Alpha Gasket 3.018596

This is a gasket, O-ring, seal or washer from Alpha, designed for use in their CD series of gas boilers. It provides a sealing function at joints and connections within the appliance, helping to prevent leaks and maintain correct operation. The part carries the manufacturer part number 3.018596. As a sealing component, it is essential for maintaining system pressure and preventing fluid or gas escape at mating surfaces. In Alpha CD boilers, it may be used in locations such as pump connections, heat exchanger joints, and pipe unions. A worn or damaged seal can lead to leaks, pressure loss, and inefficient operation. This component is typically replaced during routine servicing or when a leak is detected. It is a consumable item that may degrade over time due to heat, pressure, and chemical exposure.

• Visible water or gas leaks at the joint where the seal is fitted.
• The gasket, O-ring or washer appears hardened, cracked or deformed.
• Persistent pressure loss or intermittent boiler lockouts.
• Corrosion or discolouration around the sealing surface.
• Water marks or staining around the boiler casing.
• Boiler pressure dropping without visible leaks elsewhere.
• Boiler making unusual noises due to air ingress.
• Overheating due to loss of system pressure.

• Check the GC number and serial number of your appliance to confirm compatibility.
• Note the alternative number 1257801 when cross-referencing.
• If replacing a seal in a gas-carrying component, ensure the gas supply is isolated and the system is purged before and after work.
• Confirm whether a complete gasket set is required for your repair.