Burner control testing and regulating
Fuel oil filter cleaning or replacement if needed
Cleaning and regulating fuel pump 
Nozzle replacement
Check and adjustment of ignition system
Cleaning - vacuuming boiler or furnace as required
Motor bearings lubricating
Sealing air leaks around boiler doors and flue
Regulating oil burner for maximum efficiency
Oil tank and oil line leak inspection
Electronic combustion analysis/efficiency testing
Documentation dated and signed by the technician with the results of the combustion efficiency and date performed.

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Gas burner service