AAON LN Series Owner's manual

LN Series
Chillers and Outdoor Mechanical Rooms
Installation, Operation,
& Maintenance
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings
exactly could result in serious injury,
death or property damage.
Be sure to read and understand the
installation, operation and service
instructions in this manual.
Improper installation, adjustment,
alteration, service or maintenance can
cause serious injury, death or property
damage.
A copy of this IOM should be kept with
the unit.
Do not store gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance.
Do not touch any electrical switch;
do not use any phone in your
building.
Leave the building immediately.
Immediately call you gas supplier
from a phone remote from the
building. Follow the gas supplier’s
instructions.
If you cannot reach your gas
supplier call the fire department.
Startup and service must be
performed by a Factory Trained
Service Technician.
WARNING
WARNING

Table of Contents
Codes and Ordinances............................................................................................................... 14
Receiving Unit........................................................................................................................... 14
Storage....................................................................................................................................... 15
Chiller........................................................................................................................................ 15
Wiring Diagrams....................................................................................................................... 16
General Maintenance................................................................................................................. 16
Chiller Primary Pumping .......................................................................................................... 16
Automatic Air Vent................................................................................................................... 17
Dual Pumps ............................................................................................................................... 17
Pressure Gauges and Thermometers ......................................................................................... 17
Pipe Insulation........................................................................................................................... 17
Chiller Placement...................................................................................................................... 18
Curb and Steel Mount Installation ............................................................................................ 18
Lifting and Handling................................................................................................................. 19
Water Connection...................................................................................................................... 21
Mounting Isolation.................................................................................................................... 21
Access Doors............................................................................................................................. 21
End Flashing Installation........................................................................................................... 21
Low Ambient Operation............................................................................................................ 22
Electrical.................................................................................................................................... 22
Variable Speed Compressors .................................................................................................... 24
Axial Flow Condenser Fans...................................................................................................... 26
General ...................................................................................................................................... 29
Compressors.............................................................................................................................. 29
Refrigerant Suction Line Filter ................................................................................................. 29
Suction Filter Removal Instructions.......................................................................................... 29
Adjusting Refrigerant Charge ................................................................................................... 30
Lubrication ................................................................................................................................ 33
Air-Cooled Condenser............................................................................................................... 33
Brazed Plate Heat Exchanger Cleaning .................................................................................... 33
E-Coated Coil Cleaning ............................................................................................................ 33
Microchannel Coil Cleaning ..................................................................................................... 36
Service....................................................................................................................................... 38
Replacement Parts..................................................................................................................... 38
AAON Technical Support......................................................................................................... 38
Automatic Air Vent Valves....................................................................................................... 39
Pumps - Installation and Operating Instructions....................................................................... 41
Pump Piping - General.............................................................................................................. 42
Pump Operation......................................................................................................................... 43
General Care.............................................................................................................................. 44
Dual Pump Specific Information............................................................................................... 46
Suction Guides .......................................................................................................................... 51
Flo-Trex Combination Valve .................................................................................................... 52

3
Index of Tables and Figures
Tables:
Table 1 - Service Clearances......................................................................................................... 18
Table 2 - Mounting Dimensions................................................................................................... 19
Table 3 - Nameplate Voltage Markings........................................................................................ 22
Table 4- Tandem Circuited Variable Speed Compressor VFD Frequency Range....................... 24
Table 5 - Return/Exhaust Fan Pin Location.................................................................................. 27
Table 6 - Return/Exhaust Fan Pin Location.................................................................................. 27
Table 7 - Fan Assembly Bushing Torque Specifications.............................................................. 28
Table 8 - Acceptable Refrigeration Circuit Values....................................................................... 31
Table 9 - R-410A Refrigerant Temperature-Pressure Chart......................................................... 32
Figures:
Figure 1 - LN Base........................................................................................................................ 18
Figure 2 - Curb Mounting with Dimensions................................................................................. 19
Figure 3 - Steel Mounting Rail with Dimensions......................................................................... 19
Figure 4 - Lifting Points................................................................................................................ 19
Figure 5 - Lifting Detail of a 45-60 ton Unit................................................................................ 20
Figure 6 - Lifting Detail of a 75-140 ton Unit.............................................................................. 20
Figure 7 - Factory Supplied End Flashings................................................................................... 21
Figure 8 - Front View of Utility Entry and Power Switch from Control Compartment............... 23
Figure 9 - Fan with the HUB on the top and RET on the bottom................................................. 26
Figure 10 - Bushing Mount Location............................................................................................ 26
Figure 11 - RET with Pin in Groove 4.......................................................................................... 26
Figure 12 - Fan HUB and RET Castings...................................................................................... 27
Figure 13 - Pitch Insert ................................................................................................................. 28
V28980 · Rev. B · 190515

