Worcester Bosch Washer 87103020420

This is a Worcester Bosch washer, part number 87103020420. It is a sealing component used in Greenstar CDI and Greenstar ErP Classic Regular appliances, which include conventional and regular variants in both LPG and NG. It is classified under gaskets, O-rings, seals and washers. Its function is to create a watertight seal at a connection point within the appliance. The washer is a small but critical component in the appliance's water circuit, helping to maintain system integrity. It is supplied as a spare part for service and repair. The part number 87103020420 is the primary identifier for this washer.

• Water leaking from the appliance connection point, often visible as drips or pooling water.
• Visible cracks, hardening or deformation of the washer material.
• Dripping or pooling water beneath the boiler, indicating a failed seal.
• Loss of system pressure, which may trigger boiler lockout.
• Recurring leaks after tightening connections, suggesting the washer is no longer sealing effectively.

• Check your appliance's GC number against the compatibility list to confirm fit.
• The alternative part number 1012385 may be listed on older documentation or parts lists.
• Confirm the part number 87103020420 matches the part you are replacing.
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.