Thermostat, coolant - 819701 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. MEGANE III Grandtour (KZ0/1)
2. GRAN TOUR III Grandtour (KZ0/1)
3. MEGANE III Hatchback (BZ0/1_, B3_)
4. KANGOO Express (FC0/1_)
5. KANGOO Rapid (FC0/1_)
6. MODUS / GRAND MODUS (F/JP0_)
7. TWINGO II (CN0_)
8. DUSTER (HS_)
9. CUBE (Z12)
10. SCENIC III (JZ0/1_)
11. GRAND SCENIC III (JZ0/1_)
12. CLIO III Hatchback Van (SB_, SR_)
13. KANGOO BE BOP (KW0/1_)
14. LOGAN I (LS_)
15. TONDAR 90 I (LS_)
16. LOGAN I Estate (KS_)
17. TONDAR 90 I Estate (KS_)
18. NV200 / EVALIA Bus
19. EVALIA Bus
20. NV200 Bus
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.