External Contact Control module to control an indoor unit (ON/OFF) via 0V dry contact. MIM-B14 also provides an operation and error out put (0V dry contact) signal. MIM-B14 is also used for various other indoor unit operation depending on indoor unit series and model (EX: DVM S supplemental heat control and unoccupied room control). MIM-B14 can also install in DVM S outdoor units to monitor system ON/OFF status, error status, and to manually enable night time quiet operation mode.