Vaillant Gas Pipe (Bottom) 0020218791

The Vaillant gas pipe (bottom) is a manufacturer pipe section for the gas-carrying circuit on Vaillant VUW 356/5-7 combination boilers. It is identified by Vaillant part number 0020218791 and sits at the lower connection point of the gas train. Its function is to carry gas to the appliance's gas valve assembly as part of the sealed gas path.

• A smell of gas or a drop in pressure on a tightness test traced to the lower gas pipework
• Visible corrosion, pitting or surface degradation on the pipe
• Staining, discolouration or residue around the pipe joints or unions
• Physical damage, distortion or a kinked section of pipe
• A joint that will not seal correctly after reassembly

• Confirm the appliance model and GC number against the fitment list above
• Check the part number 0020218791 matches the pipe currently fitted
• Verify the pipe position — this is the bottom gas pipe, not an upper or alternative section
• Work on gas-carrying components must be carried out by a Gas Safe registered engineer