3KW Electric Water Heater Thermostat for Swimming Pool, Bathtub, SPA & Massage Hot Tub - Efficient Heating

Safety and initial setup: This thermostat features an ultra-high temperature protection switch to prevent overheating and protect users. After installation is finished, perform a safety check before first use. Fill the tub to an appropriate water level and start the system; the thermostat will run an automatic self-check and continue operating until the temperature stabilizes at the highest setting and the display lights go out. Verify with a precise thermometer—the water temperature should read 40 °C. Automatic operation: The thermostat is fully automatic. Turn the control clockwise to switch heating on; an indicator light shows when heating is active. Once the preset temperature is reached, the unit will hold that temperature. Temperature control and performance: The device is designed to maintain water at a temperature not exceeding 40 °C (104 °F). If cold water is introduced, the temperature will rise at a rate of 6 ~ 8 °C / h. The thermostat cycles automatically: it heats until the preset is reached, then stops, and will restart when the temperature falls by a few degrees. Over-temperature protection: If the water temperature exceeds 49 °C, the ultra-high temperature switch will trip and cut power to the unit to ensure safety.