Drain Plug O-Ring for Counter Current System STP-SS - 7017373

Bosta – Drain Plug O-Ring for Counter Current System STP-SS (No. 9)

This is the genuine Bosta replacement O-ring for the drain plug of the Counter Current System STP-SS — referenced as item No. 9 in the official Bosta STP-SS spare parts diagram. It provides a watertight seal at the drain plug port, preventing leaks and protecting the system during normal operation and seasonal winterisation.

Compatibility

Designed specifically for the Bosta Counter Current System type STP-SS. Always cross-reference the part number (7017373) and position No. 9 in your system’s spare parts diagram before ordering, as the STP-SS range includes several O-rings of different sizes used in different positions.

Why Genuine Matters

Using a genuine Bosta O-ring ensures the correct material compound, hardness, and dimensional tolerances for a reliable, long-lasting seal. Off-spec substitutes risk swelling, cracking, or an improper fit that can lead to persistent leaks at the drain plug — a common source of water loss in counter-current systems.

Installation

Before fitting, remove the drain plug completely and clean the seating surface. Lightly lubricate the new O-ring with a silicone-based grease, seat it evenly in the groove, and refit the drain plug without over-tightening. Inspect for leaks after the system is returned to pressure.