The pump is not a one size fits all. Each designer should take into account the Disposable/Available Pump Head curve found on page 4 of the NextGen Boiler installation manual. Failure to comply with this curve may result in problems with heating the application properly. Depending on how the system is designed, the primary pump can handle most applications where a 20 Delta T is used. Note that the 14.4 kW model likely will require a secondary pump when installed with hydraulic separator or closely spaced tees.