Maintenance; Routine Maintenance; Blower Assembly; Coils/Drain Pan - AAON M3 Series Installation Operation & Maintenance

Maintenance

Routine Maintenance

Routine maintenance is required to keep the
unit running efficiently and minimize down
time. The following maintenance schedule
should be used.
One week after start-up:
• Check filters for cleanliness. Replace if
necessary.
• Check cycling of fans and valves. Correct
unusual cycling.
• Check for correct damper operation.
• Check blower set screws. Tighten if
necessary.
Monthly:
• Check filters for cleanliness. Replace if
necessary.
• Check drain pans to ensure proper drainage
and clean as necessary.
• Inspect all coils. Clean if dirty or
obstructed in any way.
Seasonal:
• Check operation of heating and cooling
sequences.
• Check for correct damper operation.
• Check fans for wear. Clean if necessary.
Refer to motor manufacturer IOM for re-
lubrication schedule.
• Winterize coils if necessary.
• Inspect and if necessary clean unit interior.
Yearly:
• Clean coils, drain pan and drain line.
• Check electrical connections for tightness.
• Check piping and valves for correct
operation.

Blower Assembly

The M3 Series air handler uses only direct
drive fans. The only bearings that will need
to be lubricated are the ones contained in the
motor. Refer to the motor manufacturer
56
maintenance manual for the correct re-
lubrication schedule
information.
It is important that fans be kept clean to
maintain efficiency and reduce stress on the
unit. To clean the fans first make sure the
power to the unit is turned off. Secure the
fan so it cannot free-wheel. Clean dust and
debris on the fan. Check set screws for
tightness. Rotate the fan by hand and check
for noise and roughness. The fan should
rotate smoothly.
Coils/Drain Pans
Coils must be kept clean to maintain peak
unit efficiency and capacity. Clean filters
will help prevent dirty coils; however, coils
should still be cleaned at least annually by
an HVAC professional.
The coils should be cleaned using steam,
low-pressure water, low-pressure air, or a
non-corrosive coil cleaner.
Condensate drain pans should be inspected
often and cleaned at least annually to
maintain proper drainage and prevent the
spread of disease. Cooling coils are raised
off the drain pan to facilitate cleaning.
The drain and p-traps should also be
checked to prevent clogging. A clogged
and lubricant