Method and apparatus using phases for communication in thermostat circuit

摘要: In a receiver circuit module ( 22 ) having microcontroller (U 1 ), an output line (FILTER_LED) connectable to source 20 is also used as input. A switch (SW 2 disposed in the closed change wave form which read by input signal drive 5V gate of solid state (Q turning it on thereby energize device via same (FILTER_LED). By means dual function control can notify user HVAC system, for example, system problems with blinking light and/or audible alarm well serving at remote location that selected maintenance due, such need filters without additional lines. The be mounted near thermostat or central heating and cooling unit.