Vaillant Automatic Air Vent 0010033857

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The Vaillant Automatic Air Vent (Part No. 0010033857) is a critical internal component designed to automatically purge air from the boiler's primary heating circuit. Maintaining an air-free system is essential for protecting the internal pump from cavitation, ensuring efficient heat transfer, and preventing the "banging" or "gurgling" noises associated with air pockets. This high-quality OEM part is a direct replacement for the air vents found in modern Vaillant ecoTEC and ecoFIT ranges.

Key Features and Specifications
Automatic Operation: Features an internal float mechanism that allows air to escape while ensuring the system remains watertight under pressure.

Genuine Vaillant Part: Manufactured to the exact specifications required for a perfect seal and reliable operation within Vaillant’s hydraulic blocks.

System Protection: By removing oxygen and air bubbles, it helps prevent internal corrosion and significantly extends the lifespan of the heat exchanger and pump.

High-Temperature Construction: Built from heat-resistant polymers and high-grade seals to withstand constant exposure to primary heating water.

Compatibility: This is the current part used across the vast majority of the ecoTEC and ecoFIT Pure ranges.

Boiler Compatibility
This Automatic Air Vent (AAV) is used extensively in Vaillant's modern wall-hung boiler lineup. Common compatible models include:

ecoTEC Plus (All Models): 612, 615, 618, 624, 630, 637, 824, 831, 832, 835, 837, 838, 937, 938.

ecoTEC Pro (All Models): 24, 28, 30.

ecoFIT Pure: 612, 615, 618, 625, 630, 825, 830, 835.

Home Glow: Various models.

Technical Tip: If your boiler is losing pressure or you notice water dripping from the bottom of the casing, a leaking Automatic Air Vent is often the culprit. Over time, system debris can prevent the internal float from sealing correctly.

Maintenance and Installation Advice
When replacing the AAV, it is often necessary to isolate the boiler and partially drain the primary circuit. It is highly recommended to check the condition of the system water at the same time. If the old vent is clogged with black magnetite (sludge), a full system flush and the addition of a high-quality inhibitor are advised to prevent the new vent from failing prematurely.

Essential Companion Products
To ensure a complete and professional repair, the following genuine Vaillant and maintenance products are recommended:

Direct Product Link: Vaillant Automatic Air Vent - 0010033857

System Pressure Protection: Vaillant Pressure Relief Valve (3 Bar) - 178985

System Protection: Fernox F1 Central Heating Protector (to prevent future AAV clogging).

Flow/Return Monitoring: Vaillant NTC Sensor (19-3592)

Specialist Support and Local Collection
Are you experiencing "F.22" or "F.24" faults on your Vaillant boiler? These are often related to air in the system or low water pressure. Our trade counter team can help you identify if this Automatic Air Vent is the correct solution for your specific fault code.

Visit our trade counter and Bathroom Showroom at 61 Fullers Road, E18 2QB for expert technical advice and quick access to genuine Vaillant spares.