AAON M3 Series Owner's manual

M3 Series
Modular Indoor and Outdoor Air Handling Units
Installation, Operation
& Maintenance
QUALIFIED INSTALLER
Improper installation, adjustment,
alteration, service or maintenance
can cause property damage,
personal injury or loss of life. Startup
and service must be performed by a
Factory Trained Service Technician.
A copy of this IOM should be kept
with the unit.
WARNING
If the information in this manual is not
followed exactly, a fire or explosion
may result causing property damage,
personal injury or loss of life.
WARNING
FOR YOUR SAFETY
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
WARNING

2
Table of Contents
Safety .............................................................................................................................................. 7
Unit Orientation............................................................................................................................ 12
Model Number Nomenclature ...................................................................................................... 13
Base Model Feature Description................................................................................................... 14
Supply Fan Module Feature Description...................................................................................... 15
Cooling/Preheat Module Feature Description .............................................................................. 18
Heating Coil Module Description................................................................................................. 21
Blank Module Feature Description............................................................................................... 23
Filter Module Feature Description................................................................................................ 24
Mixing Box/Economizer Module Feature Description................................................................. 25
Discharge Module Feature Description........................................................................................ 27
Control Panel Module Feature Description .................................................................................. 29
Exhaust Fan Module Feature Description..................................................................................... 30
Energy Recovery Module Feature Description............................................................................. 33
Return Fan Module Feature Description....................................................................................... 35
General Description...................................................................................................................... 37
Receiving................................................................................................................................... 37
Storage....................................................................................................................................... 38
Installation..................................................................................................................................... 38
Location/Clearances.................................................................................................................. 38
Rigging...................................................................................................................................... 39
Module Location ....................................................................................................................... 40
Module Assembly ..................................................................................................................... 40
Module Disassembly................................................................................................................. 44
Spring Isolator Adjustment ....................................................................................................... 44
Blower Wheels.......................................................................................................................... 45
Air Adjustment.......................................................................................................................... 45
Condensate Drains..................................................................................................................... 46
Draw-Through P-Trap Example............................................................................................ 48
Blow-Through P-Trap Example............................................................................................ 52
Base Drains ............................................................................................................................... 54
External Control Panel .............................................................................................................. 54
Electrical.................................................................................................................................... 55
Foam Insulated Panel Cutting................................................................................................ 55
Dampers and Actuators............................................................................................................. 56
Duct System .............................................................................................................................. 57
Piping ........................................................................................................................................ 57
Operation....................................................................................................................................... 58
Startup Checklist ....................................................................................................................... 58
Procedures................................................................................................................................. 59
Commissioning.......................................................................................................................... 59
Air Balancing ............................................................................................................................ 59
Water Balancing........................................................................................................................ 60
Controls..................................................................................................................................... 60
Maintenance.................................................................................................................................. 60

3
Routine Maintenance................................................................................................................. 60
Blower Assembly...................................................................................................................... 60
Coils/Drain Pans........................................................................................................................ 60
E-Coated Coil Cleaning.......................................................................................................... 61
Winterizing Coils ...................................................................................................................... 62
Removing Coils......................................................................................................................... 62
Doors/Panels.............................................................................................................................. 63
Outside Opening Door and Panel.............................................................................................. 64
Filters......................................................................................................................................... 64
Replacement Parts..................................................................................................................... 65
M3 Series Startup Form................................................................................................................ 68
Maintenance Log .......................................................................................................................... 71
Literature Change History............................................................................................................. 72
R57350 · Rev. D · 160822

4
Index of Tables and Figures
Tables:
Table 1 - Draw-Through Drain Trap Dimensions ........................................................................ 47
Table 2 - Blow-Through Drain Trap Dimensions......................................................................... 51
Table 3 - Flat Pleated Filters......................................................................................................... 66
Table 4 - Angled Pleated Filters ................................................................................................... 66
Table 5 - Cartridge/Bag Filters..................................................................................................... 66
Figures:
Figure 1 - Unit Orientation ........................................................................................................... 12
Figure 2 - Lockable Handle .......................................................................................................... 38
Figure 3 - Unit Lifting Example ................................................................................................... 39
Figure 4 - Unit Lifting Side View................................................................................................. 39
Figure 5 - Module Location Example........................................................................................... 40
Figure 6 - Moving Module with Pipes.......................................................................................... 41
Figure 7 - Neoprene Gasket.......................................................................................................... 41
Figure 8 - Module Connection...................................................................................................... 41
Figure 9 - Module Connection Example....................................................................................... 41
Figure 10 - Top View of Module Connection .............................................................................. 42
Figure 11 - Aligning Two Modules.............................................................................................. 42
Figure 12 - Aligning the Top of a Unit......................................................................................... 42
Figure 13 - Lifting Lugs and Bolts ............................................................................................... 42
Figure 14 - Come-Along Putting Together Modules.................................................................... 42
Figure 15 - Pulling Sections Together.......................................................................................... 43
Figure 16 - Fastening Sections Together...................................................................................... 43
Figure 17 - Attaching Splice......................................................................................................... 43
Figure 18 - Attaching Corner Rail Cover ..................................................................................... 43
Figure 19 - Attaching Base Splice................................................................................................ 44
Figure 20 - Blower Spring Isolator............................................................................................... 44
Figure 21 - Spring Isolator Adjustment........................................................................................ 45
Figure 22 - Supply Fan Banding................................................................................................... 46
Figure 23 - Draw-Through Drain Trap......................................................................................... 47
Figure 24 –Draw-Through Drain Pan Connection Locations...................................................... 48
Figure 25 - Example Draw-Through AAONEcat32 Rating Sheet ............................................... 49
Figure 26 - Blow-Through Drain Trap ......................................................................................... 51
Figure 27 - Blow-Through Drain Pan Connection Locations....................................................... 52
Figure 28 - Example Blow-Through AAONEcat32 Rating Sheet................................................ 53
Figure 29 - External Control Panel............................................................................................... 55
Figure 30 - Dampers ..................................................................................................................... 56
Figure 31 - Dampers and Actuator................................................................................................ 57
Figure 32 - Independently Controlled Dampers ........................................................................... 57
Figure 33 - Hydronic Coil Connections........................................................................................ 58

