11 Maintenance
Inspect ignition and flame sense electrodes
1.Remove the ignition and both flame sense electrodes from the burner plate.
2.Remove any deposits accumulated on the ignition/ flame sense electrodes using sandpaper. If the electrodes cannot be cleaned satisfactorily, replace with new ones.
3.Replace ignition/flame sense electrodes, making sure the gaskets are 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.Navigate to the Setup Screen and check all settings. See Section 1 of the Crest Service Manual. Adjust settings if necessary. See Section 1 of the Crest Service 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 9 -
2.Verify cold fill pressure is correct and that operating pressure does not go too high.
Check burner flame
1.Inspect flame through observation windows.
2.If the flame is unsatisfactory at either high fire or low fire, remove and clean the burner. Clean the burner thoroughly using a vacuum cleaner or compressed air. Do not use compressed air to clean the burner if cleaning is performed inside a building.
Installation & Operation Manual
•Shut down the boiler:
-Follow the “To Turn Off Gas to Appliance” instructions for the boiler in Section 9 - Startup.
-Do not drain the boiler unless it will be exposed to freezing temperatures. If using freeze prevention fluid in system, do not drain.
3.Allow time for the boiler to cool to room temperature if it has been firing.
4.Remove the top access panel to remove the gas/air manifold assembly.
5.Remove the nuts securing the burner to the burner mounting plate. Remove the burner (FIG.
6.When replacing the burner, ensure gaskets are in good condition and positioned correctly (FIG.
7.When securing the burner, be sure to tighten the nuts, but DO NOT
Figure 11-2 Burner Assembly
INSULATION
AIR/GAS
MANIFOLD
MANIFOLD
GASKET
BURNER
ASSEMBLY
BURNER
GASKET
BURNER PLATE
FIBERBOARD
Check flame signal
1.At high fire of each combustion system, 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 electrodes 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 the Crest Service Manual for other procedures to deal with low flame signal.
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