When it comes to using AN fittings on hard lines, both flaring and compression fittings are common methods, and each has its pros and cons.
Flaring:
Pros:
Provides a reliable and strong connection.
Can be considered a traditional method, widely used and accepted.
Cons:
Requires a double flaring tool, which may take some practice to use correctly.
If not done properly, there is a risk of the flare splitting or leaking.
Compression Fittings:
Pros:
Generally easier and quicker to install.
No need for a flaring tool.
Cons:
Some enthusiasts and professionals may prefer flaring for critical applications like fuel lines due to the perceived reliability.
For a fuel system, especially one that involves high-pressure situations, some people may lean towards flaring for the added security and strength of the connection. However, many modern compression fittings are designed to handle high-pressure applications and can provide a reliable seal.