Worcester O Ring 87161138330

Worcester

The Worcester O-Ring (Part No. 87161138330) is a genuine OEM (Original Equipment Manufacturer) hydraulic seal designed for a wide variety of connections within Worcester Bosch Greenstar boilers. This high-quality rubber seal is engineered to maintain a watertight boundary between internal components, specifically where plastic hydraulic blocks and copper pipework interface. Its precision-molded profile ensures it can withstand both high system pressure and the constant thermal expansion and contraction of the boiler's water circuits.

Key Features and Specifications
High-Grade EPDM Rubber: Manufactured from durable, heat-resistant EPDM, which is specifically chosen for its longevity in hot water applications and resistance to system chemicals.

Precision Geometry: Designed with the exact cross-sectional diameter required to fit Worcester's "push-fit" and "flanged" hydraulic connections.

Genuine Worcester Bosch Part: Ensures the O-ring has the correct shore hardness (flexibility) to create a perfect seal without being crushed or pinched during installation.

Universal Application: Used in multiple locations within the boiler, including the flow turbine assembly, return manifolds, and heat exchanger pipework.

Leak Prevention: Acts as the primary defense against internal water leaks that can damage sensitive electrical components and PCBs.

Boiler Compatibility
This O-ring is one of the most common seals found across the Worcester Greenstar range. Compatible models include:

Greenstar i (Combi & System): 24i, 25i, 28i, 30i.

Greenstar i Junior: 24i Junior, 28i Junior.

Greenstar Si & Si Compact: 25Si, 29Si, 30Si.

Greenstar CDi (Classic & Compact): 27CDi, 30CDi, 35CDi, 37CDi, 42CDi.

Greenstar Ri: 12Ri, 15Ri, 18Ri, 24Ri.

Technical Tip: Whenever a hydraulic component is removed—such as the flow turbine or a pipe—the associated O-ring should always be replaced. Reusing an old O-ring is a leading cause of "weeping" leaks, as the rubber loses its elasticity and takes a permanent "set" over time.

Installation Advice
Before fitting the new 87161138330 O-ring, the engineer should ensure the receiving groove is perfectly clean and free of limescale or old rubber residue. A small amount of WRAS-approved silicone grease should be applied to the O-ring to aid installation; this prevents the seal from twisting or tearing as the components are pushed together.

Essential Companion Products
To ensure a professional and permanent hydraulic repair, the following genuine Worcester parts are frequently checked alongside this O-ring:

Hydraulic Interface: Worcester Flow Turbine Adapter - 8716122264

The Sensor: Worcester Flow Turbine - 87161072230

Secure Fastening: Worcester Retaining Nut - 87161066830

Wiring Security: Worcester Clip Wire Flow Connector - 87161483490

Specialist Support and Local Collection
Are you noticing a small drip inside your boiler or a loss of system pressure? Our trade counter team can help you identify exactly which O-rings and gaskets are needed for your specific repair based on your boiler's GC number.

Visit our trade counter and Bathroom Showroom at 61 Fullers Road, E18 2QB for expert technical advice and quick access to the full range of genuine Worcester Bosch seals.