Sime Connecting Pipe Expansion Vessel 6227644

The Sime 6227644 connecting pipe links the expansion vessel to the hydraulic circuit on a range of Sime gas boilers. It carries water between the vessel and the boiler's primary system, allowing the vessel to absorb expansion as the system heats. The part is specific to the appliance families listed below.

• Water weeping or staining at the pipe unions or along the pipe run
• Pressure loss on the primary circuit that cannot be traced to other components
• Corrosion or pitting visible on the pipe surface
• Scale or debris build-up restricting flow to or from the expansion vessel
• Expansion vessel failing to hold charge because the connection is blocked or leaking

• Confirm the boiler model and serial number against the fitment list above
• Inspect the existing pipe and unions to identify whether the fault is the pipe or the vessel itself
• Check the expansion vessel charge pressure before replacing the connecting pipe
• Have new sealing washers or O-rings to hand if the existing ones are disturbed during removal