Solar Pump Operation

A review of the operating data from the solar collectors discovered an unexpected combination of sensor readings

The problem turned out to be that the primary circulation pump, while indicated as running by the EasyIO unit, in fact wasn't. The solar collector supply and return water temperatures were unreasonable because they were essentially room ambient temperature rather than pipes with running water to the solar collector. (Sensors are surface mounted on the piping with thermal cement and wrapped in pipe insulation.)

A check of the pump relay and found it in the "auto" position as expected. We know from this summer that the pumps ran as expected when controlled by the EasyIO unit to the "on" position. In fact the pumps were operational when manually placed in the "on" position.

A meter checked confirmed that the EasyIO unit relays, controlling each pump, we NOT closed (as expected) but had rather open contacts. It's not obvious why at this time.