De Dietrich 95363348 setting thermostat 30-90C

This is a De Dietrich setting thermostat with an adjustable range of 30 to 90 °C, listed under catalogue article 336.805.011 and manufacturer code 95363348. Parts of this type are mechanical thermostats that open or close an electrical contact when the sensed temperature reaches a set point. They are used to control boiler water temperature, to limit maximum temperature, or to switch a circulation pump or burner on and off. Unlike NTC sensors, which report a continuous value to the control board, a setting thermostat acts directly on the circuit and does not require an electronic controller. When selecting a replacement thermostat of this kind, the key parameters are the temperature adjustment range (here 30–90 °C), the switching differential, the electrical rating (voltage and current), and the type of probe (for example immersion pocket or surface-mount). The mechanical design of the sensing element and the enclosure must also match the mounting arrangement in the appliance. In many boilers, such thermostats are fitted into a well in the heat exchanger or on the flow pipe. Typical failures include a drifting set point, contact welding, or loss of calibration, which can cause the boiler to overheat or fail to maintain the correct water temperature. Before installing a new thermostat, verify that the range and the probe form are compatible with the original fitting.