Aaon LF-004 Installation Manual

Page 1
LF Series
Air-Cooled Condenser Chillers
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.
FOR YOUR SAFETY
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.
QUALIFIED INSTALLER
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a Factory Trained Service Technician. A copy of this IOM should be kept with the unit.
Installation, Operation,
& Maintenance
Page 2
Page 3
Table of Contents
AAON LF Series Features and Options Introduction ..................................................................... 6
Safety .............................................................................................................................................. 7
LF Series Feature String Nomenclature .......................................................................................... 9
General Description ...................................................................................................................... 14
Receiving Unit ........................................................................................................................... 14
Chiller ........................................................................................................................................ 15
Wiring Diagrams ....................................................................................................................... 16
General Maintenance ................................................................................................................. 16
Primary Pumping Package ........................................................................................................ 16
Glycol ........................................................................................................................................ 17
Compression Tank ..................................................................................................................... 17
Pressure Relief Valve ................................................................................................................ 17
Manual and Automatic Air Vent ............................................................................................... 17
Dual Pumps ............................................................................................................................... 17
Differential Pressure Gauge and Thermometers ....................................................................... 17
Pipe Insulation ........................................................................................................................... 18
Installation..................................................................................................................................... 18
Forklifting the Unit (4-17 and 22-24 ton) ................................................................................. 18
Lifting the Unit .......................................................................................................................... 18
Locating the Unit ....................................................................................................................... 20
Water Connection ...................................................................................................................... 20
Mounting Isolation .................................................................................................................... 21
Access Doors ............................................................................................................................. 21
Low Ambient Operation ............................................................................................................ 21
LAC Valve ............................................................................................................................. 22
Condenser Flooding ............................................................................................................... 22
Electrical .................................................................................................................................... 23
Startup ........................................................................................................................................... 24
Maintenance .................................................................................................................................. 25
General ...................................................................................................................................... 25
Compressors .............................................................................................................................. 25
Refrigerant Filter Driers ............................................................................................................ 25
Adjusting Refrigerant Charge ................................................................................................... 25
Lubrication ................................................................................................................................ 27
Service ....................................................................................................................................... 27
Warranties ................................................................................................................................. 28
Condenser Tube Inspection ....................................................................................................... 28
Pump Operation ......................................................................................................................... 28
Access Doors ............................................................................................................................. 28
Pump Bearings - Lubrication .................................................................................................... 28
Air Inlet ..................................................................................................................................... 28
Propeller Fans and Motors ........................................................................................................ 28
Recommended Annual Inspection ............................................................................................ 29
Mechanical Cleaning ................................................................................................................. 29
Air-Cooled Condenser ............................................................................................................... 29
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Page 4
E-Coated Coil Cleaning ............................................................................................................ 29
Recommended Coil Cleaner .................................................................................................. 30
Recommended Chloride Remover ......................................................................................... 30
Microchannel Coil Cleaning ..................................................................................................... 30
Replacement Parts ..................................................................................................................... 32
AAON - Longview Warranty, Service, and Parts Department ................................................. 32
Appendix - Water Piping Component Information ...................................................................... 33
Water Pressure Relief Valve ..................................................................................................... 33
Automatic Air Vent Valves ....................................................................................................... 33
Pumps: Installation and Operating Instructions ........................................................................ 34
Dual Pump Specific Information ............................................................................................... 39
Valve Operation ........................................................................................................................ 39
Suction Guides .......................................................................................................................... 44
Flo-Trex Combination Valve .................................................................................................... 45
LF Series Startup Form ................................................................................................................. 50
Maintenance Log .......................................................................................................................... 53
Literature Change History............................................................................................................. 54
V45070 · Rev. A · 150716
(ACP J00425)
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Index of Tables and Figures
Tables:
Table 1 - 4-7 & 9 ton Service Clearances ..................................................................................... 20
Table 2 - 8 & 10-13 ton Service Clearances ................................................................................. 20
Table 3 - 14-17 & 22-24 ton Service Clearances .......................................................................... 20
Table 4 - 21 & 26-55 ton Service Clearances ............................................................................... 20
Table 5 - Condenser Flooding....................................................................................................... 22
Table 6 - Max Filter Drier Pressure Drops ................................................................................... 25
Table 7 - Acceptable Refrigeration Circuit Values ....................................................................... 26
Table 8 - R-410A Refrigerant Temperature-Pressure Chart ......................................................... 27
Figures:
Figure 1 - Pressure Relief Valve ................................................................................................... 17
Figure 2 - Forklifting an LF Series A, B and C Cabinet, 4-17 and 22-24 tons ............................. 18
Figure 3 - Lifting Details of a 4-17 and 22-24 ton Standard Unit ................................................ 19
Figure 4 - Lifting Details of a 21 and 26-55 ton Standard Unit .................................................... 19
Figure 5 - Piping Schematic of Example System using the LAC Valve ...................................... 22
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Page 6

AAON LF Series Features and Options Introduction

Energy Efficiency
Staged or 10-100% Variable Capacity R-
410A Scroll Compressors
High Efficiency Air-Cooled
Microchannel Condenser Coils
VFD Controlled Pumping Packages
VFD Controlled or ECM Driven
Condenser Fans
Waterside Economizers
Factory Installed EXVs
Outdoor Mechanical Room
Chilled Water Applications up to 55 tons
Isolated Controls and Compressor
Compartment
Isolated Evaporator and Pumping
Package Compartment
Factory Engineered Primary Pumping
Packages
Brazed Plate or Shell and Tube
Evaporators
Safety
Phase and Brownout Protection
Single Point Non-Fused Disconnect
Power Switch
Waterside Thermometer and Pressure
Gauge
Installation and Maintenance
Double Wall Rigid Polyurethane Foam
Injected Panel Construction
Access Doors with Full Length Stainless
Steel Piano Hinges
Molded Lockable Handles
Factory Installed Convenience Outlet
Service Vestibule Heating
Controls Diagnostics
Touchscreen Computer Controls
Interface
Liquid Line Sight Glass
Compressor Isolation Valves
Color-Coded Wiring Diagrams
System Integration
Complete System with AAON Chilled
Water Air Handling Units
BMS Connectivity
Grooved End Water Piping Connections
Custom Order Paint Options
Environmentally Friendly
R-410A Refrigerant
Extended Life
5 Year Compressor Warranty
Condenser Coil Guards
2,500 Hour Salt Spray Tested Exterior
Corrosion Protection
6,000 Hour Salt Spray Tested Polymer
E-Coated Condenser Coils
6
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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
Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or
Improper servicing could result in dangerous operation, serious injury,
When servicing controls, label all wires prior to disconnecting.
Verify proper operation after servicing. Secure all doors with
FIRE, EXPLOSION OR CARBON
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. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.

Safety

EXPLOSION HAZARD
MONOXIDE POISONING HAZARD
property damage.
death, or property damage.
Reconnect wires correctly.
key-lock or nut and bolt.
7
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8
To prevent motor overheating compressors must cycle off for a
To maintain the proper oil level compressors must cycle on for a
The cycle rate must not exceed 6 starts per hour.
WARNING
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.
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
COMPRESSOR CYCLING
5 MINUTE MINIMUM OFF TIME
minimum of 5 minutes.
2 MINUTE MINIMUM ON TIME
minimum of 2 minutes.
VARIABLE FREQUENCY DRIVES
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. READ THE ENTIRE INSTALLATION,
OPERATION AND MAINTENANCE MANUAL. OTHER IMPORTANT SAFETY PRECAUTIONS ARE PROVIDED THROUGHOUT THIS MANUAL.
4. Keep this manual and all literature
safeguarded near or on the unit.
Page 9

