The Multifunction digital thermostat TER-9 has several advantages such as digital thermostat with 6 functions and an inbuilt time switch clock. These thermo functions can be managed in real time for complex control of heating, water heating and solar heating in buildings. It also has two independent thermostats, 1x dependent differential themostat, 2 stage thermostat and thermostat with dead zone and heating functions. There is a program setting for output function and calibration of sensors according to the reference temperature. The thermostat has a well arranged display of set and measured data and memory for the most often used temperatures.