1. How can I tell if my flow center's pump(s) are running?
Measure the fluid pressure drop across the heat pump’s heat exchanger. If there is a pressure difference/drop between the “water in” and “water out” connections, fluid is flowing. This is accomplished with a pressure gauge equipped with a needle pushed into the PT ports on the heat pump elbows. To determine the flow rate, look up the pressure drop tables in the heat pump manufacturer’s literature.