Description
Astralpool o-ring 118 x 4 mm 4405010437
The Astralpool o-ring 118 x 4 mm 4405010437 is a replacement elastomer seal used to restore watertightness on compatible Astralpool pool
equipment. With an internal diameter of approximately 118 mm and a 4 mm cross section, it is designed to fit the dedicated groove on
selected lids, flanges or unions and provide a reliable, long lasting seal under normal filtration pressure.
Main features of the Astralpool o-ring 4405010437
- Original style o-ring with 118 mm inner diameter and 4 mm section.
- Designed for Astralpool pool components that specify reference 4405010437.
- Manufactured from elastomer suitable for treated pool water.
- Round cross section for even compression in standard o-ring grooves.
Function in the filtration system
This o-ring is mounted in a machined or moulded groove between two mating parts, such as a pump lid, inspection cover, union or flange.
When the parts are assembled and tightened, the o-ring is compressed slightly, filling the gap and preventing water or air from passing
through the joint.
- Provides a watertight and airtight seal along the contact surface.
- Helps maintain stable suction and discharge pressure in the circuit.
- Reduces the risk of drips and air ingress in the technical room.
Compatibility and typical applications
The Astralpool o-ring 118 x 4 mm 4405010437 is intended for use on Astralpool pool pumps, filters or accessories that list this reference
in the exploded view or spare parts list. The dimensions are matched to the original groove, so the seal can be installed directly
without modification.
- Suitable for Astralpool components that specify 4405010437 as sealing o-ring.
- Ideal for replacing worn or flattened seals on compatible lids or unions.
- Recommended when refurbishing older equipment to restore full sealing performance.
Always confirm the code in the documentation or on the parts diagram of your specific model to ensure the o-ring size is correct.
When to replace the o-ring 118 x 4 mm
O-rings are consumable parts that gradually lose elasticity under the combined effects of pressure cycles, temperature changes and pool
chemicals. A tired or damaged seal can lead to leaks, air entry and unstable pump operation.
- Visible cracks, cuts or rough areas on the o-ring surface.
- Flattened, shiny appearance from long term compression in the groove.
- Persistent seepage or air bubbles at the joint even after careful tightening.
- Disassembly of the component for maintenance, where reusing the old seal is not recommended.
Installation and maintenance tips
Fitting the Astralpool o-ring 118 x 4 mm 4405010437 is a simple operation, but careful handling helps ensure a reliable seal and longer
service life.
- Switch off the pump and depressurise the system before opening any sealed component.
- Remove the old o-ring and clean the groove and contact surfaces to eliminate dirt and scale.
- Check that the new o-ring is clean, undamaged and correctly sized for the groove.
- Place the o-ring gently into the groove, making sure it is not twisted or stretched unevenly.
- Apply a thin film of silicone based lubricant suitable for pool seals if desired, to reduce friction and ease assembly.
- Reassemble the parts and tighten evenly, avoiding excessive force that could crush or deform the o-ring.
After reassembly, restart the filtration system and inspect the joint carefully during the first minutes of operation to confirm that the
area remains completely dry and that no air is being drawn into the circuit.
Good practice for longer o-ring life
A few routine habits help the Astralpool o-ring 118 x 4 mm 4405010437 provide efficient sealing over many seasons.
- Maintain balanced water chemistry to limit chemical stress on elastomer components.
- Clean sealing surfaces before closing lids or unions to avoid pinching grains of sand or dirt.
- Do not use tools to overtighten closures; hand tightening is usually sufficient.
- Replace seals preventively during major services rather than waiting for visible leaks.
With a correctly installed Astralpool o-ring 118 x 4 mm 4405010437, compatible pool equipment recovers secure, watertight joints that
support stable, efficient filtration in daily use.
