What should the pilot flame look like if functioning correctly?

When a pilot flame is functioning correctly, it should appear clean, blue, and well defined. This color indicates an efficient and complete combustion process, where the gas is burning properly with an appropriate air-to-fuel ratio. A blue flame signifies that there is enough oxygen being supplied to the pilot, resulting in a stable and efficient flame with minimal carbon monoxide production.

The cleanliness of the flame is also significant; ideally, it should be free of yellow tips or excessive flickering, which can suggest incomplete combustion or a lack of proper gas flow. A well-defined pilot flame means it is stable and correctly positioned to ignite the main burner when needed, contributing to safe and effective operation of the gas appliance.