LF 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
LF A -
031
- D - 0 - 3 - D A C 0
E - 0 0 0
0
: C 0 - 0 0 0 0 - 0 0 0 0 - 0 0 0 0 - 0 0 - 0 0 0
0 - 0 E 0 0 - 0 0 C 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 D
B
9
10A
10B
10C
10D
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
LF Series Feature String Nomenclature
MODEL OPTIONS
SERIES AND GENERATION
LF
MAJOR REVISION
A
UNIT SIZE
004 = 4 ton Capacity 005 = 5 ton Capacity 007 = 7 ton Capacity 008 = 8 ton Capacity 009 = 9 ton Capacity 010 = 10 ton Capacity 011 = 11 ton Capacity 013 = 13 ton Capacity 014 = 14 ton Capacity 015 = 15 ton Capacity 017 = 17 ton Capacity 021 = 21 ton Capacity 022 = 22 ton Capacity 024 = 24 ton Capacity 026 = 26 ton Capacity 031 = 31 ton Capacity 042 = 42 ton Capacity 048 = 48 ton Capacity 055 = 55 ton Capacity
SERIES
A = 4-7 and 9 ton units B = 8 and 10-13 ton unit C = 14-17 and 22-24 ton units D = 21 and 26-55 ton units
MINOR REVISION
0
VOLTAGE
2 = 230V/3Φ/60Hz 3 = 460V/3Φ/60Hz 4 = 575V/3Φ/60Hz 8 = 208V/3Φ/60Hz
A1: COMPRESSOR STYLE
A = R-410A Scroll Compressors D = R-410A Variable Capacity Scroll Compressors E = R-410A Tandem Scroll Compressors G = R-410A Tandem Variable Capacity Scroll
Compressors
A2: CONDENSER STYLE
A = Air-Cooled Microchannel Condenser
A3: EVAPORATOR CONFIGURATION
A = Brazed Plate B = Oversized Brazed Plate
A4: Coating
0 = Standard E = Polymer E-Coated Condenser Coil
A5: Staging
0 = Staged On/Off Compressors E = All Variable Capacity Compressors G = Half Variable Capacity Compressors
B1: Blank
0 = Standard
B2: Blank
0 = Standard
B3: Blank
0 = Standard
B4: Blank
0 = Standard
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LF 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
LF A -
031 - D - 0 - 3 - D A C 0 E - 0 0 0 0 :
C 0 - 0 0
0
0
- 0 0 0 0 - 0 0 0 0 - 0 0 - 0 0 0
0 - 0 E 0 0 - 0 0 C 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 D
B
9
10A
10B
10C
10D
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
10
UNIT FEATURE OPTIONS
1: Unit Orientation
0 = Standard Access End Water Connections
2: Pumping Style
B = Const. Primary Pumping System Large Pipe Size D = Var. Primary Pumping System Large Pipe Size J = No Pumping Package - Piping to Connections at
Wall Cutouts
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
3B: Building Pump Series and RPM
0 = No Building Pumps A = 4360 (1,200 nominal rpm) B = 4360 (1,800 nominal rpm) C = 4360 (3,600 nominal rpm) D = 4380 (1,200 nominal rpm) E = 4380 (1,800 nominal rpm) F = 4380 (3,600 nominal rpm) K = 4382 (1,200 nominal rpm) L = 4382 (1,800 nominal rpm) M = 4382 (3,600 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
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LF 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
LF A -
031 - D - 0 - 3 - D A C 0 E - 0 0 0 0 : C 0 - 0 0 0
0 - 0 0 0 0 - 0 0 0 0 - 0 0 - 0 0
0
0 - 0
E
0 0 - 0 0 C 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 D
B
9
10A
10B
10C
10D
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
3D: Building Pump Motor Size
0 = No Building Pumps A = 0.5 hp B = 0.75 hp C = 1 hp D = 1.5 hp E = 2 hp F = 3 hp G = 5 hp H = 7.5 hp J = 10 hp K = 15 hp L = 20 hp M = 25 hp N = 30 hp P = 40 hp Q = 50 hp R = 60 hp S = 75 hp
4A: Blank
0 = Standard
4B: Blank
0 = Standard
4C: Blank
0 = Standard
4D: Blank
0 = Standard
5A: Blank
0 = Standard
5B: Blank
0 = Standard
5C: Blank
0 = Standard
5D: Blank
0 = Standard
6: Refrigeration Options
0 = None A = Hot Gas Bypass Non-Variable Capacity
Compressor Circuits
B = Hot Gas Bypass - All Circuits
7: Refrigeration Accessories
0 = Standard A = Sight Glass B = Compressor Isolation Valves C = Option A + B D = 1 Circuit Low Ambient E = Option A + D F = Option B + D G = Option A + B + D H = 2 Circuits Low Ambient J = Option A + H K = Option B + H L = Option A + B + H
8A: Unit Disconnect Type
0 = Standard Single Point Power Block A = Single Point Power Non-fused Disconnect
8B: Disconnect 1 Size
0 = Power Block N = 100 amps R = 150 amps V = 250 amps Z = 400 amps
8C: Blank
0 = Standard
9: Accessories
0 = None B = Phase & Brown Out Protection E = Compressor Sound Blanket M = Option B + E
10A: Unit Control Sequence
0 = Standard AAON Controls
10B: Unit Control Supplier
E = MCS Controls
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LF 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
LF A -
031 - D - 0 - 3 - D A C 0 E - 0 0 0 0 : C 0 - 0 0 0 0 - 0 0 0 0 - 0 0 0 0 - 0 0 - 0 0 0
0 - 0
E
0 0 - 0 0 C 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 D
B
9
10A
10B
10C
10D
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
12
10C: Control Supplier Options
0 = None C = Modem
10D: BMS Connection & Diagnostics
0 = None A = BACnet IP B = BACnet MSTP C = Modbus IP D = Modbus RTU E = LonTalk H = No BMS Connection with Diagnostics J = BACnet IP with Diagnostics K = BACnet MSTP with Diagnostics L = Modbus IP with Diagnostics M = Modbus RTU with Diagnostics N = LonTalk with Diagnostics
11: Blank
0 = Standard
12: Vestibule Accessories
0 = None C = Vestibule Heating (Electric)
13: Maintenance Accessories
0 = None A = 115VAC Convenience Outlet Factory Wired B = 115VAC Convenience Outlet Field Wired
14: Blank
0 = Standard
15: Code Options
0 = Standard ETL U.S.A. Listing A = Chicago Code
16: Shipping Splits
0 = One Piece Unit
17: Air-Cooled Condenser Accessories
0 = Standard A = Cond Coil Guards C = ECM Condenser Fan Head Pressure Control E = VFD Condenser Fan Head Pressure Control G = Option A + C J = Option A + E
18: Blank
0 = Standard
19: Blank
0 = Standard
20: Blank
0 = Standard
21: Blank
0 = Standard
22: Blank
0 = Standard
23: Blank
0 = Standard
24: Chiller Accessories 1
0 = None A = Glycol chiller C = Thermometers & Pressure Gauges G = Option A + C
25: Blank
0 = Standard
26A: Blank
0 = Standard
26B: Blank
0 = Standard
26C: Blank
0 = Standard
Page 13
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
LF A -
031 - D - 0 - 3 - D A C 0 E - 0 0 0 0 : C 0 - 0 0 0 0 - 0 0 0 0 - 0 0 0 0 - 0 0 - 0 0 0
0 - 0 E 0 0 - 0 0 C 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 D
B
9
10A
10B
10C
10D
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
26D: Blank
0 = Standard
26E: Blank
0 = Standard
26F: Blank
0 = Standard
27: Blank
0 = Standard
28: Blank
0 = Standard
29: Blank
0 = Standard
30: Blank
0 = Standard
31: Blank
0 = Standard
LF Series Feature String Nomenclature
32: Blank
0 = Standard
33: Warranty
0 = Standard Warranty D = Compressor Warranty Years 2-5
34: Cabinet Material
0 = Standard - Double Wall + R-13 Foam Insulation
35: Paint & Special Pricing Authorizations
B = Premium AAON Gray Paint Exterior E = Option B + Shrink Wrap X = Special Pricing Authorization + Premium AAON
Gray Paint Exterior
1 = Option X + Shrink Wrap
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14
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a Factory Trained
The Clean Air Act of 1990 bans the intentional venting of refrigerant as of July 1, 1992. Approved methods of recovery, recycling, or reclaiming
Coils and sheet metal surfaces present sharp edges and care must be taken when working with equipment.
BURNING FOAM INSULATION IS TOXIC! Do not cut holes into any foam insulated panels with any flame producing cutter such as a plasma
Failure to observe the following instructions will result in premature failure of your system and possible voiding of the warranty.

General Description

LF Series air-cooled condenser chillers are complete self-contained liquid chilling units. They are factory assembled, wired, charged and run-tested. Primary pumping package is available as an optional feature.
Service Technician.
System should be sized in accordance with the American Society of Heating, Refrigeration and Air Conditioning Engineers Handbook.
Installation of LF Series units must conform to the ICC standards of the International Mechanical Code, the International Building Code, and local building, plumbing and waste water codes. All appliances must be electrically grounded in accordance with local codes, or in the absence of local codes, the current National Electric Code, ANSI/NFPA 70 or the current Canadian Electrical Code CSA C22.1.
must be followed.
cutter or cutting torch.

