Siamp Eco Deluxe Optima S and 99T BP Delayed-Action WC Component Pack
The Siamp Optima S/99T BP 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 37941110. 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 S/99T BP |
| Manufacturer part no. | 37941110 |
| Pack quantity | 1 |
Set the flush valve’s telescopic overflow and the inlet’s telescopic height to the cistern before fitting; release the delayed-action float box with its small white screw to set the water level, then lock it again. 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. Maximum water level is 20 mm below the overflow. Use no limescale or chlorine cleaners in the cistern.
Specification sheets: Optima S flush valve (PDF) · Compact OD 99T BP filling valve (PDF) · Installation manual (PDF) · See related WC cistern parts.
