1. Inspect fuel system for leaks or damage.
2.  Change fuel filter element and clean strainers; repair leaks, where applicable.
3. Check main flame failure protection, positive fuel shutoff and main flame detection scanner on boiler equipped with spark ignition.
4. Check for proper operational response of burner to thermostat controls.
5. Inspect all gas, steam and water lines, valves, connections for leaks or damage; repair as necessary.
6. Check feedwater system and feedwater makeup control and pump.
7. Check and lubricate burner and blower motors as required.
8. Check operation and condition of safety pressure relief valve.
9. Check combustion controls, combustion blower and damper modulation control.
10. Check all indicator lamps and water/steam pressure gauges.
11. Check electrical panels and wiring to burner, blowers and other components.
12. Clean blower air-intake dampers, if required.
13. Check condition of flue pipe, damper and exhaust stack.
14. Check boiler operation through complete cycle, up to 30 minutes.
15. Check water column sight glass and water level system; clean or replace sight glass, if required.
16. Clean firebox (sweep and vacuum).
17. Clean area around boiler
18. Fill out maintenance checklists and report deficiencies.