Thermostat is a device for maintaining a static (constant) temperature, as its name implies. There are thermostats of different designs in many devices and mechanisms, from water heaters to refrigerators. There is also a thermostat in a car's internal combustion engine (liquid-cooled, of course). In a car, the thermostat regulates the temperature of the coolant (antifreeze): it accelerates the warm-up of a cold engine and provides heat removal from the hot one. Therefore, the engine works more efficiently and more comfortably for the driver, especially in winter - without a thermostat, the stove would usually blew cold air.

1. 190 (W201)
2. 190 Saloon (W201)
3. 124 Saloon (W124)
4. 124 T-Model (S124)
5. 124 Break (S124)
6. G-CLASS (W463)
7. G-CLASS SUV (W463)
8. S-CLASS (W140)
9. S-CLASS Saloon (W140)
10. E-CLASS (W124)
11. E-CLASS Saloon (W124)
12. E-CLASS T-Model (S124)
13. E-CLASS Break (S124)
14. C-CLASS (W202)
15. C-CLASS Saloon (W202)
16. VITO Bus (638)
17. C-CLASS T-Model (S202)
18. C-CLASS Break (S202)
19. G-CLASS Cabrio (W463)
20. V-CLASS (638/2)
21. See more in applications

The principle of the thermostat work

The classic VALEO brand Thermostat, coolant is a movable valve that moves due to a change in the external environment - heating or cooling of antifreeze. The thermostat is made of a thermoelement filled with a substance resembling wax in structure - ceresin, with the addition of copper powder, graphite or aluminum for better thermal conductivity. At a certain temperature of the antifreeze, ceresin expands, opening the thermostat valve. When the motor cools down, ceresin contracts and the thermostat closes again.