A heating system isolated from the atmosphere has a certain capacity. The internal hydraulic pressure in a closed system filled with water rises with increasing temperature and the tendency of water to expand and can exceed the tensile strength of its individual elements. Therefore, a damper is introduced into the water heating system - an expansion tank.

1. POLO (6N1)
2. POLO CLASSIC (6V2)
3. FLIGHT CLASSIC (6V2)
4. DERBY CLASSIC (6V2)
5. CADDY II Box Body/MPV (9K9A)
6. VAN II Box Body/MPV (9K9A)
7. PANEL II Box Body/MPV (9K9A)
8. CADDY Mk II (9K9A)
9. AROSA (6H)
10. LUPO (6X1, 6E1)
11. POLO Variant (6V5)
12. POLO Estate (6V5)
13. CADDY II Pickup (9U7)
14. CADDY Mk II (9U7)
15. POLO Hatchback Van (86CF)
16. POLO Van Hatchback Van (6N1)
17. POLO (6N2)
18. CADDY II MPV (9K9B)
19. CADDY II VAN (9K9B)
20. CADDY II Estate (9K9B)
21. See more in applications

The functionality of the expansion tank coolant

The main purpose of the expansion tank is to receive an increase in the volume of water in the system, which is formed when it is heated, in order to maintain a certain hydrostatic pressure. In addition, the tank is designed to replenish the loss of water volume in the system with a slight leak and with a decrease in its temperature. Through an open tank, excess water is removed into the drain when the system is overfilled. The second important purpose of the expansion tank is to collect the air released from the water when it is heated in a heat generator.