Siamp Optima 50 and 99B WC Flush and Fill Component Pack
The Siamp Optima 50/99 component pack combines the matched filling and flushing parts listed below for a coordinated WC cistern repair. It is supplied as one manufacturer pack under Siamp part number 37998007. Replacing both mechanisms together is useful where the cistern needs a broader internal service. Check both valve arrangements against the cistern before ordering.
| Brand | Siamp |
| Model | Optima 50/99 |
| Manufacturer part no. | 37998007 |
| Pack quantity | 1 |
Hand-tighten both the flush valve nut and the inlet backnut to the ceramic and add no more than a quarter turn — over-tightening damages either mechanism and is not covered by Siamp’s warranty. Use no sealing paste or compound. Tap connector not supplied; Siamp requires an approved check valve at the supply connection. Set the water level 20 mm below the overflow, mount the button with its nut and clip the cable case before replacing the lid. Use no limescale or chlorine cleaners in the cistern.
Specification sheets: Optima 50 flush valve (PDF) · Compact 99B filling valve (PDF) · Installation manual (PDF) · See related WC cistern parts.
