Thermostat, coolant - 820565 VALEO

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. C-MAX II (DXA/CB7, DXA/CEU)
2. GRAND C-MAX (DXA/CB7, DXA/CEU)
3. FIESTA IV (JA_, JB_)
4. FIESTA Mk IV (JA_, JB_)
5. 121 III (JASM, JBSM)
6. SOHO III (JASM, JBSM)
7. FIESTA Van (J5_, J3_)
8. COURIER Van (J5_, J3_)
9. MONDEO IV (BA7)
10. MONDEO IV Turnier (BA7)
11. PUMA (EC_)
12. FOCUS III Saloon
13. FOCUS III
14. FOCUS III Turnier
15. KADETT E Hatchback (T85)
16. KADETT E (T85)
17. MONZA E (T85)
18. KADETT E Estate (T85)
19. FOCUS (DAW, DBW)
20. FOCUS Saloon (DFW)
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.