ACV Mechanical thermostat with manual reset 54764037

The ACV 54764037 is a mechanical safety thermostat with manual reset, designed for a switching temperature of 96 °C and a 2-pole contact configuration. It functions as a temperature limit switch, opening the circuit when the sensed temperature reaches 96 °C to interrupt the safety chain and stop the burner. The manual reset requires a service technician to press the reset button after the fault is resolved. This thermostat is compatible with ACV Prestige 75 MK2 and Prestige 100 MK2 boilers, and it replaces the older model 54764010.

When selecting a replacement thermostat of this kind, verify the switching temperature, reset type (manual or automatic), number of poles, and mechanical fixing method (probe form, immersion depth, or mounting bracket). Ensure the electrical rating matches the burner control circuit. Confirm the type designation (e.g., 'type tod') matches the original to ensure correct internal mechanism and reset travel.

Typical failures in mechanical thermostats of this kind include drift of the switching point due to ageing, broken capillary tubes, or poor thermal contact between the sensor and the pipe. When a failure occurs, the burner may not start or may shut down unexpectedly, and the safety chain may remain open even after the temperature drops, requiring manual reset.