A LWCO remote monitoring and diagnosing system or device features a signal processor configured to: receive signaling containing information for running a remote low water cut off (LWCO) mobile application, and also containing information about historical data related to a LWCO circuit that monitors and controls a burner of a boiler that opens and closes to provide water to the boiler depending on the water level in the boiler; and determine corresponding signaling containing information about the historical data requested based upon the signaling received.