Wisa Sphinx Side Entry Cistern Fill Valve Diaphragm Washer — 8050800311
The Wisa Sphinx 8050800311 is the authentic replacement rubber float valve membrane designed specifically for original Wisa side-entry and universal inlet fill valves. When a toilet cistern continuously runs into the pan, trickles constantly, or fills up with a loud whistling noise, it is typically caused by a split, distorted, or perished diaphragm. Swapping out the degraded washer with this factory-original component quickly restores a silent, reliable water shut-off without the need to replace the entire valve mechanism.
Identification Guide:
MPN: 8050800311 (Alt: 8050.800311 / 8050.123024) | EAN: 8711778164864 | Diameter: 29mm (28.5mm profile) | Total Height: 20mm (base to cone tip)
Key Features
- Precision Moulding: Equipped with a built-in hard plastic support plate to guarantee structural strength under high fluid pressures.
- Wisa Specific Fit: Tailored exclusively to the internal profile of Wisa fill valves; will not seal correctly in other standard universal valves.
- High Elastomer Resilience: Crafted from chloramine-resistant rubber compounds designed to combat chemical deterioration from water treatments.
- Cost-Effective Fix: Prevents premature, complex plumbing line alterations by safely servicing the existing fill valve body.
Installation Note
Isolate the water supply before attempting installation. Carefully unscrew the circular retaining cap located on the side entry inlet valve body, remove the old membrane, and clean any collected sand, grit, or limescale away from the valve seat. Insert the new 8050800311 washer firmly in place, ensuring the plastic cone points into the guide, and hand-tighten the retention cover firmly to secure.