How do I know what size fan coil I need?

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How do I know what size fan coil I need?

Calculating what size fan coil unit you need requires various design factors to be taken into consideration. These consist of building orientation, geographical location and materials used in the building’s construction; along with internal gains from sources such as lighting, equipment and occupancy.

The impact of these will then be effected by any potential plans to install solar shading, which is why the design needs to be considered as a whole to ensure any the predictions of a building’s performance are accurate.

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In most cases these calculations will be carried out by the consultant using thermal modelling systems such as Hevacomp or BIM, to be able to provide the manufacturer with the peak heating and cooling loads. These are then used to calculate what is required to meet internal design temperatures.


This detail is very important for a manufacturer as it is what they use to construct their design recommendations and will help in ensure the best all round solution is specified on a project. It also makes it easier for the manufacturer to offer a solution that is more accurately sized, to ensure optimum efficiency compared to cost and that the building’s demands will be met.

Fan coil versatility

Fan coil units are an effective and efficient design led solution for a variety of applications in both new build and refurbishment projects. They are a futureproofed and adaptable solution, providing flexibility should the space or building purpose change.


To find out more about our range of fan coil solutions or if you would like to discuss a specific project in more detail, contact our team of industry experts who will be happy to help. We also offer a range of CPDs focused on the design and specification of fan coil units, which can be presented online or in person.

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