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. YARIS (_P13_)
2. YARIS/VITZ (_P13_)
3. VITZ (_P13_)
4. CHARADE
5. SIRION (M3_)
6. BOON (M3_)
7. C1 (PM_, PN_)
8. 107 (PM_, PN_)
9. AYGO (_B1_)
10. YARIS (_P9_)
11. YARIS/VITZ (_P9_)
12. VITZ (_P9_)
13. CUORE VII (L275_, L285_, L276_)
14. CHARADE VII (L275_, L285_, L276_)
15. MIRA VII (L275_, L285_, L276_)
16. JUSTY IV
17. AYGO (_B4_)
18. C1 II (PA_, PS_)
19. 108
20. AYGO Hatchback Van (_B1_)
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.