Audi A4 B6 B7 A6 C5 Auxiliary Heating Unit Heater Matrix 4B2819011

Audi A4 B6 B7 A6 C5 Auxiliary Heating Unit Heater Matrix is an original cabin heating system component designed for mid-size and executive Audi models. It ensures stable, uniform heat dissipation in low-temperature conditions, supporting the main heating system and improving vehicle comfort. Thanks to its factory design, it fits the original cooling and ventilation system architecture without the need for any installation modifications.

Specifications and technical data

• SKU: RHD-4B2819011
• Mark: Audi
• Condition: Used
• OEM Part Number: 4B2819011
• Substitutable numbers: 4B2819011, 4B2 819 011
• Category: Other Air Conditioning & Heating

Purpose and function in the heating system

The presented auxiliary heater has been designed as a heating system component for the Audi A4 B6 and B7 generations and the Audi A6 C5 generation. Its task is to increase thermal efficiency during the engine warm-up phase and under high air conditioning system loads, which translates into reaching a comfortable interior temperature faster.

In practice, this means:

• more efficient cabin heating in low ambient temperatures,
• more stable maintenance of the set temperature in automatic air conditioning mode,
• better cooperation with the factory airflow control and air distribution system.

Original Audi construction

The auxiliary heater comes from the Audi production line, which means maintaining factory manufacturing standards and full compatibility with the cooling and ventilation system architecture in the listed models. The original design ensures:

• precise fit to the intended mounting space,
• compatibility with factory connectors and joints,
• maintenance of coolant and airflow parameters in accordance with the manufacturer's design.

As a result, this component can be used both as a replacement for a damaged heater and as part of broader heating system maintenance, without interfering with the vehicle's installation.

Condition and service application

The offered heater is a secondary market component, which allows for economical repair of the heating system while maintaining the original manufacturer's specifications. This type of solution is particularly beneficial for older generations of Audi A4 and A6, where it is important to combine reasonable service costs with maintaining correct system operating parameters.

The component will prove useful in the following applications:

• replacement of a damaged or leaking auxiliary heater,
• restoring full heating system efficiency after modernization or overhaul,
• servicing vehicles operated under high thermal load conditions.

Benefits of using an original auxiliary heater

Using an original component in the Audi A4 B6/B7 and A6 C5 allows for maintaining the consistency of the entire heating and air conditioning system. Compared to generic replacements, the factory auxiliary heater offers:

• predictable operating parameters consistent with the manufacturer's specifications,
• lower risk of issues with venting and coolant flow,
• better integration with the existing installation and equipment.

For the user, this means stable thermal comfort in the interior, which is particularly important in vehicles used year-round and on longer routes.

Expanding Audi heating system maintenance

If you are planning a comprehensive repair or modernization of the heating and air conditioning area in your Audi and need other components from the same group, such as heaters, cooling system hoses, or airflow control elements, check the available parts in the Other Audi category.

For users interested in a broader look at the structural differences between standard and sports versions, including solutions in terms of cooling, brakes, and chassis, the following article may be helpful: Audi RS vs other models – what is hidden under the hood and chassis?, which organizes knowledge about the specifics of individual Audi variants.