A.O. Smith Copper Boiler DW-840

Ensure the circulating pump is properly sized for the application

Check water hardness and system pressure drop

Verify temperature rise across the boiler

Oil the three oil cups (2 on the motor, 1 on the pump) as instructed on the oil tube

Add 2 or 3 teaspoonfuls of No. 20 non-detergent motor oil in bearing oil cups

Add 10 or 12 drops of No. 20 non-detergent motor oil in motor oil cups

Shut off all gas and electric to unit

Disconnect union assembly and pilot line connection at main burner

Slide burner tray out of cabinet

Check that burner venturi and ports are free of foreign matter

Clean burners with bristle brush and/or vacuum cleaner 3/4"

Reinstallation and Final Checks

Inspect all safety devices including low water cutoffs for proper operation

Low Water Cutoff Device Maintenance

Flush the low water cutoff device of the float type

Attach a pressure gauge or a manometer to the gauge port and check for correct manifold pressure.

Is the pressure within the limit indicated on the rating plate?

Ensure other gas consuming appliances are turned off.

Enter the time in seconds to burn one cubic foot of gas (T).

Enter the gas heating value in Btu per cubic foot of gas (H).

Calculate the actual boiler input per hour (Btuh) using the formula (3600/T)xH.

Main Burner Flame Characteristics Check

Check for complete combustion of gas

Check for rapid ignition and flame carryover across entire burner

Check for reasonably quiet operation during initial ignition, operation, and extinction

Check for no excessive lifting of flame from burner ports

Is there any accumulation of lint or foreign material restricting air openings?

Clear any lint or foreign material from air openings if present