If a unit is too small for the room, the heat pump / air conditioner will be required to operate harder to achieve and maintain the desired temperature, which may cause extra wear and tear on its components and potentially increase running costs. As a helpful guide to finding what size unit you may need, you can use the Fujitsu Assist Tool, located on our website. However, the best way to find out what size heat pump / air conditioner you need for your room or home is to contact one of our Fujitsu Accredited Installers who are able to assess your space and determine the best unit to suit your needs. Click here to find a stockist.