12 Maintenance (continued)
Check expansion tank
1.Expansion tanks provide space for water to move in and out as the heating system water expands due to temperature increase or contracts as the water cools. Tanks may be open, closed or diaphragm or bladder type. See Section 6 - Hydronic Piping for suggested best location of expansion tanks and air eliminators.
Check boiler relief valve
1.Inspect the relief valve and lift the lever to verify flow. Before operating any relief valve, ensure that it is piped with its discharge in a safe area to avoid severe scald potential. Read Section 6 - Hydronic Piping before proceeding further.
Following installation, the valve lever must be operated AT LEAST ONCE A YEAR to ensure that waterways are clear. Certain naturally occurring mineral deposits may adhere to the valve, rendering it inoperative. When manually operating the lever, water will discharge and precautions must be taken to avoid contact with hot water and to avoid water damage. Before operating lever, check to see that a discharge line is connected to this valve directing the flow of hot water from the valve to a proper place of disposal. Otherwise severe personal injury may result. If no water flows, valve is inoperative. Shut down the boiler until a new relief valve has been installed.
Safety relief valves should be
AT LEAST ONCE EVERY THREE YEARS, by a licensed plumbing contractor or authorized inspection agency, to ensure that the product has not been affected by corrosive water conditions and to ensure that the valve and discharge line have not been altered or tampered with illegally. Certain naturally occurring conditions may corrode the valve or its components over time, rendering the valve inoperative. Such conditions are not detectable unless the valve and its components are physically removed and inspected. This inspection must only be conducted by a plumbing contractor or authorized inspection agency – not by the owner. Failure to
Installation & Operation Manual
2.After following the warning directions in this manual, if the relief valve weeps or will not seat properly, replace the relief valve. Ensure that the reason for relief valve weeping is the valve and not
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 the Knight Wall Mount Service Manual. Adjust settings if necessary. See Section 1 of the Knight Wall Mount 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 10 -
2.Verify cold fill pressure is correct and that operating pressure does not go too high.
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.
4.When replacing the burner, ensure gasket is in good condition and positioned correctly (FIG.
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