Vaillant Air Separator 0020268776

The Vaillant air separator, part number 0020268776, is a hydraulic component fitted within the appliance circuit of Vaillant VU 446/5-5 and VU 606/5-5 appliances. It removes entrained air from the heating water before it circulates through the boiler and system, protecting the pump, heat exchanger and other hydraulic parts from air-related noise, corrosion and poor heat transfer.

• Persistent gurgling, rushing or trickling noises from the appliance or pipework after repeated venting
• Air continually collecting at high points in the system, with radiators needing frequent bleeding
• Pump noise or intermittent pump operation caused by air not being separated from the circuit water
• Localised overheating, temperature swings or boiler lockout linked to poor circulation through the hydraulic block
• Visible leakage, corrosion or physical damage at the separator body or its connections

• Confirm the appliance model and GC number against the data badge before ordering
• Check the part number 0020268776 against the manufacturer's parts list for your appliance
• Inspect the surrounding hydraulic components and seals, as air ingress often originates elsewhere in the circuit
• Verify the appliance variant, as VU 446/5-5 and VU 606/5-5 models can differ by build year