What is a prime cause of lifting flames in gas burners?

Lifting flames in gas burners can primarily be attributed to too much gas pressure. When the gas pressure is excessive, it can lead to an overly rich fuel mixture, which results in an unstable flame. This instability can cause the flame to lift off the burner ports, creating a situation where the flame is not properly anchored, potentially leading to inefficient combustion and increased emissions.

In gas burners, achieving the right balance between gas pressure and air supply is crucial for maintaining a stable flame. When the pressure is excessive, it disrupts this balance, leading to flame characteristics that are undesirable, such as lifting flames. Maintaining proper gas pressure ensures that the burner operates efficiently, sustaining a well-combusted flame that remains stable.

Other factors, such as air supply and draft, also play a role in flame stability, but excess gas pressure is a primary cause of lifting flames, making it the most relevant answer in this context.