www.desatech.com119169-01E 17BURNER FLAME PATTERNWARNING: If yellow tippingoccurs, your heater could pro-duce increased levels of carbonmonoxide.NOTICE: Do not mistake orangeflames with yellow tipping. Dirtor other fine particles enter theheater and burn causing briefpatches of orange flame.Figure 24 shows a correct burner flame pat-tern. Figure 25 shows an incorrect burnerflame pattern. The incorrect burner flamepattern shows yellow tipping of the flame.It also shows the flame higher than 1/2 theglass panel height.If burner flame pattern is incorrect, as shownin Figure 25• turn heater off (see To Turn Off Gas ToAppliance, page 16)• see Troubleshooting, page 19INSPECTING HEATERCheck pilot flame pattern and burner flamepattern often.PILOT FLAME PATTERNFigure 22 shows a correct pilot flame pattern.Figure 23 shows an incorrect pilot flame pat-tern. The incorrect pilot flame is not touchingthe thermocouple. This will cause the thermo-couple to cool. When the thermocouple cools,the heater will shut down.If pilot flame pattern is incorrect, as shownin Figure 23• turn heater off (see To Turn Off Gas to Ap-pliance, page 16)• see Troubleshooting, page 19Note: The pilot flame on natural gas units willhave a slight curve, but flame should be blueand have no yellow or orange color.Figure 23 - Incorrect Pilot Flame PatternFigure 22 - Correct Pilot Flame PatternThermocouplePilot BurnerPilotBurnerThermocoupleBlue FlameYellow FlameFigure 24 - Correct Burner Flame PatternYellowTippingFigure 25 - Incorrect Burner FlamePattern1 /2 GlassHeight1 /2 GlassHeightBlueFlame