I need to build up Professional Development Hours to keep my engineering license active. In the past I have taken various courses including Siegenthaler's Radiant Heat Systems Design the last time around. It was an in depth course but not inexpensive. For this license cycle I have been viewing recorded webinars on the Grundfos training site. There are a lot of great (and some not so great) 1 hour webinars that are free for the watching https://go.bluevolt.com/Grundfos/Catalog/Recorded-Webinar/17398/ They generally dont go into intensive detail but are good for initial awareness level. An example of good one is how to size a submersible pump https://go.bluevolt.com/Grundfos/CourseOutline/How-to-Select-a-Submersible-Well-Pump/89389?EnrollmentID=7522072 It covers all the terms and basic equipment and how to size a pump plus covers some basic concepts that a lot of folks dont think about. They have several courses on radiant heating an various pumping systems. I did find the solar pumping series marginal as it was oriented to third world applications.