Skip to content
We've helped thousands of households get free energy upgrades in the last 7 years
Warma UK logo
Heat Pump Demand

What Size Air Source Heat Pump Do I Need for My Home?

While you might have read or heard that heat pumps are not suitable for homes in the UK, that is not true. They work exceptionally well in the UK and have been proven to deliver, even when they operate at temperatures of as low as -20 degrees. Despite this, it makes sense to ensure that your heat pump operates efficiently while keeping your home warm. To achieve this, you will need to make sure that your heat pump is the right size for your home.

However, it is important to recognise that sizing up your heat pump is not something that you can do yourself. Therefore, you will need an experienced and certified heat pump installer who will be able to determine the exact design that will work for your property. With all of this in mind, we aim to give you an idea of what sort of sized heat pump you require, so take a look at our brief guide that will help you to understand how heat pumps are sized.

The Difference Sized Heat Pumps Available

Heat pumps can be found in a variety of sizes which means that they can range from 6kW and up to 15kW with those that have a higher rating producing more heat for your home. A heat pump that has been correctly sized for your property will be able to heat your home correctly all year round although that doesn’t mean that the bigger the system is, the better it will perform. If your system is too big, then it will short cycle and that will mean that it will shut off too soon before coming back on for another short cycle. This is not an efficient way to run this kind of system.

What Determines the Size of Your Heat Pump

There are three main factors that will determine the size of your heat pump and they are:

  • The Type of Home You Own

It is fairly obvious when we say that bigger homes are going to need bigger heat pumps although there are certain factors that can have an impact on what will work for you. This includes things such as whether you live in a bungalow or a townhouse, how suitable your insulation is and the size of every room, all of which can have an impact on the effectiveness of your heat pump. An Energy Performance Certificate will help you to understand what structural factors will influence the size of your heat pump and you will need one of these if you are going to take advantage of the Renewable Heat Incentive.

  • Your Location

The temperature from one part of the country to another can differ and this is something that will need to be considered when it comes to designing your heat pump system. Your installer should consider the coldest air temperatures of the year for your location and then design the system around that. The Microgeneration Certification  Scheme (MCS) will provide this information and so, the warmer your location is, the smaller the heat pump can be.

  • The Heating System You Are Using

The heat distribution system that you plan to use will also have an influence on the size of your heat pump. As an example, underfloor heating can operate at a lower temperature, whereas radiators will need to operate at higher temperatures and have bigger surface areas in order to ensure that they deliver a comfortable heat that is easy to maintain. Having radiators that are the correct size as well as the correct temperature for each specific room will help to identify the right-sized heat pump. 

To ensure that you are receiving the right sized heat pump for your property, you should ensure that the installer you use is MCS certified. This is also an essential criteria for eligibility for the RHI. You should opt to use installers who are members of the Home Insulation and Energy System Contractors Scheme or the Renewable Energy Consumer Code, as this will ensure that you benefit from a higher level of customer care.

Despite our guide, you should make sure that you use a professional to size up your heat pump as this will ensure that you get a solid return on your investment. It will also mean that your system operates as intended and you benefit from the right heat and the right price.

Worcester Bosch Boiler

Homeowners are still able to get a FREE boiler grant or insulation grant via the ECO scheme, which is still available to households that qualify. Warma UK are currently working throughout the UK helping privately owned and rented homes to improve home energy efficiency and save money on rising energy bills.

For more information email –

Or call 03304600065

Apply For Your Government Backed Heating Grant

Following your successful application, we will arrange a free, no obligation survey to ensure the maximum grant is obtained and advise you on the best products to reduce your homes energy usage.

Michael Cornish

Michael Cornish