O-Ring-21x1.50, De Dietrich 7630737

The O-ring with dimensions 21x1.50 mm is a small but crucial sealing element used in many boiler and burner components. It prevents leaks by creating a tight seal between mating parts, such as in valves, pumps, or connectors. This O-ring is made from a flexible material that resists heat and chemicals commonly found in heating systems. When replacing worn seals, using the correct size ensures proper function and avoids system failures. It is a common spare part for heating equipment maintenance and repair, helping to restore performance and reliability.