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. CLS (C218)
2. CLS SEDAN GRANDE (C218)
3. R-CLASS (W251, V251)
4. C-CLASS (W204)
5. C-CLASS Saloon (W204)
6. S-CLASS (W221)
7. S-CLASS Saloon (W221)
8. E-CLASS (W212)
9. E-CLASS Saloon (W212)
10. E-CLASS T-Model (S212)
11. GLK-CLASS (X204)
12. GLK-CLASS SUV (X204)
13. C-CLASS T-Model (S204)
14. GL-CLASS (X164)
15. GL-CLASS SUV (X164)
16. M-CLASS (W166)
17. M-CLASS SUV (W166)
18. E-CLASS Coupe (C207)
19. M-CLASS (W164)
20. M-CLASS SUV (W164)
21. See more in applications

The principle of the thermostat work

The classic METZGER 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.