Crestron electronic 2 Inspect ignition and flame sense electrodes, Check ignition ground wiring

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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 - Start-up.

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. 11-2).

6.When replacing the burner, ensure gaskets are in good condition and positioned correctly (FIG. 11-2).

7.When securing the burner, be sure to tighten the nuts, but DO NOT over-tighten. Tighten the nuts to a torque setting of no more than 6.2 ft.-lbs. When securing the burner mounting plate be sure to tighten the nuts, but DO NOT over-tighten. Tighten the nuts to a torque setting of no more than 15.5 ft.-lbs.

Figure 11-2Burner 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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Contents Save this manual for future reference Contents When servicing boiler Please read before proceedingCrest How it works BlowersCrest How it works Models 1.5 2.0 2.5 3.0 Ratings Crest Ahri RatingInstallation must comply with Determine boiler locationBefore locating the boiler, check Provide clearancesProvide air openings to room Flooring and foundationVent and air piping Prevent combustion air contaminationAreas likely to have contaminants When using an existing vent system to install a new boilerProducts to avoid When removing a boiler from existing common vent system Remove boiler from wood pallet 7Combustion Air from Outside Single Opening Minimum Recommended Combustion AIR Supply to Equipment Room Optional room air General ventingDirect venting Install vent and combustion air piping Air inlet pipe materialsApproved Stainless Steel Vent Manufacturers Make Model Air intake/vent connectionsRemoving from existing vent Common venting Vertical direct venting Vent/air termination verticalDetermine location Prepare roof penetrationsMultiple vent/air terminations 4Alternate Vertical Terminations with Multiple BoilersSidewall direct venting Vent/air termination sidewallPrepare wall penetrations 2Clearance to Doors and WindowsRoom air 4Multiple Vent Terminations must also comply with FigureHydronic piping 20F 40F 60F Circulator sizingModel Near boiler piping components System Multiple Boilers Common Header Primary / Secondary Flow For all equipment and detailing required by local codes Hydronic piping Model Gas Inlet Size Connecting gas supply pipingGas connections Natural gas Propane GasGAS Piping Size Chart Check inlet gas supplyGas valve replacement Gas PressureLine voltage connections Field wiringInstallation must comply with Enable Outdoor temperature sensorLouver proving switch Low voltage connectionsAuxiliary switch 1 Alarm contactsWiring of the cascade System supply sensorWiring FieldCondensate disposal Condensate drainFreeze protection when used Start-upCheck/control water chemistry Fill and test water systemCheck for gas leaks Check thermostat circuitsInspect condensate system Inspect/check condensate lines and fittingsFinal checks before starting the boiler Start the boilerIf boiler does not start correctly Check system and boilerFor Your Safety Read Before Operating Set space heating operation Gas Natural Gas Propane ValveSet clock Verify HWG circulator mode Set HWG target temperatureConfiguration of the cascade Operating information GeneralProtection features Boiler temperature regulation Outdoor reset operation, if usedCascade Sequence of operation Crest control module Home Screen2Main Menu Screen Maintenance Maintenance and annual startup Service technicianOwner maintenance See the Crest User’s Information Manual for InstructionsMaintenance Flue vent system and air piping Check water systemCheck expansion tank Check boiler relief valveCheck ignition ground wiring Check all boiler wiringCheck control settings Check flame signalCleaning boiler heat exchanger Review with ownerHandling ceramic fiber materials Niosh stated First AidDiagrams Integrated Control2Wiring Diagram
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