3KW Electric Water Heater Thermostat for Swimming Pool, Bathtub, SPA & Hot Tub — Quiet Operation

Built-in ultra-high temperature protection switch prevents overheating and protects users. After installation, perform an initial safety verification: fill the tub to the correct level and start the system so it can run its automatic self-check. Let the unit operate until the thermostat stabilizes at its highest setting and the display lights go out, then confirm the water temperature with an accurate thermometer — it should read 40 °C. Operation details: - Fully automatic thermostat control. Turn the control clockwise to switch heating on; the indicator light will illuminate. When the preset temperature is reached the heater will hold that temperature. - The device will maintain temperature within a range not exceeding 40 °C (104 °F). If the unit is started with cold water, expect the temperature to rise at approximately 6 ~ 8 °C / h. - Automatic cycling: the thermostat heats to the preset temperature, then stops until the temperature falls a few degrees, at which point it automatically restarts. - Ultra-high temperature safety: if the water exceeds 49 °C, the ultra-high temperature switch will trip and cut power (power off).