4
AAON®LN Series Features and Options Introduction
Energy Efficiency
High Efficiency Air-Cooled
Microchannel Condenser
Staged or Tandem VFD Controlled
Variable Speed R-410A Scroll
Compressors
Two Inch Double Wall Rigid
Polyurethane Foam Panel Construction
VFD Controlled Pumping Package
Glycol Chillers
Constant or Variable Flow Factory
Installed Pumping System
VFD Controlled Condenser Fan Head
Pressure Control
ECM Low Sound Condenser Fan Head
Pressure Control
Factory Installed EXVs
Outdoor Mechanical Room
Lighted Service Compartment
Shell and Tube or Brazed Plate Heat
Evaporators
Factory Engineered Primary Pumping
Package
Safety
Phase and Brownout Protection
Environmentally Friendly
R-410A Refrigerant
Installation and Maintenance
Run Test Report and Installation Manuals
Included in Controls Compartment
Color Coded Wiring Diagrams
Sight Glass
Compressors include Rubber Isolation
Mounts
Vestibule Electric Heating in Service
Compartment
Compressor Isolation Valves
Convenience Outlet
Non-fused Disconnect
Thermometers & Pressure Gauges
System Integration
Complete System with AAON Chilled
Water Air Handling Units
Single Point Power
Glycol Chillers
Grooved End Water Piping Connections
Constant or Variable Flow Factory
Installed Pumping System
BMS Connectivity
Extended Life
2,500 Hour Salt Spray Tested Exterior
Corrosion Paint
Optional 5 Year Non-Prorated
Compressor Warranty
Polymer E-Coated Condenser Coils
Exterior Cabinet Paint Exceeds 2,500
Salt Spray Test
Condenser Coil Guards

5
Safety
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 furnace.
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
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.
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
WHAT TO DO IF YOU SMELL GAS
Do not try to turn on unit.
Shut off main gas supply.
Do not touch any electric switch.
Do not use any phone in the
building.
Never test for gas leaks with an
open flame.
Use a gas detection soap solution
and check all gas connections and
shut off valves.
CAUTION

6
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.
Electric shock hazard. Before
servicing, shut off all electrical power
to the unit, including remote
disconnects, to avoid shock hazard or
injury from rotating parts. Follow
proper Lockout-Tagout procedures.
WARNING
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
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
GROUNDING REQUIRED
All field installed wiring must be
completed by qualified personnel.
Field installed wiringmust 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
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

7
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
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
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
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 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
To prevent damage to the unit, do not
use acidic chemical coil cleaners. Use
alkaline chemical coil cleaners with a
pH value of 5-9, after mixing, without
first using an aluminum corrosion
inhibitor in the cleaning solution.
CAUTION

8
1. Startup and service must be performed by
a Factory Trained Service Technician
2. The unit is for outdoor use only. See
General Information section for more
information.
3. Every unit has a unique equipment
nameplate with electrical, operational,
and unit clearance specifications. Always
refer to the unit nameplate for specific
ratings unique to the model you have
purchased.
4. READ THE ENTIRE INSTALLATION,
OPERATION AND MAINTENANCE
MANUAL. OTHER IMPORTANT
SAFETY PRECAUTIONS ARE
PROVIDED THROUGHOUT THIS
MANUAL.
5. Keep this manual and all literature
safeguarded near or on the unit.
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
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.
CAUTION
Polyolester (POE) and Polyvinylether
(PVE) oils are two types of lubricants
used in hydrofluorocarbon (HFC)
refrigeration systems. Refer to the
compressor label for the proper
compressor lubricant type.
CAUTION
COMPRESSOR CYCLING
3 MINUTE MINIMUM OFF TIME
To prevent motor overheating
compressors must cycle off for a
minimum of 3 minutes.
3 MINUTE MINIMUM ON TIME
To maintain the proper oil level
compressors must cycle on for a
minimum of 3 minutes.
The cycle rate must not exceed 6
starts per hour.
WARNING

