A monitored heat exchanger system that includes a heat exchanger unit in operable engagement with a heat generating device, with an at least one service fluid being transferable therebetween, and a monitoring module coupled to the heat exchanger unit. The monitoring module includes a primary microcontroller in operable communication with an at least one sensor assembly. The at least one sensor assembly includes a mounting frame; a support platform; a circuit board; an inner sensor housing configured to extend out and around the circuit board and the support platform; a first magnet coupled to an underside of the inner sensor housing; and a rotating member comprising a plurality of blades, the rotating member being disposed on top of the inner sensor housing.