Just bought a house with pool needing work (not the one in my signature). A pool contractor told me the Pentair MasterTemp 400k BTU has a maximum allowed flow rate, so I need to add a diverter valve ahead of it. This seems wildly untrue, but anyone doing something like this? Will be replacing an ancient controller with Pentair EasyTouch 8, and plan to repair and keep the old Pentair MasterTemp. Has a Pentair variable-speed pump. And switching to SWG too.