Worcester Bosch Washer 5/16 Inch 1.2mm 87161405090

This is a flat sealing washer manufactured by Worcester Bosch, measuring 5/16 inch across with a thickness of 1.2mm. It sits at a joint face and compresses under load to stop water or gas-path fluid escaping past a threaded connection or mating surface. The washer is used across the Worcester Boilerhouse and Danesmoor ranges, where it forms part of the sealing arrangement on the appliance's pipework and fittings.

• A weep or drip at the joint the washer seals, often showing as a bead of water on the fitting
• Damp staining, crusting or limescale tracking around the connection
• The washer sitting flattened, hardened or cracked once the joint is opened
• Corrosion or pitting on the washer face or the mating surface beneath it
• A joint that will not seal cleanly after being remade with the old washer in place

• Confirm your appliance model and, where available, the serial number against the compatibility list before ordering
• Check the old washer against the previous number ZGWSH050 and the alternative number 1017373 to be sure of the match
• If the joint is being opened as part of a wider repair, check whether any other seals on the same assembly also need renewing