The thermostat, serving to maintain constant temperature of the cooling water, consists of valve 1, reducing the clear opening of the water outlet connection, and bellows 2, filled with a low-boiling liquid. At a temperature below the preset value, the valve remains closed and water does not circulate through the radiator. As the temperature increases inside thermostat housing 3, the liquid in the bellows boils. The increased pressure stretches the bellows which, by means of stem 4, lifts valve 1, admitting the water into the radiator.
$4085$EHP,Rg$