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. 307 (3A/C)
2. 407 (6D_)
3. 407 Saloon (6D_)
4. 307 Break (3E)
5. 307 Estate (3E)
6. 307 SW (3H)
7. 407 SW (6E_)
8. C4 I (LC_)
9. C4 Coupe (LA_)
10. C5 II (RC_)
11. C5 II Break (RE_)
12. 307 CC (3B)
13. C4 PICASSO I MPV (UD_)
14. C4 GRAND PICASSO I (UA_)
15. 407 Coupe (6C_)
16. 307 SW Estate Van (3E_, 3H_)
17. C5 Estate Van (DE_, RE_)
18. 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.