Heat pump sizing made simple

Intro

Modernising your home

Why switching to a heat pump is a good idea.

Are you thinking about making the switch to a heat pump? Good Choice! Heat pumps are a sustainable, energy efficient solution that provides both heating and hot water. They are designed for long-lasting performance with minimal maintenance.

Learn more about modernising with a heat pump

What heat pump sizes are available?

When selecting a heat pump, the size actually refers to its heating capacity measured in kilowatts (kW) – not its physical dimensions. This capacity determines how effectively your heat pump can warm your home and provide hot water throughout the year.

Choosing the right capacity is essential for both comfort and efficiency. A properly sized system ensures optimal performance while keeping your energy consumption and operating costs as low as possible.

Calculation of heat pumps size

Heat pump math: find the ideal size for maximum comfort.

The correct size of the heat pump is crucial for efficient and long-lasting operation. For an initial assessment, we have written a detailed guide to help you calculate the required capacity in kW for your home. However, this can by no means replace an experienced expert.

The best choice: let an experts do the math.

Whether you're good at maths or not – choosing the right heat pump size is new territory for all homeowners. That's why you should rely on an expert: Your local partner can perform a detailed heat loss calculation and recommend the best heat pump size for your home.

Find a local partner Learn more about heat pumps

Find your perfect fit

Let's have a look at our heat pump sizes and dimensions.

Modern heat pumps are surprisingly compact. Our air source heat pumps require about as much space as two standard wheelie bins, making them easy to accommodate even in homes with limited outdoor space. You'll simply need to ensure there's enough space around the unit for proper airflow and maintenance access. Below is a breakdown of our heat pumps:

	Height (mm)	Width (mm)	Depth (mm)
aroTHERM plus 3.5kW	765	1,100	490
aroTHERM plus 5kW	765
aroTHERM plus 7kW	965
aroTHERM plus 10W	1,565
aroTHERM plus 12kW	1,565
aroTHERM split 3.5kW	765
aroTHERM split 5kW	765
aroTHERM split 7kW	965
aroTHERM split 10kW	1,565
aroTHERM split 12kW	1,565
aroTHERM 5kW	840	980	408
aroTHERM 8kW	975	1,103	463
aroTHERM 11kW	975
aroTHERM 15kW	1,380
flexoTHERM 5kW	1,256	1,192	785
flexoTHERM 8kW
flexoTHERM 11kW
flexoTHERM 15kW
flexoTHERM 19kW

You should plan this space for your heat pump.

Air source heat pumps are usually installed on the exterior of properties. When installing a heat pump outside your property have a look at the following aspects:

Flat solid surface.
The surface is important to properly mount your heat pump.
Space for the heat pump and refrigerant.
Look for the width and height of your model and the space clearance the refrigerant.
Learn more about the natural refrigerant R290
Clear space for air flow.
At least 1.5 metres in front of the heat pump fans as this avoids recirculation of cold air.
Room for pipes.
They deliver the heat into your home and need to be close. Their size may vary.

Even less safety clearance: with our flexible space function.

Our innovative flexible space function dramatically reduces the protective zone required around your heat pump, giving you unprecedented installation flexibility. This means you can position your system in locations that were previously off-limits – even near doors, windows or cellar shafts.

Learn more about our flexible space function

Frequently asked questions

Still have questions? We have the answers.

How does an incorrectly sized heat pump affect performance?

What are the benefits of correctly sizing a heat pump?

Can a professional help with heat pump sizing?

Dive deeper into efficient heating.

Man reading book in garden in front of a heat pump

Heat pump sizing made easy: a guide to finding the perfect heat pump for your home.