Receiving Unit

When received, the unit should be checked for damage that might have occurred in transit. If damage is found it should be noted
on the carrier’s Freight Bill. A request for
inspection by carrier’s agent should be made
in writing at once. Nameplate should be checked to ensure the correct model sizes and voltages have been received to match the job requirements.
Page 15
To prevent motor overheating compressors must cycle off for a
To maintain the proper oil level compressors must cycle on for a
The cycle rate must not exceed 6 starts per hour.
WARNING
Units are equipped with compressor crankcase heaters, which should be energized at least 24 hours prior to cooling operation, to clear any liquid refrigerant from the compressors.
Rotation must be checked on all MOTORS AND COMPRESSORS of three phase units. All motors, to include and not be limited to pump motors and condenser fan motors, should all be checked by a qualified service technician at startup and any wiring alteration should only be made at the unit power connection.
Scroll compressors are directional and will be damaged by operation in the wrong direction. Low pressure switches on compressors have been disconnected after factory testing. Rotation should be checked by a qualified service technician at startup using suction and discharge pressure gauges and any wiring alteration should only be made at the unit power connection.

Chiller

COMPRESSOR CYCLING
5 MINUTE MINIMUM OFF TIME
minimum of 5 minutes.
2 MINUTE MINIMUM ON TIME
minimum of 2 minutes.
Failure to observe the following instructions will result in premature failure of your system, and possible voiding of the warranty.
Before unit operation, the main power switch must be turned on for at least twenty four hours for units with compressor crankcase heaters. This will give the crankcase heater time to clear any liquid accumulation out of the compressor before it is required to run.
CRANKCASE HEATER
OPERATION
Never cut off the main power supply to the unit, except for complete shutdown. When power is cut off from the unit, any compressors using crankcase heaters cannot prevent refrigerant migration. This means the compressor will cool down, and liquid refrigerant may accumulate in the compressor. Since the compressor is designed to pump refrigerant gas, damage may occur when power is restored.
Always control the system from the control panel, never at the main power supply (except for emergency or for complete shutdown of the system).
The standard compressors must be on a minimum of 2 minutes and off for a
15
Page 16
16
Some units may require field wired connections. Refer to the wiring diagrams contained within the unit to identify any components or controls requiring additional wiring in the field before placing the unit into service. All additional field wiring should be performed by a Factory Trained Service Technician.
CAUTION
minimum of 5 minutes. The cycle rate must be no more than 6 starts per hour.
The variable capacity compressors must be on a minimum of 3 minutes and off for a minimum of 3 minutes. The cycle rate must be no more than 10 starts per hour.
The chiller is furnished with a pressure differential switch that is factory installed between the chilled water supply and return connections. This sensor must not be bypassed since it provides a signal to the unit controller that water flow is present in the heat exchanger and the unit can operate without the danger of freezing the liquid.
The compressor life will be seriously shortened by reduced lubrication, and the pumping of excessive amounts of liquid oil and refrigerant.

Wiring Diagrams

A complete set of unit specific wiring diagram in point-to-point form is laminated in plastic and located inside the control compartment door.
FIELD WIRED CONNECTIONS

General Maintenance

When the initial startup is made and on a periodic schedule during operation, it is
necessary to perform routine service checks on the performance of the chiller. This includes reading and recording suction pressures and checking for normal sub­cooling and superheat.

Primary Pumping Package

Primary pumping uses a single pump to move water (or glycol) through the evaporator and back to the building. This pumping package provides the necessary flow of water to the system. The pump is activated whenever the chiller is given a run signal.
Water enters the unit through the return water piping, and then travels through an air scoop to remove any air that is entrapped in the water. Following this, the water flows through a suction guide with strainer. The end of the suction guide is removable for strainer access. The strainer assembly is composed of two parts, the operational strainer, and the startup strainer, (located inside the operational strainer) which is to be removed 24 hours after startup.
The pump is installed after the suction guide, and before a combination valve (Flo­Trex). This combination valve acts as isolation valve, check valve, and flow balancing valve. The shell and tube or brazed plate evaporator, is placed after the combination valve in the water circuit, with a differential pressure switch installed across its inlet and outlet. This pressure switch closes when the differential pressure increases above the set-point, which should be set 1-2 psig below the pressure drop across the heat exchanger at design flow rate. The closing differential pressure switch signals the control system to indicate flow through the heat exchanger and allow cooling to activate as required to maintain the setpoint. The water exiting the shell and
Page 17
tube or brazed plate evaporator, leaves the unit through the water out connection.

Glycol

Glycol units require a glycol feeder field installed to replace fluid that is lost in the system. Water should not be directly added to glycol applications as this would dilute the glycol concentration and thereby increase the freezing temperature of the fluid.

Compression Tank

As the water temperature in the system increases, the volume that water displaces increases. In order to compensate for these forces, AAON recommends a pre­pressurized diaphragm compression tank that is preset for 12 psig.

Pressure Relief Valve

Required pressure relief valve is installed in the unit. This valve is set at 125 psig. Figure 1 shows inlet pressure versus capacity for this pressure relief valve. See appendix for additional information.
Figure 1 - Pressure Relief Valve

Manual and Automatic Air Vent

A manual air vent is supplied in chillers without pumping packages. With a pumping package option, there is an air scoop installed at the high point of the system. The air vent valve must be in the proper
position for operation. Ensure that the small vent cap on the automatic air vent is loosened one to two turns from the closed position, allowing air to be vented from the system. It is advisable to leave the cap on to prevent impurities from entering the valve. See appendix for additional information.

Dual Pumps

When redundant pumping is required, a factory installed dualArm pump can be ordered on units 15 tons and larger. A dualArm pump is a pump with two independent motors and pumps in a single casing. This pump has a swing split-flapper valve in the discharge port to prevent liquid recirculation when only one pump is operating. Isolation valves in the casing allow one pump to be isolated and removed for service while the other pump is still operating.
The controls package will activate the pump when the unit is given a run command. If the controls do not recognize flow in 60 seconds, the second pump will be activated and an alarm signal will be generated. If the second pump does not activate, the cooling will be locked out.

Differential Pressure Gauge and Thermometers

A differential pressure gauge and thermometers are available as a factory installed option when using a factory installed pumping package. Thermometers are installed around the evaporator of the unit. A differential pressure gauge is installed at each pump. This pressure gauge is connected in three places to the water piping: before the suction guide/strainer, after the suction guide and before the pump, and after the pump. There is also a needle valve at each of these points to isolate the pressure. To measure the pressure at any given point, open the needle valve at that
17
Page 18
18
Forks or Fork Extensions must be 72”
in length.
Forks or Fork Extensions must be at least 48” in length.
Forks
point and close the other two needle valves. Instead of two pressure gauges, one pressure gauge is used to minimize calibration and gauge errors.

Pipe Insulation

All evaporators in the LF Series chiller are heat traced and insulated. The water piping and components on standard LF are not heat traced or insulated at the factory. The factory can install heat trace as an optional feature. All water piping shall be leak tested in the field prior to startup, as shipping vibrations may have loosened connections.

Installation

Forklifting the Unit (4-17 and 22-24 ton)

4-17 and 22-24 ton units can be lifted using a forklift. 8, 10-17 and 22-24 ton units must
have forks 72” in length or the forks must
have 72” fork extensions. 4-7 and 9 ton units
must have forks at least 48” in length. Standard units can be lifted from all sides except the condenser side. Units with power exhaust can be lifted from the controls side or the access (right) side. Units with energy
recovery wheels or power return can only be fork lifted from the access (right) side.
Forks must be perpendicular to the unit and they must be in far enough that the back of the forks are no more than 6” away from the edge of the unit.
FORKLIFTING
8, 10-17 AND 22-24 TON UNITS
FORKLIFTING
4-7 AND 9 TON UNITS
Figure 2 - Forklifting an LF Series A, B and C Cabinet, 4-17 and 22-24 tons

Lifting the Unit

If cables or chains are used to hoist the unit they must be the same length. Minimum
cable length is 99” for 4-17 and 22-24 ton units and 180” for 21 and 26-55 ton units.
Care should be taken to prevent damage to the cabinet, coils, and condenser fans. Before lifting unit, be sure that all shipping material has been removed from unit. Secure
Page 19
hooks and cables at all lifting points / lugs provided on the unit.
Hoist unit to a point directly above the curb or concrete pad. Be sure that the gasket material has been applied to curb.
Carefully lower and align the unit with utility and duct openings. Lower the unit until the unit skirt fits around the curb. Some units are designed to overhang the curb. Take care that any recessed base rails fit around the curb. Make sure the unit is level and properly seated on the curb or pad.
Figure 3 - Lifting Details of a 4-17 and 22-24 ton Standard Unit
Figure 4 - Lifting Details of a 21 and 26-55 ton Standard Unit
19
Page 20
20
Location
Clearance
Left
42
Right
36
Compressor End
30
Chiller HXC End
30
Top
Open
Location
Clearance
Left
36
Right
36
Compressor End
30
Chiller HXC End
30
Top
Open
Location
Clearance
Left
42
Right
36
Compressor End
36
Chiller HXC End
30
Top
Open
Location
Clearance
Left
42
Right
42
Compressor End
36
Chiller HXC End
36
Top
Open

