Hello all,

I have recently added a further 3 radiators and an additional 14m
approximately of pipework to incorporate an extension.

I have been to a site where it indicates the flow required and the BTU that
the pipe size can manage etc but there was no indication of the pump
requirements. Apart from a "suck it and see" scenario is there anyway of
calculating the pump specifications? How do builders determine the correct
size pump for a new installation?

Mark