A.O. Smith 3400 - Manual (Page 74)

74
INSPECT BOILER AREA
1. Verify that boiler area is free of any combustible materials,
gasoline and other flammable vapors and liquids.
2. Verify that air intake area is free of any of the contaminants.
If any of these are present in the boiler intake air vicinity,
they must be removed. If they cannot be removed, reinstall
the air and vent lines per this manual.
Inspect boiler interior:
1. Remove the front access cover and inspect the interior of
the boiler.
2. Vacuum any sediment from inside the boiler and components.
Remove any obstructions.
GENERAL MAINTENANCE
This is a pre-mix burner system. The flame is not supposed to be
directly on the burner. The flame should be just above the burner
deck approximately 1/8” and blue in color, see Figure 74.
FIGURE 74. BURNER FLAMES
Visually check flame characteristics through the view port located
on the top head of the boiler. Figure 74 shows the normal flame
condition.
These boilers are designed to give many years of efficient and
satisfactory service when properly operated and maintained.
To assure continued good performance, the following
recommendations are made.
The area around the unit should be kept clean and free from lint
and debris. Sweeping the floor around the boiler should be done
carefully. This will reduce the dust and dirt which may enter the
burner and heat exchanger, causing improper combustion and
sooting.
MAIN BURNER
Check main burner every three months for proper flame
characteristics. The main burner should display the following
characteristics:
• Provide complete combustion of gas.
• Cause rapid ignition and carry over of flame across entire burner.
• Give reasonably quiet operation during initial ignition, operation
and extinction.
• Cause no excessive lifting of flame from burner ports.
MAINTENANCE PROCEDURES
MAINTENANCE SCHEDULES
Yearly procedures for Qualified Service Technician:
• Check for reported problems.
• Check the interior; clean and vacuum if needed.
• Clean the condensate trap and fill with fresh water.
• Check for water/gas/flue/ condensate leaks.
• Ensure flue and air lines in good condition and sealed
tight
• Check system water pressure/system piping/expansion
tank
• Check control settings.
• Check spark igniter and flame sensors. Clear and clean
any deposits.
• Check wiring and connections.
• Perform start-up checkout and performance verification.
• Flame inspection (stable, uniform)
• Flame signal (at least 10 microamps at high fire)
• Clean the heat exchanger if flue temperature is more
than 54°F (30°C) above return water temperature.
• Test low water flow conditions.
• Clean the heat exchanger.
• Remove and clean burner using compressed air.
Maintenance by Owner:
Daily:
• Check boiler area .
• Check pressure/temperature gauge.
Monthly:
• Check vent piping.
• Check air intake piping (Direct Vent).
• Check air and vent termination screens.
• Check relief valve.
• Check condensate drain system.
• Check automatic air vents .
Every 6 months:
• Check boiler piping (gas and water) for leaks.
• Check and operate the pressure relief valve.
End of season months:
• Shut the boiler down.
The maintenance of the boiler must be performed to assure
maximum boiler efficiency and reliability. Failure to service and
maintain the boiler and system could result in equipment failure.
Make sure to turn off power to the boiler before any service
operation on the boiler except as noted otherwise in this
instruction manual. Failure to turn off electrical power could result
in electrical shock, causing severe personal injury or death.