Locating the Unit

The LF Series chiller is designed for outdoor applications and mounting at ground level or on a rooftop. It must be placed on a level and solid foundation that has been prepared to support its weight. When installed at ground level, a one-piece concrete slab should be used with footings that extend below the frost line. Also with ground level installation, care must be taken to protect the coil fins from damage due to vandalism or other causes. LF Series chillers are available with factory installed louvered sheet metal condenser coil guards.
The placement relative to the building air intakes and other structures must be carefully selected. Airflow to and from the chiller must not be restricted to prevent a decrease in performance and efficiency.
The installation position must provide at least sufficient clearance for proper airflow to the condenser coils. See Table 1 through Table 4 for individual unit clearances. When units are mounted adjacent to each other, the minimum clearance required between the units is 6 feet
Table 1 - 4-7 & 9 ton Service Clearances
Table 2 - 8 & 10-13 ton Service Clearances
Table 3 - 14-17 & 22-24 ton Service
Clearances
Table 4 - 21 & 26-55 ton Service Clearances
Units should not be installed in an enclosure or pit that is deeper than the height of the unit. When recessed installation is necessary, the clearance to maintain proper airflow is at least 6 feet.
LF Series chillers have a vertical air discharge. There must be no obstruction above the equipment. Do not place the unit under an overhang.
For proper unit operation, the immediate area around condenser must remain free of debris that may be drawn in and obstruct airflow in the condensing section.
Consideration must be given to obstruction caused by snow accumulation when placing the unit.

Water Connection

Connect the chiller supply and return water lines. The connection size is listed on the unit rating sheet, along with the designed volumetric flow rate. The maximum operating pressure for the AAON LF Series chiller is 125 psi.
Page 21
The chiller must be operated only with liquid flowing through the
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. This will result in complete piping system failure.
Installing Contractor is responsible for proper sealing of the water piping and electrical entries into the unit. Failure to seal the entries may result in damage to the unit and property.
evaporators.

Mounting Isolation

For roof mounted applications or anytime vibration transmission is a factor, vibration isolators may be used.

Access Doors

Access doors are provided to the compressor and electrical compartment. A separate
access door is also provided to the evaporator/heat exchanger compartment.

Low Ambient Operation

During low ambient temperatures, it is difficult to start a system because the refrigerant will migrate to the cold part of the system (condenser) and make it difficult for refrigerant to flow. All chiller compressors are provided with factory installed crankcase heaters. The LF Series chiller must have continuous power 24 hours prior to startup. This ensures the compressor will receive sufficient refrigerant vapor at startup. The AAON low ambient (condenser flood­back) system is used to operate a refrigerant system below 25°F outside air temperature. As the ambient temperature drops, the condenser becomes more effective therefore lowering the head pressure.
The low ambient system maintains normal head pressure during periods of low ambient by restricting liquid flow from the condenser to the receiver, and at the same time bypassing hot gas around the condenser to the inlet of the receiver. This reduces liquid refrigerant flow from the condenser, reducing its effective surface area, which in turn increases the condensing pressure. At the same time the bypassed hot gas raises liquid pressure in the receiver, allowing the system to operate properly. LF Series chillers use an LAC valve for low ambient operation.
21
Page 22
22
PERCENTAGE OF CONDENSER TO BE
FLOODED
Ambient
Temperature
(°F)
Evaporating Temperature (°F)
0°
10°
20°
30°
35°
40°
45°
50°
70°
40
24 0 0 0 0 0 0
60°
60
47
33
17
26
20
10
4
50°
70
60
50
38
45
40
33
28
40°
76
68
60
50
56
52
46
42
30°
80
73
66
59
64
60
55
51
20°
86
77
72
65
69
66
62
59
0°
87
83
78
73
76
73
70
68

LAC Valve

The LAC valve is a non-adjustable three way valve that modulates to maintain receiver pressure. As the receiver pressure drops below the valve setting (295 psig for R-410A), the valve modulates to bypass discharge gas around the condenser. The discharge gas warms the liquid in the receiver and raises the pressure to the valve setting. The following schematic shows an example system using the LAC valve.
Figure 5 - Piping Schematic of Example System using the LAC Valve

Condenser Flooding

In order to maintain head pressure in the refrigeration system, liquid refrigerant is kept in the condenser to reduce condenser surface. The following chart shows the percentage that a condenser must be flooded in order to function properly at the given ambient temperature.
Table 5 - Condenser Flooding
Page 23
Electric shock hazard. Before attempting to perform any installation, service, or maintenance, shut off all electrical power to the unit at the disconnect switches. Unit may have multiple power supplies. Failure to disconnect power could result in dangerous operation, serious injury,
Installing Contractor is responsible for proper sealing of the electrical and gas entries into the unit Failure to seal the entries may result in damage to the unit and property.
Convenience outlet and service light circuits are wired to the incoming power side of the disconnect. These circuits will remain powered even when unit disconnect is off.
During higher ambient temperatures the entire condenser is required to condense refrigerant. During these higher ambient temperatures, a receiver tank is used to contain the refrigerant that was required to flood the condenser during low ambient operation. The receiver must be sized to contain all of the flooded volume otherwise there will be high head pressures during higher ambient conditions.

Electrical

The single point electrical power connections are made in the electrical control compartment. The microprocessor control furnished with the unit is supplied with its own power supply factory wired to the main power of the chiller.
Check the unit nameplate voltage to make sure it agrees with the power supply. Connect power to the unit according to the wiring diagram provided with the unit. Note: Units are factory wired for 208V, 230V, 460V, or 575V. In some units, the 208V and 230V options may also be provided in single or three phase configurations. The transformer configuration must be checked by a qualified technician prior to startup.
The power and control wiring may be brought up through the utility entry. Protect the branch circuit in accordance with code requirements. Control wires and power should not be run inside the same conduit. The unit must be electrically grounded in accordance with the current National Electric Code.
Power wiring is to the unit terminal block or main disconnect. All wiring beyond this point has been done by the manufacturer and cannot be modified without effecting the units agency/safety certification.
death or property damage.
Note: Startup technician must check motor amperage to ensure that the amperage listed on the motor nameplate is not exceeded.
CONVENIENCE OUTLETS AND
SERVICE LIGHTS
23
Page 24
24
Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a Factory Trained
Rotation must be checked on all MOTORS AND COMPRESSORS of three phase units. All motors, to include and not be limited to pump motors and condenser fan motors, should all be checked by a qualified service technician at startup and any wiring alteration should only be made at the unit power connection.
Before completing installation, a complete operating cycle should be observed to verify that all components are functioning properly.

Startup

(See back of the manual for startup form.)
Service Technician.
Before startup of the chiller make sure that the following items have been checked.
1. Verify that electrical power is available
to the unit.
2. Verify that any remote stop/start device
connected to the chiller controller is requesting the chiller to start.
3. Verify that liquid flow is present through
the chiller from the building.
4. There should be a building load of at
least 25% of the chiller capacity in order to properly check operation.
5. With the main power switch off, review
the Controller Manual provided with the chiller. Understand the keypad functions, how to set the leaving water temperature setpoint and how to initiate the Run State.
Use the general check list at the top of the startup form to make a last check that all the components are in place, water flow is present, and the power supply is energized.
Using the controller keypad, individually set
the outputs in “Manual On” to confirm relay
closure and compressor operation.
Cycle through all the compressors to confirm that all are operating within tolerance.
While performing the check, use the startup form to record observations of amps and refrigerant pressures.
When all is running properly, place the controller in the Run mode and observe the system until it reaches a steady state of operation.
Note: For more information on programming the controller refer to the MCS Controller manual provided with the unit.
Page 25
Circuit Loading
Max. Pressure Drop
100%
10 psig
50%
5 psig
The Clean Air Act of 1990 bans the intentional venting of refrigerant
(CFC’s and HCFC’s) as of July 1,
1992. Approved methods of recovery, recycling or reclaiming must be followed. Fines and/or incarceration may be levied for non-compliance.

Maintenance

General

Qualified technicians must perform routine service checks and maintenance. This includes reading and recording the condensing and suction pressures and checking for normal sub-cooling and superheat.

Compressors

The scroll compressors are fully hermetic and require no maintenance except keeping the shell clean.

Refrigerant Filter Driers

Each refrigerant circuit contains a filter drier. Replacement is recommended when there is excessive pressure drop across the assembly or moisture is indicated in a liquid line sight glass.
Table 6 - Max Filter Drier Pressure Drops
Evaporator
The evaporators are direct expansion type with an electronic expansion valve to regulate refrigerant. Normally no maintenance or service work will be required.

