The UNF3 Nitrogen Flow Indicator is a visual tool that confirms the flow of nitrogen gas through the copper lines during brazing. Flowing nitrogen gas through copper tubing while brazing displaces the oxygen, preventing oxidation and the resulting scale that would contaminate refrigerant. Nitrogen flow is visually confirmed by the float ball in the flow indicator tube. If the ball does not rise in the tube, then there is static pressure and the oxygen is not being displaced.

Uniweld Products Inc., 2850 Ravenswood Road, Ft. Lauderdale, FL 33312; 800-323-2111 or 954-584-2000; www.uniweld.com