Isomac Boiler Thermal Fuse - I5363014 control-board The expansion valve (also called

The expansion valve (also called an OPV — over-pressure valve) regulates pump pressure during espresso extraction

and machine longevity

causing steam leaks

When Do You Need This Part

Isomac Boiler Thermal Fuse - I5363014 control-board The expansion valve (also calledIsomac Boiler Thermal Fuse Safety Replacement The thermal fuse (also called a thermal cutout or high limit switch) is a one time safety device mounted on the boiler of your Isomac espresso machine. If the boiler overheats beyond a safe threshold due to a failed pressurestat, low water, or other fault the thermal fuse blows permanently, cutting power to the heating element to prevent damage or fire. Once blown, it must be replaced; it cannot be reset.