Item Type: Thermostat Model: 8819H Material: PC + ABS Gross Weight: Approx. 181g / 6.4oz Control Type: Temperature Control Mode: Intelligent Temperature Control Regulator Measurement Object: Environment, Object Input Voltage: AC220V Temperature Range: 5-45 () Load Output Power: Plumbing 220V AC/3A Electric Heater 220V AC/25A Temperature Measurement Error: 1 () Hole Size: Approx. 60mm / 2.4in Installation Type: Concealed Output Signal: 250000 (mA) Working Voltage: 220 (V) 1Applicable Scenarios: Temperature control of central air conditioning system, water heating system, electric heating system. 2Functions: Temperature detection, temperature compensation, user settings, fan settings, overheat protection, antifreeze, etc. 3Household Thermostat: Built in high accuracy NTC temperature sensor, intelligent temperature control and adjustment. 4High Quality: Made of premium PC and ABS material, sturdy and durable in use. 5Working Principle: By comparing the data set by the user, the corresponding control signal is output in the setting mode to control the electric valve or fan.Thermostat installation 1. Disassemble the main control board and use a 3.5mm wide flat?head screwdriver to extend it to the slot along the slope 2. Remove the 4mm of the cable and pry up slightly to open the card slot 3. Use a screwdriver to tighten after connecting the terminals according to the wiring diagram 4. Install the connected thermostat on the press box to use 1 x Thermostat 2 x Screw