Adjusting Refrigerant Charge

All AAON chillers are shipped with a full factory charge. Periodically additional charge may be required.
Charging a system in the field must be based on determination of liquid sub-cooling and evaporator superheat. On a system with an electronic expansion valve, liquid sub­cooling is more representative of the charge than evaporator superheat but both measurements must be taken.
Before Charging
Refer to the Unit Nameplate as a reference when determining the proper refrigerant charge.
Unit being charged must be at or near full load conditions before adjusting the charge.
After adding or removing charge the system must be allowed to stabilize, typically 10-15 minutes, before making any other adjustments.
The type of unit and options determine the ranges for liquid sub-cooling and evaporator superheat. Refer to
Table 7 when determining the proper sub­cooling.
Checking Liquid Sub-cooling
Measure the temperature of the liquid line as it leaves the condenser coil.
Read the gauge pressure at the liquid line close to the point where the temperature was taken. You must use liquid line pressure as it will vary from discharge pressure due to condenser coil pressure drop.
Convert the pressure obtained to a saturated temperature using the appropriate refrigerant temperature-pressure chart.
25
Page 26
26
Air-Cooled Condenser
Sub-Cooling
2
12-18°F
Superheat
1
10-15°F
Refrigerant overcharging leads to excess refrigerant in the condenser coils resulting in elevated compressor discharge pressure.
Subtract the measured liquid line temperature from the saturated temperature
Table 7 - Acceptable Refrigeration Circuit
Values to determine the liquid sub-cooling. Compare calculated sub-cooling to the table below for the appropriate unit type and options.
Checking Evaporator Superheat Measure the temperature of the suction line close to the compressor.
Read gauge pressure at the suction line close to the compressor.
Convert the pressure obtained to a saturated temperature using the appropriate refrigerant temperature-pressure chart.
Subtract the saturated temperature from the measured suction line temperature to determine the evaporator superheat.
For refrigeration systems with tandem
1
One compressor running in tandem
2
Two compressors running in tandem
Adjusting Sub-cooling and Superheat Temperatures
The system is overcharged if the sub-cooling temperature is too high and the evaporator is fully loaded (low loads on the evaporator result in increased sub-cooling) and the evaporator superheat is within the temperature range as shown in Table 7 (high superheat results in increased sub-cooling)
Correct an overcharged system by reducing the amount of refrigerant in the system to lower the sub-cooling.
compressors, it is critical that the suction superheat setpoint on the EXV is set with one compressor running. The suction superheat should be 10-13°F with one compressor running. The suction superheat
DO NOT OVERCHARGE!
will increase with both compressors in a tandem running. Inadequate suction superheat can allow liquid refrigerant to return to the compressors which will wash the oil out of the compressor. Lack of oil lubrication will destroy a compressor. Liquid sub-cooling should be measured with both compressors in a refrigeration system running.
Compare calculated superheat to Table 7 for the appropriate unit type and options.
The system is undercharged if the superheat is too high and the sub-cooling is too low.
Correct an undercharged system by adding refrigerant to the system to reduce superheat and raise sub-cooling.
If the sub-cooling is correct and the superheat is too high, the TXV may need adjustment to correct the superheat.
Page 27
°F
PSIG
°F
PSIG
°F
PSIG
°F
PSIG
°F
PSIG
20
78.3
47
134.7
74
213.7
101
321.0
128
463.2
21
80.0
48
137.2
75
217.1
102
325.6
129
469.3
22
81.8
49
139.7
76
220.6
103
330.2
130
475.4
23
83.6
50
142.2
77
224.1
104
334.9
131
481.6
24
85.4
51
144.8
78
227.7
105
339.6
132
487.8
25
87.2
52
147.4
79
231.3
106
344.4
133
494.1
26
89.1
53
150.1
80
234.9
107
349.3
134
500.5
27
91.0
54
152.8
81
238.6
108
354.2
135
506.9
28
92.9
55
155.5
82
242.3
109
359.1
136
513.4
29
94.9
56
158.2
83
246.0
110
364.1
137
520.0
30
96.8
57
161.0
84
249.8
111
369.1
138
526.6
31
98.8
58
163.8
85
253.7
112
374.2
139
533.3
32
100.9
59
166.7
86
257.5
113
379.4
140
540.1
33
102.9
60
169.6
87
261.4
114
384.6
141
547.0
34
105.0
61
172.5
88
265.4
115
389.9
142
553.9
35
107.1
62
175.4
89
269.4
116
395.2
143
560.9
36
109.2
63
178.4
90
273.5
117
400.5
144
567.9
37
111.4
64
181.5
91
277.6
118
405.9
145
575.1
38
113.6
65
184.5
92
281.7
119
411.4
146
582.3
39
115.8
66
187.6
93
285.9
120
416.9
147
589.6
40
118.1
67
190.7
94
290.1
121
422.5
148
596.9
41
120.3
68
193.9
95
294.4
122
428.2
149
604.4
42
122.7
69
197.1
96
298.7
123
433.9
150
611.9
43
125.0
70
200.4
97
303.0
124
439.6
44
127.4
71
203.6
98
307.5
125
445.4
45
129.8
72
207.0
99
311.9
126
451.3
46
132.2
73
210.3
100
316.4
127
457.3
Table 8 - R-410A Refrigerant Temperature-Pressure Chart

Lubrication

All original motors and bearings are furnished with an original factory charge of lubrication. Certain applications require bearings be re-lubricated periodically. The schedule will vary depending on operating duty, temperature variations, or severe atmospheric conditions.
Bearings should be re-lubricated at normal operating temperatures, but not when running.
Rotate the fan shaft by hand and add only enough grease to purge the seals. DO NOT
OVERLUBRICATE.

Service

If the unit will not operate correctly and a service company is required, only a Factory Trained Service Technician qualified and experienced in both refrigerant chillers and air conditioning is permitted to service the system to keep warranties in effect. If assistance is required, the service technician must contact AAON.
27
Page 28
28
Note: Service technician must provide the model and serial number of the unit in all correspondence with AAON.

Warranties

Please refer to the limitation of warranties in effect at the time of purchase.

Condenser Tube Inspection

The coils are leak tested at 650 psig, before shipment. AAON will not be responsible for loss of refrigerant. It is the responsibility of the installer to verify that the system is sealed before charging with refrigerant.

Pump Operation

Before initial start of the pump, check as follows:
1. Be sure that pump operates in the direction indicated by the arrow on the pump casing. Check rotation each time motor leads have been disconnected.
2. Check all connections of motor and starting device with wiring diagram. Check voltage, phase and frequency of line circuit with motor name plate.
3. Check suction and discharge piping and pressure gauges for proper operation.
4. Turn rotating element by hand to assure that it rotates freely.
Running:
Periodically inspect pump while running, but especially after initial start-up and after repairs.
1. Check pump and piping for leaks. Repair immediately.
2. Record pressure gauge readings for future reference.
3. Record voltage, amperage per phase, and kW.
Pump/Fan Motor Maintenance Cleaning - Remove oil, dust, water, and chemicals from exterior of motor and pump. Keep motor air inlet and outlet open. Blow out interior of open motors with clean compressed air at low pressure.
Labeled Motors - It is imperative for repair
of a motor with Underwriters’ Laboratories
label that original clearances be held; that all plugs, screws, other hardware be fastened securely, and that parts replacements be exact duplicates or approved equals. Violation of any of the above invalidates Underwriters’ Label.

Access Doors

If scale deposits or water is found around the access doors, adjust door for tightness. Adjust as necessary until leaking stops when door is closed.

Pump Bearings - Lubrication

Every 6 months or after a prolonged shut down, use waterproof, lithium based grease. Below 32°F, use Esso Exxon or Beacon 325. Above 32°F, use Mobil Mobilox EP2, Shell Alvania EP2 or Texaco RB2.

Air Inlet

Inspect the air inlet louvers into the condenser section on a monthly basis to remove any paper, leaves or other debris that may block the airflow.

Propeller Fans and Motors

The fans are directly mounted on the motor shafts and the assemblies require minimal maintenance except to assure they are clear of dirt or debris that would impede the airflow.
Page 29
Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.
Harsh chemicals, household bleach, or acid cleaners should not be used to clean outdoor or indoor e-coated coils. These cleaners can be very difficult to rinse out of the coil and can accelerate corrosion and attack the e-coating. If there is dirt below the surface of the coil, use the recommended coil cleaners.
CAUTION

Recommended Annual Inspection

In addition to the above maintenance activities, a general inspection of the unit surface should be completed at least once a year.