5
Figure 34 - Blower Rotation......................................................................................................... 59
Figure 35 - Coil Removal ............................................................................................................. 63
Figure 36 - Access Door/Panel Removal...................................................................................... 64
Figure 37 - Access Door............................................................................................................... 64
Figure 38 - Cartridge/Bag Filter Layout Viewed from Upstream Side........................................ 67

6
AAON®M3 Series Features and Options Introduction
Energy Efficiency
Direct Drive Backward Curved Plenum
Fans
Double Wall Rigid Polyurethane Foam
Injected Panel R-13Construction
Factory Installed AAONAIRE©Energy
Recovery Wheels
Indoor Air Quality
100% Outside Air Configurations
Multiple High Efficiency Filter Options
Double Sloped Stainless Steel Drain Pans
Humidity Control
Modulating Hot Gas Reheat
Safety
Burglar Bars
Installation and Maintenance
Convenience Outlet
Standard Hinged Access Doors
Labeled Electrical Components
Color-Coded Wiring and Wiring
Diagrams
Factory Run Test Report
Clogged Filter Switch
Magnehelic Gauge
Double Pane Viewing Windows
Service Accessible Drain Pan
Slide Out Coil Assembly
System Integration
Shipping Available as Factory
Assembled or Individual Modules
AAON or Customer Provided Controls
Draw-Through or Blow-Through
Configurations
DX and Chilled Water Cooling Options
Electric, Hot Water, Steam, Indirect and
Direct Fired Gas Heating Options
Factory Installed Power Exhaust and
Power Return Fans
Electric Hot Water Preheat
Environmentally Friendly
R-410A Refrigerant
Extended Life
2,500 Hour Salt Spray Tested Interior
and Exterior Protection
6,000 Hour Salt Spray Tested Polymer E-
Coated Coils
Optional 5 Year Parts Warranty
Optional 10 Year Parts Warranty
Stainless Steel Drain Pan

7
Safety
Attention should be paid to the following statements:
NOTE - Notes are intended to clarify the unit installation, operation and maintenance.
CAUTION - Caution statements are given to prevent actions that may result in
equipment damage, property damage, or personal injury.
WARNING - Warning statements are given to prevent actions that could result in
equipment damage, property damage, personal injury or death.
DANGER - Danger statements are given to prevent actions that will result in equipment
damage, property damage, severe personal injury or death.
ELECTRIC SHOCK, FIRE OR
EXPLOSION HAZARD
Failure to follow safety warnings
exactly could result in dangerous
operation, serious injury, death or
property damage.
Improper servicing could result in
dangerous operation, serious injury,
death or property damage.
Before servicing, disconnect all
electrical power to the unit. More
than one disconnect may be
provided.
When servicing controls, label all
wires prior to disconnecting.
Reconnect wires correctly.
Verify proper operation after
servicing. Secure all doors with
key-lock or nut and bolt.
WARNING
Electric shock hazard. Before
servicing, disconnect all electrical
power to the unit, including remote
disconnects, to avoid shock hazard
or injury from rotating parts. Follow
proper Lockout-Tagout procedures.
WARNING
FIRE, EXPLOSION OR CARBON
MONOXIDE POISONING HAZARD
Failure to replace proper controls
could result in fire, explosion or
carbon monoxide poisoning. Failure
to follow safety warnings exactly
could result in serious injury, death or
property damage. Do not store or use
gasoline or other flammable vapors
and liquids in the vicinity of this
appliance.
WARNING

