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. 123 Saloon (W123)
4. 123 T-Model (S123)
5. 123 Break (S123)
6. 124 Saloon (W124)
7. E-CLASS (W124)
8. E-CLASS Saloon (W124)
9. 124 T-Model (S124)
10. 124 Break (S124)
11. E-CLASS T-Model (S124)
12. E-CLASS Break (S124)
13. S-CLASS (W126)
14. S-CLASS Saloon (W126)
15. 123 Coupe (C123)
16. 124 Coupe (C124)
17. 124 Convertible (A124)
18. E-CLASS Coupe (C124)
19. SL (R129)
20. S-CLASS (W140)
21. See more in applications

The principle of the thermostat work

The classic TOPRAN 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.