Mechanical Cleaning

Do not attempt to mechanically clean the copper tubing in the condenser. Do not use wire brushes or any other mechanical device on the copper tubing. Severe damage may result. Contact your water treatment expert for recommendations on chemical cleaning procedures.

Air-Cooled Condenser

The air-cooled condenser section rejects heat by passing outdoor air over the microchannel coils for cooling of the hot refrigerant gas from the compressors. The heated air will discharge from the top of the section through the axial flow fans.
The condenser coils should be inspected yearly to ensure unrestricted airflow. If the installation has a large amount of airborne dust or other material, the condenser coils should be cleaned with a water spray in a direction opposite to airflow. Care must be taken to prevent bending of the aluminum fins on the copper tubes.

E-Coated Coil Cleaning

Documented routine cleaning of e-coated coils is required to maintain coating warranty coverage.
Surface loaded fibers or dirt should be removed prior to water rinse to prevent restriction of airflow. If unable to back wash the side of the coil opposite of the coils entering air side, then surface loaded fibers or dirt should be removed with a vacuum cleaner. If a vacuum cleaner is not available, a soft non-metallic bristle brush may be used. In either case, the tool should be applied in the direction of the fins. Coil surfaces can be easily damaged (fin edges bent over) if the tool is applied across the fins.
Use of a water stream, such as a garden hose, against a surface loaded coil will drive the fibers and dirt into the coil. This will make cleaning efforts more difficult. Surface loaded fibers must be completely removed prior to using low velocity clean water rinse.
A monthly clean water rinse is recommended for coils that are applied in coastal or industrial environments to help to remove chlorides, dirt, and debris. It is very important when rinsing, that water temperature is less than 130° F and pressure is less than 900 psig to avoid damaging the fin edges. An elevated water temperature (not to exceed 130° F) will reduce surface tension, increasing the ability to remove chlorides and dirt.
29
Page 30
30
High velocity water from a pressure washer or compressed air should only be used at a very low pressure to prevent fin and/or coil damages. The force of the water or air jet may bend the fin edges and increase airside pressure drop. Reduced unit performance or nuisance unit shutdowns may occur.
CAUTION
Quarterly cleaning is essential to extend the life of an e-coated coil and is required to maintain coating warranty coverage.
Coil cleaning shall be part of the unit’s regularly scheduled maintenance procedures. Failure to clean an e-coated coil will void the warranty and may result in reduced efficiency and durability.
For routine quarterly cleaning, first clean the coil with the following approved coil cleaner. After cleaning the coils with the approved cleaning agent, use the approved chloride remover to remove soluble salts and revitalize the unit.

Recommended Coil Cleaner

The following cleaning agent, assuming it is used in accordance with the manufacturer’s directions on the container for proper mixing and cleaning, has been approved for use on e-coated coils to remove mold, mildew, dust, soot, greasy residue, lint, and other particulate: Enviro-Coil Concentrate, Part Number H­EC01.

Recommended Chloride Remover

CHLOR*RID DTS™ should be used to remove soluble salts from the e-coated coil, but the directions must be followed closely. This product is not intended for use as a degreaser. Any grease or oil film should first
be removed with the approved cleaning agent.
Remove Barrier - Soluble salts adhere to the substrate. For the effective use of this product, the product must be in contact with the salts. These salts may be beneath any soils, grease or dirt; therefore, these barriers must be removed prior to application of this product.
Apply CHLOR*RID DTS - Apply directly onto the substrate. Sufficient product must be applied uniformly across the substrate to thoroughly wet out surface, with no areas missed. This may be accomplished by use of a pump-up sprayer or conventional spray gun. The method does not matter, as long as the entire area to be cleaned is wetted. After the substrate has been thoroughly wetted, the salts will be soluble and is now only necessary to rinse the salts off.
Rinse - It is highly recommended that a hose be used. A pressure washer on a high pressure setting will damage the fins. The water to be used for the rinse is recommended to be of potable quality, though a lesser quality of water may be used if a small amount of CHLOR*RID DTS is added. Check with CHLOR*RID International, Inc. for recommendations on lesser quality rinse water.

Microchannel Coil Cleaning Cleaning microchannel coils is necessary in all locations. In some locations it may be necessary to clean the coils more or less often than recommended. In general, a condenser coil should be cleaned at a minimum of once a year. In locations where there is commonly debris or a condition that causes dirt/grease build up it may be necessary to clean the coils more often. Proper procedure should be followed at every cleaning interval. Using improper

Page 31
Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.
WARNING
cleaning technique or incorrect chemicals will result in coil damage, system performance fall off, and potentially leaks requiring coil replacement.
Documented routine cleaning of microchannel coils with factory provided e­coating is required to maintain coating warranty coverage. Use the E-Coated Coil Cleaning section for details on cleaning e­coated coils.
Field applied coil coatings are not recommended with microchannel coils.
Allowed Chemical Cleaners and Procedures
AAON recommends certain chemicals that can be used to remove buildup of grime and debris on the surface of microchannel coils. These chemicals have been tested for performance and safety and are the only chemicals that AAON will warrant as correct for cleaning microchannel coils. There are three procedures that are outlined below that will clean the coils effectively without damage to the coils. Use of any other procedure or chemical may void the warranty to the unit where the coil is installed. With all procedures make sure the unit is off before starting.
#1 Simple Green
Simple Green is available from AAON Parts and Supply (Part# T10701) and is biodegradable with a neutral 6.5 pH. Recommendation is to use it at a 4 to 1 mix. Use the following procedure.
1. Rinse the coil completely with water.
Use a hard spray but be careful not to bend or damage the fins. A spray that is too hard will bend the fins. Spray from the fan side of the coil.
2. With a pump sprayer filled with a mix of
4 parts water to one part Simple Green spray the air inlet face of the coil. Be sure to cover all areas of the face of the coil.
3. Allow the coil to soak for 10-15 minutes.
4. Rinse the coil with water as in step one.
5. Repeat as necessary.
#2 Vinegar
This is standard white vinegar available in gallons from most grocery stores. It has a pH of 2-3, so it is slightly acidic. Use the following procedure.
1. Rinse the coil completely with water.
Use a hard spray but be careful not to bend or damage the fins. A spray that is too hard will bend the fins. Spray from the fan side of the coil.
2. Use a pump sprayer filled with vinegar
(100%). Spray from the face of the coil
The water pressure used to clean should not exceed 140 psi, from no closer than 3 inches from the coils, and with the water aimed perpendicular to the coils.
in the same direction as the airflow. Be sure to cover all areas of the face of the coil.
3. Allow the coil to soak for 10-15 minutes.
4. Rinse the coil with water as in step one.
5. Repeat as necessary.
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Use pressurized clean water, with pressure not to exceed 140 psi. Nozzle should be 6” and 80° to 90° from coil face. Failure to do so could result in coil damage.
CAUTION
#3 Water Flush
This procedure can be used when the only material to cause the coil to need cleaning is debris from plant material that has impinged the coil face.
1. Rinse the coil completely with water.
Use a hard spray but be careful not to bend or damage the fins. A spray that is too hard will bend the fins. Spray from the fan side of the coil.
2. Spray and rinse the coil from the face.
Other Coil Cleaners
There are many cleaners on the market for condenser coils. Before using any cleaner that is not covered in this section you must get written approval from the AAON warranty and service department. Use of unapproved chemicals will void the warranty.
AAON testing has determined that unless a chemical has a neutral pH (6-8) it should not be used.
Beware of any product that claims to be a foaming cleaner. The foam that is generated is caused by a chemical reaction to the aluminum fin material on tube and fin coils and with the fin, tube, and coating material on microchannel coils.
Microchannel coils are robust in many ways, but like any component they must be treated
Application Examples
The three procedures can be used to clean microchannel coils. They will fit with the application depending on the area. In some areas where the spring/summer has a large cottonwood bloom #3 might work fine if the unit is installed on an office building and no other environmental factors apply.
When a unit is installed where the sprinkler system has water being sprayed onto the condenser coil you might have better results using #2. Vinegar is slightly acidic and may help with the calcium build up from drying water. This also works well when grease is part of the inlet air to a condenser coil.
Generally the best and broadest based procedure is #1. The grease cutting effect of the Simple Green is good for restaurant applications.
correctly. This includes cleaning the coils correctly to give optimal performance over many years.

Replacement Parts

Parts for AAON equipment may be obtained by contacting your local AAON representative. When ordering parts, reference serial number and part number located on the external or internal nameplate of the unit.

