Thermostat, coolant - 819709 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. LAGUNA I (B56_, 556_)
2. LAGUNA I Grandtour (K56_)
3. LAGUNA I Nevada (K56_)
4. LAGUNA I Estate (K56_)
5. ESPACE III (JE0_)
6. ESPACE Mk III (JE0_)
7. SAFRANE II (B54_)
8. SAFRANE Mk II (B54_)
9. LAGUNA II (BG0/1_)
10. LAGUNA II Grandtour (KG0/1_)
11. LAGUNA II Sport Tourer (KG0/1_)
12. CLIO II (BB_, CB_)
13. CLIO Mk II (BB_, CB_)
14. LUTECIA II (BB_, CB_)
15. CLIO MIO II (BB_, CB_)
16. AVANTIME (DE0_)
17. PHEDRA (179_)
18. ULYSSE (179_)
19. ESPACE IV (JK0/1_)
20. ESPACE Mk IV (JK0/1_)
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.