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. 100 / METRO Hatchback (XP)
2. 100 Convertible (XP)
3. PASSAT Variant (3C5)
4. PASSAT Estate (3C5)
5. 200 Hatchback (XW)
6. TIGUAN (5N_)
7. TIGUAN/TIGUAN LIMITED SUV (5N_)
8. PASSAT CC (357)
9. CC (357)
10. PASSAT CC SEDAN GRANDE (357)
11. A3 (8P1)
12. A3 / S3 (8P1)
13. TOURAN (1T1, 1T2)
14. GOLF V (1K1)
15. RABBIT V (1K1)
16. A6 (4F2, C6)
17. A6 Saloon (4F2, C6)
18. A6 / S6 (4F2, C6)
19. ALTEA (5P1)
20. OCTAVIA II (1Z3)
21. See more in applications

The principle of the thermostat work

The classic CALORSTAT by Vernet 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.