AAON - Longview Warranty, Service, and Parts Department

203 Gum Springs Rd. Longview, TX 75602 Ph: 903-236-4403 Fax: 903-236-4463 www.aaon.com
Note: Before calling, technician should have model and serial number of the unit available for the customer service department to help answer questions regarding the unit.
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Appendix - Water Piping Component Information

Water Pressure Relief Valve

Overview
ASME Rated, Design Certified and Listed by C.S.A.
Used for protection against excessive pressure on domestic storage tanks or tank­less water heaters, the pressure relief valve has no temperature relieving element. Standard setting is 125 psi Size 3⁄4” x 3⁄4” (20mm x 20mm). ASME construction and is tested, listed and certified by the National Board of Boiler and Pressure Vessel Inspectors.
ANSI Z21.22 “Relief Valves for Hot Water
Supply Systems.”
DESIGN CERTIFIED and listed by C.S.A.

Automatic Air Vent Valves

Automatic Air Vent Valves provide air venting for hot or cold water distribution systems. These vents purge air that may be in the water system.
The vent valve utilizes an internal baffle system. The baffles slow water so that entrapped air can separate. Once the air is separated, the air migrates to the top of the scoop chamber. The air is vented through the factory installed vent.
Overview
Air scoops are constructed of one piece cast iron. Baffles are engineered to separate air
from water. All air scoops come with 1/8”
vent connection. An additional stainless steel expansion tank connection is available on the 1-1/2” to 4” air scoops. Air scoops never require servicing. The high point vent should be turned clockwise one to two rotations to allow proper air venting. It is not recommended to remove the cap as dirt and debris may enter the water system.
Air scoops are suitable for use with water or water/glycol systems.
Operating Range
Maximum operating pressure:
125 psi (862 kPa)
Maximum operating temperature:
Recommended Flow Rate:
Maximum Flow Rate:
300ºF (135ºC)
4 ft. / sec.
8 ft. / sec.
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Dimensions & Weights
Product
Number
Size A B C D E F
Cv
Weight
Lbs
Kg.
431
1”
6”
4”
2-1/2”
**
1/2” NPT
1/8” NPT
31.4 4 1.8
432
1-1/4”
6”
4”
2-1/2”
**
1/2” NPT
1/8” NPT
53.5 4 1.8
433
1-1/2”
8”
6”
4”
3/4” NPT
1/2” NPT
1/8” NPT
61 7 3.2
434
2”
8”
6”
4”
3/4” NPT
1/2” NPT
1/8” NPT
106.6 7 3.2
435
2-1/2
10”
8”
5-1/2”
1” NPT
1/2” NPT
1/8” NPT
140
15
6.8
436
3”
10”
8”
5-1/2”
1-1/4” NPT
1/2” NPT
1/8” NPT
276
14
6.4
437*
4”
16-5/16”
11-5/8”
7-1/8”
1-1/2” NPT
1/2” NPT
1/8” NPT
600
52
23.6
*This size has 125 lb. flanged ends. **No conventional plain steel expansion tank tapping.
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Installation and service must be performed by a Factory Trained Service Technician.
Installation of this equipment should not take place unless this document

Pumps: Installation and Operating Instructions

Introduction
This document contains specific information regarding the safe installation, operating and maintenance of Vertical In-Line pumps and should be read and understood by installing, operating and maintenance personnel. The equipment supplied has been designed and constructed to be safe and without risk to health and safety when properly installed, operated and maintained. The instructions following must be strictly adhered to. If clarification is needed on any point please contact Armstrong quoting the equipment serial number.
has been read and understood.
Where under normal operating conditions the limit of 68°C/155°F (Restricted Zone) for normal touch, or 80°C/176°F (Unrestricted Zone) for unintentional touch, may be experienced, steps should be taken
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to minimize contact or warn operators/users that normal operating conditions will be exceeded. In certain cases where the temperature of the pumped liquid exceeds the above stated temperature levels, pump casing temperatures may exceed 100°C/212°F and not withstanding pump insulation techniques appropriate measures must be taken to minimize risk for operating personnel.
Storage
Pumps removed from service and stored, must be properly prepared to prevent excessive rusting. Pump port protection plates must not be removed until the pump is ready to connect to the piping. Rotate the shaft periodically (At least monthly) to keep rotating element free and bearings fully functional.
For long term storage, the pump must be placed in a vertical position in a dry environment. Internal rusting can be prevented by removing the plugs at the top and bottom of the casing and drain or air blow out all water to prevent rust buildup or the possibility of freezing. Be sure to reinstall the plugs when the unit is made operational. Rust proofing or packing the casing with moisture absorbing material and covering the flanges is acceptable. When returning to service, be sure to remove the drying agent from the pump.
Handling Large VIL Units
One effective way of lifting a large pumping unit is to place lifting hooks through the motor lifting rings or straps around the upper part of the motor. The pump and motor unit will free-stand on the casing ribs. Remove the coupling guard and place (2) lifting straps through the pump/motor pedestal, one on each side of the motor shaft and secure to the lifting device.
With the straps in place, using a spacer bar if necessary to protect the motor fan cover, the whole assembly can now be lifted securely.
Note: Handling, transportation and installation of this equipment should only be undertaken by trained personnel with proper use of lifting equipment.
Remove coupling guard and place lifting straps on each side of coupling, use spacer bar if necessary to protect motor fan cover.
Vertical Inline Pump Lifting Strap Positioning:
Note:
All split-coupled pumps contain a tapped hole in the motor bracket above the discharge flange for draining the well. Pipe this drain hole to a floor drain to avoid overflow of the cavity caused by collecting chilled water condensate or from seal failure.
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Piping may carry high temperature fluid.
Discharge valve only is to be used to throttle pump flow.
Do not run pumps with discharge valve closed or under very low flow
Pump Piping - General
The pump must be fully primed on start up. Fill the pump casing with liquid and rotate the shaft by hand to remove any air trapped in the impeller. On split coupled units, any air trapped in the casing as the system is filled must be removed by the manual air vent in the seal flush line. Close-coupled units are fitted with seal flush/vent lines piped to the pump suction area. When these units operate residual air is drawn out of the pump towards the suction piping.
Energize the motor momentarily and check
Caution
The discharge valve only is to be used to throttle pump flow, not the suction valve. Care must be taken in the suction line layout and installation, as it is usually the major source of concern in centrifugal pump applications
Alignment
Alignment is unnecessary on close-coupled pumps as there is no shaft coupling.
Split-coupled units are accurately aligned at the factory prior to being shipped and do not need re-aligning when installed.
Operation
that the rotation corresponds with the directional arrow on the pump casing.
To reverse rotation of a three phase motor, interchange any two power leads.
Start the pump with the discharge valve closed and the suction valve open, and then gradually open the discharge valve when the motor is at operating speed. The discharge valve may be opened slightly at start up to help eliminate trapped air.
When stopping the pump: Close the discharge valve and de-energize the motor.
DO NOT run the pump against a closed discharge valve for an extended period of time (A few minutes maximum).
Star-Delta motor starters should be fitted with electronic/mechanical interlocks that have a timed period of no more than 40 milliseconds before switching from star
conditions.
Starting Pump
Ensure that the pump turns freely by hand, or with some mechanical help such as a strap and lever on larger pumps. Ensure that all protective guarding is securely fixed in position.
(Starting) to delta (Run) connection yet allow the motor to reach full star (Starting) speed before switching to delta (Run).
Should the pump be noisy or vibrate on start-up a common reason is overstated system head. Check this by calculating the pump operating head by deducting the suction pressure gauge value from the
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Check rotation arrow prior to operating the unit.
Electric shock hazard. Before attempting to perform any service or maintenance on pumping unit, disconnect power source to drive, LOCK IT OFF and tag with the reason.
discharge gauge reading. Convert the result into the units of the pump head as stated on the pump nameplate and compare the values. Should the actual pump operating head be significantly less than the nameplate head value it is typically permissible to throttle the discharge isolation valve until the actual operating head is equal to the nameplate value.
Any noise or vibration usually disappears. The system designer or operator should be made aware of this soon as some adjustment may be required to the pump impeller diameter or drive settings, if applicable, to make the pump suitable for the system as installed.
Check rotation arrow prior to operating the unit. The rotation of all Vertical In-Line
units is “clockwise” when viewed from the
drive end. (Looking from on top of / behind the motor)
General Care
Vertical In-Line pumps are built to operate without periodic maintenance, other than motor lubrication on larger units. A systematic inspection made at regular intervals, will ensure years of trouble-free operation, giving special attention to the following:
Keep unit clean. Keep moisture, refuse, dust or other loose particles away from the pump and ventilating openings of the motor
Avoid operating the unit in overheated surroundings (Above 100ºF/40ºC).
Any possibility of the unit starting while being serviced must be eliminated.
If mechanical seal environmental accessories are installed, ensure water is flowing through the sight flow indicator and that filter cartridges are replaced as recommended.
Pump Lubrication Lubrication is not required. There are no bearings in the pump that need external lubrication service.
Motor Lubrication Follow the lubrication procedures recommended by the motor manufacturer. Many small and medium sized motors are permanently lubricated and need no added lubrication. Generally if there are grease fittings evident the motor needs periodic lubrication, and if there are no grease fittings evident, no periodic lubrication is required.
Check the lubrication instructions supplied with the motor for the particular frame size indicated on the motor nameplate.
Mechanical Seal
Mechanical seals require no special attention. The mechanical seal is fitted with a flush line. The seal is flushed from discharge of the pump casing on split­coupled pumps and is flushed and vented to the suction on close coupled pumps.
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Double Check Prior to Startup.
The split-coupled pump is flushed from the pump discharge because the mechanical seal chamber is isolated from the liquid in the pump by a throttle bushing. Because the seal chamber is isolated, seal environmental controls such as filters and separators, when
all detrimental to the pump internals and sealing arrangement.
Proper operation cannot be guaranteed if the above conditions are not adhered to.
installed in the split-coupled flush line are very effective, as only the seal chamber needs cleansing, and will prolong seal life in HVAC systems.
Do not run the pump unless properly filled with water as the mechanical seals need a film of liquid between the faces for proper operation.
Mechanical seals may ‘weep’ slightly at
start-up. Allow the pump to continue operating for several hours and the mechanical seal to ‘seat’ properly prior to calling for service personnel.
System Cleanliness
Before starting the pump the system must be thoroughly cleaned, flushed and drained and replenished with clean liquid.
Welding slag and other foreign materials,
“Stop Leak” and cleaning compounds and
improper or excessive water treatment are
Note:
Particular care must be taken to check the following before the pump is put into operation:
1. Pump primed?
2. Rotation OK?
3. Lubrication OK?
4. Pipe work properly supported?
5. Voltage supply OK?
6. Overload protection OK?
7. Is the system clean?
8. Is the area around the pump clean?
Warranty
Does not cover any damages to the equipment resulting from failure to observe the above precautions.
Noise Levels
Estimated Pumping Unit Sound Power Level, (Decibels), A-Weighted, at 1 m (3 ft.) from unit.
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Vibration Levels
Vertical In-Line pumps are designed to meet vibration levels set by Hydraulic Institute Standard HI Pump Vibration 9.6.4. Standard levels are as detailed below:

