Black solar collector sensors are suited to replace the on-roof collector bulbs. These are 2 core cables which are connected back to your pump station controller. It is imperative that this part of the system is never disconnected. It controls the motion of glycol fluids around the thermal collectors. Without this small part working to 100% efficiency the whole system could stop as the sensor opens when fluid temperature rise. Then the sequence of pumping solar thermal fluids begins.
