Thermostatic working element

A thermostatic valve comprising:

• a valve housing having an inlet, a first outlet;
• and a second outlet;
• and
• a thermostatic working element for controlling splitting of a fluid flow, which is supplied to the inlet, between the first outlet and the second outlet, the thermostatic working element having:
• a cup-shaped housing having a housing jacket and a housing base, the housing containing a working chamber in which an expansion material is located;
• an axially adjustable working piston projecting into the working chamber through a piston opening in the housing base;
• a cover closing a housing opening lying axially opposite the housing base;
• an annular seal surrounding the working piston and lying radially thereagainst;
• and
• an axial guide in a region of the housing base and surrounding and axially guiding the working piston;
• wherein the annular seal is axially in contact on a rear end side of the annular seal facing away from the housing base with the expansion material;
• and
• wherein the annular seal lies radially against the housing jacket.