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. C25 Bus (280_, 290_)
2. 205 II (20A/C)
3. 205 Mk II (20A/C)
4. 205 I (741A/C)
5. 205 � (741A/C)
6. 305 II (581M)
7. 305 Mk II (581M)
8. 305 II Break (581E)
9. 305 Mk II Break (581E)
10. J5 Bus (290P)
11. J5 Van (290L)
12. J5 Platform/Chassis (290L)
13. C25 Van (280_, 290_)
14. C25 Platform/Chassis (280_, 290_)
15. 205 Hatchback Van
16. J5 Van (280L)
17. 305 Estate Van (581S)
18. 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.