8
VARIABLE FREQUENCY DRIVES
Do not leave VFDs unattended in
hand mode or manual bypass.
Damage to personnel or equipment
can occur if left unattended. When in
hand mode or manual bypass mode
VFDs will not respond to controls or
alarms.
WARNING
GROUNDING REQUIRED
All field installed wiring must be
completed by qualified personnel.
Field installed wiring must comply
with NEC/CEC, local and state
electrical code requirements. Failure
to follow code requirements could
result in serious injury or death.
Provide proper unit ground in
accordance with these code
requirements.
WARNING
During installation, testing, servicing
and troubleshooting of the equipment
it may be necessary to work with live
electrical components. Only a
qualified licensed electrician or
individual properly trained in handling
live electrical components shall
perform these tasks.
Standard NFPA-70E, an OSHA
regulation requiring an Arc Flash
Boundary to be field established and
marked for identification of where
appropriate Personal Protective
Equipment (PPE) be worn, should be
followed.
WARNING
UNIT HANDLING
To prevent injury or death lifting
equipment capacity shall exceed unit
weight by an adequate safety factor.
Always test-lift unit not more than 24
inches high to verify proper center of
gravity lift point to avoid unit damage,
injury or death.
WARNING
ROTATING COMPONENTS
Unit contains fans with moving parts
that can cause serious injury. Do not
open door containing fans until the
power to the unit has been
disconnected and fan wheel has
stopped rotating.
WARNING
Electric motor over-current protection
and overload protection may be a
function of the Variable Frequency
Drive to which the motors are wired.
Never defeat the VFD motor overload
feature. The overload ampere setting
must not exceed 115% of the electric
motors FLA rating as shown on the
motor nameplate.
CAUTION
Failure to properly drain and vent
coils when not in use during freezing
temperature may result in coil and
equipment damage.
CAUTION

9
Do not clean DX refrigerant coils with
hot water or steam. The use of hot
water or steam on refrigerant coils
will cause high pressure inside the
coil tubing and damage to the coil.
WATER PRESSURE
Prior to connection of condensing
water supply, verify water pressure is
less than maximum pressure shown
on unit nameplate. To prevent injury
or death due to instantaneous
release of high pressure water, relief
valves should be field supplied on
system water piping.
To prevent damage to the unit, do not
use acidic chemical coil cleaners. Do
not use alkaline chemical coil
cleaners with a pH value greater than
8.5, after mixing, without first using
an aluminum corrosion inhibitor in the
cleaning solution.
CAUTION
WARNING
CAUTION
Do not use oxygen, acetylene or air
in place of refrigerant and dry
nitrogen for leak testing. A violent
explosion may result causing injury or
death.
WARNING
Always use a pressure regulator,
valves and gauges to control
incoming pressures when pressure
testing a system. Excessive pressure
may cause line ruptures, equipment
damage or an explosion which may
result in injury or death.
WARNING
Do not work in a closed area where
refrigerant or nitrogen gases may be
leaking. A sufficient quantity of
vapors may be present and cause
injury or death.
WARNING
Rotation must be checked on all
MOTORS AND COMPRESSORS of
3 phase units at startup by a qualified
service technician. Scroll
compressors are directional and can
be damaged if rotated in the wrong
direction. Compressor rotation must
be checked using suction and
discharge gauges. Fan motor rotation
should be checked for proper
operation. Alterations should only be
made at the unit power connection
CAUTION
Do not weld or cut foam panel with
plasma cutters or a cutting torch –
When burnt the foam produces
dangerous fumes.
WARNING

10
Some chemical coil cleaning
compounds are caustic or toxic. Use
these substances only in accordance
with the manufacturer’s usage
instructions. Failure to follow
instructions may result in equipment
damage, injury or death.
WARNING
Door compartments containing
hazardous voltage or rotating parts
are equipped with door latches to
allow locks. Door latch are shipped
with nut and bolts requiring tooled
access. If you do not replace the
shipping hardware with a pad lock
always re-install the nut & bolt after
closing the door.
CAUTION
Check the shipping section weights
on the Bill of Lading to be sure they
can be lifted safely. Rigging should
be adjusted so that all sections are
lifted level.
WARNING
Do not enter or reach into a fan
cabinet while the fan is still turning.
WARNING
Never attempt to open an access
door or remove a panel while the unit
is running. Pressure in the unit can
cause excessive force against the
panel.
WARNING
Never pressurize equipment over 8”
w.c –Equipment and property
damage, personal injury or loss of life
could result.
WARNING
Ensure that sufficient dampers will be
open to provide air path before fan is
allowed to run.
WARNING
Risk of injury from hot parts –
Disconnect all power, close all
isolation valves and allow equipment
to cool before servicing equipment
with hot water and steam heating
coils. Hot water will circulated even
after the power is off.
WARNING
PVC (Polyvinyl Chloride) and CPVC
(Chlorinated Polyvinyl Chloride) are
vulnerable to attack by certain
chemicals. Polyolester (POE) oils
used with R-410A and other
refrigerants, even in trace amounts,
in a PVC or CPVC piping system will
result in stress cracking of the piping
and fittings and complete piping
system failure.
CAUTION