required.
- Can be paired with solar PV, unlike gas boilers.
- Lower running costs than gas boilers, reducing the cost of energy bills.

 

 

 

  ## Frequently asked questions

  ### What is a hydronic heat pump?

 ➕ An air-to-water heat pump that transfers heat from outside air into a sealed water loop. The water circulates through underfloor pipework, panel radiators or fan coils. SóGeo installs the inverter-driven Stiebel Eltron WPL-A Trend range.

   ### What is the difference between a hydronic heat pump and a gas boiler?

 ➕ A boiler burns gas to make heat and tops out near 90% efficiency. A hydronic heat pump moves heat instead of making it, delivering roughly 4 to 5 units of heat per unit of electricity. It also runs on electricity, so it can pair with solar PV.

   ### How is a hydronic heat pump different from ducted reverse-cycle?

 ➕ Ducted systems blow heated or cooled air through ductwork. Hydronic systems circulate temperature-controlled water through underfloor pipework, radiators or fan coils. The result is silent indoor operation, even temperature across the room, solar PV integration and a longer system life. Ducted installs faster and costs less upfront; hydronic delivers better comfort and lower running costs over the life of the system.

   ### Can a hydronic heat pump run my existing radiators?

 ➕ Often yes. The Stiebel WPL-A Trend reaches flow temperatures of 75°C, high enough to drive existing radiators that older, lower-temperature heat pumps could not. We confirm it against your radiators during the heat-loss calculation.

   ### How efficient is a hydronic heat pump?

 ➕ A SóGeo install typically delivers a SCOP of 5 or higher across the year, the seasonal average that shows on your bill. The WPL-A Trend reaches a COP of 5.40 at the standard test point and is A+++ rated. The industry average install sits at 3.0 to 3.5, which we treat as a poor result.

   ### Will a hydronic heat pump increase my electricity bill?

 ➕ Your electricity bill goes up, but your gas bill goes away, and the total drops sharply. A typical Melbourne home running the system 10 hours a day across a five-month winter spends around $900 to $1,350 a year on electricity, against around $4,100 a year on gas. Pair it with rooftop solar PV and the daytime running cost can drop close to zero.

   ### Are hydronic heat pumps noisy?

 ➕ No. The outdoor unit has a sound power level of 48 to 49 dB(A) depending on the model, and because heat is delivered through water rather than forced air, the house itself stays silent.

   ### What are the disadvantages of a hydronic heat pump?

 ➕ Four worth knowing. (1) It costs more upfront than ducted reverse-cycle: a straightforward boiler swap keeping your radiators starts at $15,000, and new-build systems are quoted from drawings. (2) It is designed to run steadily at low load rather than being switched on and off, which is how it holds an even temperature efficiently. (3) Running cost depends on the building, so a well-insulated home does best; we factor the envelope into every design. (4) Standard panel radiators heat only. Where cooling is required, we specify hydronic underfloor or fan coils driven by the same heat pump.

   ### Do you supply the heat pump or just install it?

 ➕ Both. SóGeo supplies the Stiebel Eltron unit and installs it as one job, so there is one point of accountability for the whole system.

   ### How much does a hydronic heat pump cost to supply and install?

 ➕ A straightforward boiler-to-heat-pump swap keeping existing radiators starts at $15,000. Most installs run higher with home size, scope and hot water integration. Larger or new-build systems are quoted from drawings after a site visit. See our [cost guide](/blog/how-much-does-it-cost-to-switch-from-gas-to-hydronic-heat-pumps).

  

 

  

  ![Jan huber 4 Oh FZSAT3sw unsplash]() ## The SóGeo Difference

Our team of experts are European trained and utilise the most sophisticated technologies for their installations. Whether you’re a homeowner or a business operator, we're here to help you make the transition to a more innovative and effective system.

 

 

 

 ## Contact Us

Get a free quote for your hydronic heat pump at SóGeo.

 

 

 

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