9
LN Series Feature String Nomenclature
Model Options
:
Unit Feature Options
GEN
MJREV
SIZE
SERIES
MNREV
VLT
A1 A2 A3 A4 A5
B1 B2 B3 B4
1 2
3A 3B 3C 3D
4A 4B 4C 4D
5A 5B 5C 5D
6 7
8A 8B 8C
9
10A 10B 10C 10D
LNA–140 –C–A–3–FAC0E–0000: A0–0 0 0 0 –0 0 0 0 –0 0 0 0 –0 0 –0 0 0 –0 –0 E 0 0 –
0 0 0 0 0 –0 A 0 0 0 –0 0 0 0 0 –0 0 0 0 0 0 –0 0 0 0 0 –0 0 0 B
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
26A 26B 26C 26D 26E 26F
27 28 29 30 31
32 33 34 35
MODEL OPTIONS
SERIES AND GENERATION
LN
MAJOR REVISION
A
UNIT SIZE
045 = 45 ton Capacity
055 = 55 ton Capacity
060 = 60 ton Capacity
075 = 75 ton Capacity
095 = 95 ton Capacity
105 = 105 ton Capacity
120 = 120 ton Capacity
140 = 140 ton Capacity
SERIES
A = 45-60 ton units
B = 75 ton unit
C = 95-140 ton units
MINOR REVISION
A
VOLTAGE
2 = 230V/3Φ/60Hz
3 = 460V/3Φ/60Hz
4 = 575V/3Φ/60Hz
8 = 208V/3Φ/60Hz
A1: COMPRESSOR STYLE
F = R-410A Tandem VFD Compatible Scroll
Compressor
A2: CONDENSER STYLE
A = Air-Cooled Microchannel Condenser
A3: EVAPORATOR CONFIGURATION
A = Standard Brazed Plate Constant Flow
B = Oversized Brazed Plate Constant Flow
C = Standard Shell & Tube Constant Flow
D = Oversized Shell & Tube Constant Flow
A4: COATING
0 = Standard
E = Polymer E-Coated Condenser Coil
A5: STAGING
0 = Staged Compressors
E = All Circuits with Variable Capacity Compressors
- 2 Circuits
G = Half Circuits with Variable Capacity
Compressors - 2 Circuits
B1: BLANK
0 = Standard
B2: BLANK
0 = Standard
B3: BLANK
0 = Standard
B4: BLANK
0 = Standard
UNIT FEATURE OPTIONS
1: UNIT ORIENTATION
A = Standard Access Left Water Connections
B = Standard Access Right Water Connections
C = Standard Access Bottom Water Connections
2: PUMPING STYLE
0 = No Pumps
B = Constant Flow Primary Pumping System - Large
Pipe Size
D = Variable Flow Primary Pumping System - Large
Pipe Size

10
LN Series Feature String Nomenclature
Model Options
:
Unit Feature Options
GEN
MJREV
SIZE
SERIES
MNREV
VLT
A1 A2 A3 A4 A5
B1 B2 B3 B4
1 2
3A 3B 3C 3D
4A 4B 4C 4D
5A 5B 5C 5D
6 7
8A 8B 8C
9
10A 10B 10C 10D
LN A –140 –C –A –3 –F A C 0 E –0 0 0 0 : A 0 –0000 –0 0 0 0 –0 0 0 0 –0 0 –0 0 0 –0 –0 E 0 0 –
0 0 0 0 0 –0 A 0 0 0 –0 0 0 0 0 –0 0 0 0 0 0 –0 0 0 0 0 –0 0 0 B
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
26A 26B 26C 26D 26E 26F
27 28 29 30 31
32 33 34 35
3A: BUILDING PUMP CONFIGURATION
0 = No Building Pumps
A = 1 Pump + High Eff Motor
B = 1 Dual Pump + High Eff Motors
D = 1 Pump + VFD + High Eff Motor
E = 1 Dual Pump + 2 VFD's + High Eff Motors
K = 1 Pump + Field Installed VFD + High Eff Motor
L = 1 Dual Pump + 2 Field Installed VFD's + High
Eff Motors
3B: BUILDING PUMP SERIES AND RPM
0 = No Building Pumps
A = 4360 (1,170 nominal rpm)
B = 4360 (1,760 nominal rpm)
C = 4360 (3,520 nominal rpm)
D = 4380 (1,170 nominal rpm)
E = 4380 (1,760 nominal rpm)
F = 4380 (3,520 nominal rpm)
K = 4382 (1,170 nominal rpm)
L = 4382 (1,760 nominal rpm)
M = 4382 (3,520 nominal rpm)
3C: PUMP SIZE
0 = No Building Pumps
A = 1.5B
B = 2B
C = 2D
D = 3D
E = 1.5x1.5x6
F = 2x2x6
G = 3x3x6
H = 4x4x6
J = 6x6x6
K = 1.5x1.5x8
L = 2x2x8
M = 3x3x8
N = 4x4x8
P= 5x5x8
Q = 6x6x8
R = 8x8x8
S = 2x2x10
T = 3x3x10
U = 4x4x10
V = 6x6x10
W = 8x8x10
Y = 4x4x11.5
Z = 5x5x11.5
1 = 6x6x11.5
2 = 8x8x11.5
3 = 4x4x13
4 = 6x6x13
5 = 8x8x13