She turns off the flame and allows it to cool down for several minutes. She then takes the business card and checks the alignment of the burner head. Then she inserts the card in the slot and moves it back and forth, up and down, to remove any residues from flame combustion that could be blocking the burner slot. Ideally, she would like to have air flowing through the burner to remove the residues, rather than allowing them to drop into the burner chamber. However, on this instrument she cannot control the air flow manually. Having cleaned and aligned the burner head, she turns the flame back on and observes a smoother and somewhat more stable flame as shown here. However she still notices some flickering, undoubtedly due to the exhaust flow that is greater than it should be. That will have to be dealt with later, by repositioning the exhaust hood. Unfortunately, when the exhaust was designed, no damper was placed in the flow line. Had that been done, her problem could be easily solved by adjusting the flow with the damper. Still, she has one problem left. When distilled water is introduced into the flame, a pinkish color appears while when no solution is introduced, the flame is blue. What is the problem and the solution?

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