Boiler stove sizing

Correctly sizing your boiler stove is a calculation that should be left to an experienced heating engineer. The approximate heat consumptions of various heating components are listed here as a very rough guide to let you shorten the list of boiler stoves which might be suitable for your needs.
Approximate heat consumptions
120lt domestic hot water tank2.6kW (9,000 BTU)
600mm x 1200mm double radiator2kW (7,030 BTU)
600mm x 1000mm double radiator 1.7kW (5,850 BTU)
600mm x 800mm double radiator 1.4kW (4,680 BTU)
600mm x 600mm double radiator 1kW (3,510 BTU)

We use the 600mm x 1000mm double radiator rated at 1.7kW, and a 120lt hot water tank rated at 2.6kW as the indicators of stove boiler output on this site.

Of course the actual output needed depends on the size and number of your radiators, the level of insulation in your house, the size of your hot water tank and your level of hot water usage. So please use this rule to give yourself a rough idea of the type of boiler output that you are likely to need, but then consult with a heating engineer to make your final decision.

You can use our boiler stove wizard to select stoves that might meet your needs. Simply select whether you would like to run a 120lt hot water tank and enter in how many radiators of various sizes you would like to power and the wizard will show you stoves with matching boiler outputs.