Zodiac - O-ring 240x3 NBR 70 - R0818300

Zodiac – O-ring 240×3 NBR 70 – R0818300

The Zodiac R0818300 is a genuine OEM replacement O-ring designed for use in Zodiac pool equipment. This sealing ring has a diameter of 240 mm with a cross-section of 3 mm and is manufactured from NBR 70 (Nitrile Butadiene Rubber, Shore hardness 70). NBR is a synthetic rubber compound widely used in hydraulic and pneumatic sealing applications due to its excellent resistance to oils, fuels, and a broad range of pool chemicals. The Shore 70 hardness rating indicates a medium-firm elastomer that provides a reliable, long-lasting seal under standard operating pressures encountered in pool circulation systems.

O-rings of this type function by creating a compressed seal between two mating surfaces — typically between a lid, cover plate, or housing component and its body. When correctly seated and compressed, the NBR 70 material conforms to the mating surfaces and prevents water or air from bypassing the sealed joint. Over time, exposure to pool chemicals, UV radiation, and mechanical compression cycles causes O-rings to harden, crack, or deform, leading to leaks. Replacing a worn O-ring with a genuine Zodiac part restores the original sealing performance and prevents water loss or pressure drop in the system.

Technical characteristics and construction

The R0818300 O-ring measures 240 mm in inner diameter with a cord thickness of 3 mm, making it a large-format sealing ring suited to substantial housing covers or lid assemblies. The NBR 70 compound offers good resistance to chlorinated water, common pool treatment chemicals, and moderate temperatures, which are typical conditions in both residential and commercial pool environments. Using a genuine Zodiac replacement part ensures correct dimensional tolerances, material specification, and compression behaviour — all critical factors for a leak-free installation. Aftermarket O-rings with slightly different hardness or dimensional tolerances can result in premature failure or incomplete sealing.

Suitability and application

This O-ring is intended as a direct replacement spare part for Zodiac pool equipment that uses a 240×3 mm NBR 70 sealing ring. It is suitable for residential and commercial pool installations where Zodiac branded pumps, filters, or related hydraulic equipment are in use. If you are servicing Zodiac pool equipment and have identified a damaged, hardened, or leaking O-ring of these dimensions, the R0818300 is the correct genuine replacement. Always ensure the seating groove is clean and free of debris before fitting the new O-ring, and apply a thin layer of silicone grease to aid installation and extend service life.