Lochinvar 81-286 Inspect ignition and flame sense electrodes, Check ignition ground wiring

2 Maintenance (continued)

Inspect ignition and flame sense electrodes

1.Remove the ignition and flame sense electrodes from the boiler heat exchanger access cover.

2.Remove any deposits accumulated on the ignition/ flame sense electrode using sandpaper. If the electrodes cannot be cleaned satisfactorily, replace with new ones.

3.Replace ignition/flame sense electrode, making sure gasket is in good condition and correctly positioned.

Check ignition ground wiring

1.Inspect boiler ground wire from the heat exchanger access cover to ground terminal strip.

2.Verify all wiring is in good condition and securely attached.

3.Check ground continuity of wiring using continuity meter.

4.Replace ground wires if ground continuity is not satisfactory.

Check all boiler wiring

1.Inspect all boiler wiring, making sure wires are in good condition and securely attached.

Check control settings

1.Set the SMART SYSTEM control module display to Parameter Mode and check all settings. See Section 1 of this manual. Adjust settings if necessary. See Section 1 of this manual for adjustment procedures.

2.Check settings of external limit controls (if any) and adjust if necessary.

Perform start-up and checks

1.Start boiler and perform checks and tests specified in Section 10 - Start-up of the Knight Boiler Installation and Operation Manual.

2.Verify cold fill pressure is correct and that operating pressure does not go too high.

Service Manual

Check burner flame

1.Inspect flame through observation window.

2.If the flame is unsatisfactory at either high fire or low fire, turn off boiler and allow boiler to cool down. Remove the burner and clean it thoroughly using a vacuum cleaner or compressed air. Do not use compressed air to clean burner if performed inside a building.

3.Remove the burner, reference FIG. 2-2 below.

4.When replacing the burner, ensure gasket is in good condition and positioned correctly (FIG. 2-2).

Figure 2-2Burner Assembly

Check flame signal

1.At high fire the flame signal shown on the display should be at least 10 microamps.

2.A lower flame signal may indicate a fouled or damaged flame sense electrode. If cleaning the flame sense electrode does not improve, ground wiring is in good condition, and ground continuity is satisfactory, replace the flame sense electrode.

3.See Section 3 - Troubleshooting in this manual for other procedures to deal with low flame signal.