he default version A is: powered by AC220V. If your country is 110V, no 220V, you can choose Version B: DC12V It is a Konlen WIFI timing temperature controller, which can realize temperature monitoring and multi-period timing heating Or refrigeration control, high or low-temperature APP push alarm. The product is suitable for various commercial and industrial occasions,such as HVAC system, thermal water process, boiler, breeding,  intelligent electromechanical equipment and other heating/cooling control systems. Main Features: 1.Real-Time Supervision: Controller and App display real-time temperature at same time. 2.  Start/stop heating or cooling equipment remotely via App. 3.  Preset Hot or Cold working mode: can auto turn on/off equipment when it reaches to the preset temeprature value. 4. Set upper and Lower limit value of temperature alarm, real-time push alarm notification to users' smartphone. 5. Scheduled on/off, can timing-control equipments. 6. Can use button A and B to turn on/off equipment and set auto-start/stop temperature value manually, so the controller can still work via manual operation when WIFI is offline. Note:Konlen Temperature alarm notification to App is only available when network is online. A: WIFI configuration button B: Turn on/turn off button: The manual switch is only effective when the current temperature is between the preset start and stop temperature value. C:Display real time temperature D: Status LED 1, 2: Working power input: AC220V Note:  If your country is 110V, no 220V, please choose Version B: DC12V. 3, 4: Relay normal open output 5, 6: No use 7, 8: Connect with temperature sensor There is No distinction of positive and negative The manual switch of App is only effective when the current temperature is between the preset start and stop temperature value. Preset Hot or Cold working mode: When the preset start temperature is higher than stop value, it is cooling mode. For example,  xx 25 °C, start the cooling equipment; xx 10°C, stop it. When the preset start temperature is lower than stop vale, it is heating mode. For example, xx 5°C, start the heating equipment;  xx 20°C, stop it. Set upper and Lower limit value of temperature alarm For example : Set the temperature range ( 25~33 centigrade degree ) .when the temperature in house is within the temperature range , the controller will work normal .