Figure 39: Sequence of Operation
I.Sequence of Operation. See Figure 39. If boiler fails to operate properly, see Troubleshooting Tree in Section IX: Service.
J.Check pilot burner flame. See Figure 41. Flame should be steady, medium hard blue enveloping 3/8 to ½ inch of sensing probe.
K.Check main burner flame. See Figures 40. Flame should have clearly defined inner cone with no yellow
Figure 40: 1 Inch Main Burner flame
Figure 41: Pilot Burner Flame
tipping.
L. Check thermostat operation. Raise and lower temperature setting to start and stop boiler operation.
M.Check ignition control module
N.Check low water cutoff (if so equipped).
1.Adjust thermostat to highest setting.
2.With boiler operating, open drain valve and slowly drain boiler.
3.Main burners and pilot burner will extinguish and blower will stop when water level drops below low water cutoff probe. Verify limit, thermostat or other controls have not shut off boiler.
4.Adjust thermostat to lowest setting. Refill boiler.
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