Description
Astralpool diffuser 4405010411
The Astralpool diffuser 4405010411 is the original hydraulic insert for selected Astralpool pool pumps. Mounted between the impeller and
the pump body, it guides the water flow leaving the impeller, turning kinetic energy into pressure and helping the pump deliver its
designed performance curve quietly and efficiently.
Role of the Astralpool diffuser 4405010411
Inside the wet end of the pump, the diffuser surrounds the impeller and shapes the passage the water follows as it exits the blades.
Its internal channels gradually slow down the flow and convert velocity into useful pressure for the filtration circuit. A diffuser in
good condition ensures stable pressure at the filter, supports good priming and helps keep noise and vibration under control.
Design and construction
The Astralpool diffuser 4405010411 is moulded from durable plastic designed for long term contact with treated pool water. Its geometry
is matched to the corresponding impeller and pump body, so that clearances and passages are correct when all components are assembled in
the original configuration.
- High quality plastic body resistant to normal pool water chemistry.
- Internal guide vanes and chambers optimised for the matching impeller.
- Precise locating features to position the diffuser in the pump housing.
- Sealing surfaces adapted to the original gaskets and o-rings of the pump.
Compatibility and typical applications
This diffuser is intended for use on specific Astralpool pool pumps that list reference 4405010411 in their exploded view or spare parts
list. It is particularly suited to residential filtration systems using sand, glass or cartridge filters where original hydraulic
performance needs to be restored after repair.
- Suitable for Astralpool pumps that specify diffuser 4405010411.
- Ideal when replacing a worn, cracked or eroded diffuser.
- Recommended during major overhauls together with a new impeller and mechanical seal.
Always verify the pump model and power rating on the identification label and compare with the official parts diagram to confirm that
this is the correct diffuser for your unit.
When to replace the diffuser
Although protected inside the pump, the diffuser is exposed to high velocity water, fine abrasion and occasional cavitation. Over time,
this can alter its shape and affect performance. Mechanical damage during previous disassembly is also common.
- Visible cracks or broken fins on the internal guide vanes.
- Erosion, pitting or rough areas in the flow passages.
- Deformation that prevents the diffuser from seating correctly in the housing.
- Loss of pressure or noisy operation even after cleaning the prefilter and filter.
Replacing a damaged diffuser with the original Astralpool diffuser 4405010411 helps the pump recover its designed flow and pressure
characteristics and can noticeably improve overall filtration quality.
Installation recommendations
Installing the Astralpool diffuser 4405010411 is done with the pump fully isolated electrically and hydraulically. The work is usually
combined with other maintenance tasks such as mechanical seal replacement or impeller inspection.
- Switch off and isolate the pump, close valves and drain the housing.
- Remove the prefilter lid and basket, separate the wet end from the motor and unscrew the impeller.
- Take out the old diffuser and clean the seating area in the pump body.
- Position the new diffuser, making sure all locating tabs and grooves engage correctly.
- Reinstall the impeller, seal plate and remaining components following the manufacturer sequence.
- Reassemble the pump, prime the prefilter and check for leaks and stable pressure on start up.
Careful assembly and respect of torque limits on plastic parts help the new diffuser and surrounding components deliver a long service
life in daily operation.