Dual Pump Specific Information

Dual Pump Flapper Valve Operating Instructions
This unit is fitted with internal valves to allow isolation of one pump for service and to automatically prevent recirculation of the flow when only one pump is running.
Procedure for Parallel or Stand-By Pumping:
Discharge and suction valve stems should be locked in the center position. This is indicated by both locking handles in the vertical position and the center pin of the locking arms (4) locked by the handles. This procedure allows the discharge flapper valves to pivot freely and locks the suction valve firmly in the center position.
Procedure for Isolation of One Side:
1. Stop the pump to be serviced.
2. Close and lock the suction and discharge
valves: as per instructions below.
3. Ensure seal flush line interconnection valve is closed and drain the isolated casing.
4. Service isolated pump as required.
Procedure for Starting the Pump after Servicing:
1. Ensure serviced pump is fully re-
assembled including all seal flush lines and drain plugs.
2. Fill the dry casing with system fluid by opening the seal flush line interconnecting valve and the air vent fitting.
3. Allow the pressure to equalize in the two casings, if necessary, by opening seal flush line interconnected valve.
4. Unlock the discharge valve as per instructions below.
5. Unlock the suction valve as per instructions below.
NOTE: Keep hands and tools away from locked suction valve arm, as the differential pressure may cause the arm to rotate quickly with force when unlocked.
6. Close the seal flush line interconnect valve and restart pump.

Valve Operation

Refer to the valve illustrations on the following pages.
Discharge Valve
This valve performs the dual function of automatically sealing the discharge of the
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40
Care should be taken when performing procedures 3 and 4. Read
inactive pump when one pump is running and can manually be closed and locked to isolate one pump for service.
Automatic Flapper Operation
In the flapper mode the two halves of the discharge valve are free to pivot independently under normal operating conditions. The locking handle (3) should be secured with the set screw (11) in the vertical position with the center pin of the locking arm (4) trapped by the locking handle (3).
Manual Valve Locking:
The locking feature of this valve is to ensure a positive seal (leak proof) of the discharge port on the pump to be serviced.
Note: Ensure the pump to be isolated is not operating before attempting to release the locking mechanism. Failure to do so may result in injury to the operator and/or damage to the pump.
Locking
1. Loosen discharge side set screw (11) to
release the locking handle (3).
2. Rotate the discharge side locking handle (3) so that the handle points toward the pump to be serviced and secure in the horizontal position, using set screw (11). This releases the discharge locking arm (4).
3. Rotate discharge valve shaft (16) towards the pump to be isolated. The orientation of
THIS HANDLE SHOULD NOT BE ROTATED PAST THE VERTICAL POSITION.
Note: Ensure the isolated pump is not
operating before attempting to release the locking mechanism. Failure to do so may result in injury to the operator and/or damage the pump.
Unlocking:
1. Open the interconnecting valve on the
seal flush line to pressurize the serviced pump and vent air through bleeder valve on series 4302. Close these valves once the pressure is equalized and air removed.
2. Loosen set screw (11) and lower locking handle (3) to the horizontal position, secure with set screw (11).
3. Rotate valve to center position so that the center pin of the locking arm (4) locates in the recess on the locking handle (3).
4. Loosen set screw (11) and raise locking arm (3) to the vertical position, locking the center pin in the locking arm recess, secure with set screw (11).
Suction Valve Manual Operation:
The suction side valve is designed for use as a manually operated isolation valve. This valve is not designed to automatically pivot as the discharge flappers do.
the shaft is indicated by the center pin on the locking arm. (4).
4. Raise the locking handle (3) so that the cam on the base of the handle forces the pin of the locking arm (4) towards the pump to be isolated. The locking handle (3) should be raised to between 45 degrees and the vertical position.
5. Tighten set screw (11) to lock the locking handle (3) in position
instructions carefully.
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Care should be taken when performing procedures 3 and 4. Read
Locking:
1. Loosen suction side set screw (11) to
release the locking handle (3).
2. Rotate the suction side locking handle (3) so that the handle points towards the pump to be serviced and secure in the horizontal position, using set screw (11). This releases the suction locking arm (4).
Note: The locking handle (3) should only be rotated towards the pump stopped for service. The suction valve is designed to prevent the locking handle (1) from rotating towards the running pump, as the suction of the running pump could cause the valve to slam shut with sufficient force to injure the operator and/or cause damage to the pump. Do not attempt to circumvent this safety feature.
3. Rotate the suction valve towards the pump to be isolated. The orientation of the shaft is indicated by the center pin on the locking arm (4).
4. Loosen set screw (11) and raise the locking handle (3) so that the cam on the base on the handle forces the pin of the locking arm (4) towards the pump to be isolated. The locking handle (3) should be raised to between 45 degrees and the vertical position.
THIS HANDLE SHOULD NOT BE ROTATED PAST THE VERTICAL POSITION.
5. Tighten set screw (11) to secure the
locking handle (3) in position.
instructions carefully.
Unlocking:
1. Open the interconnecting valve on the
seal flush line to pressurize the serviced pump and vent air through bleeder valve on series 4302. Close these valves once the pressure is equalized and air removed.
2. Loosen set screw (11) and lower locking handle (3) to the horizontal position, secure with set screw (11).
NOTE: Keep hands and tools away from suction valve locking arm when freed by locking handle as differential pressure may cause arm to rotate quickly with force when unlocked.
3. Rotate valve to center position so that the center pin of the locking arm (4) is located in the recess on the locking handle (3).
4. Loosen set screw (11) and raise locking arm (3) to the vertical position, locking the center pin in the locking arm recess, secure with set screw.
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Suction Guides

Introduction
Suction guides are designed for bolting directly onto the suction flange of horizontal or vertical shaft centrifugal pumps.
Operating Limits
The suction guide is designed to be a four­function fitting. Each Suction Guide is a 90º
elbow, a Pipe Strainer and a Flow Stabilizer. It may also be used as a Reducing Elbow, should the suction piping be larger than the pump inlet.
Installation
The suction guides may be installed in any arrangement feasible the arrangement of the pump flange bolt-holes.
Inspection
Suction guides are thoroughly tested and inspected before shipment to assure they meet with your order requirements. All units must be carefully examined upon arrival for possible damage during transit. Any evidence of mishandling should be reported immediately to the carrier and noted on the freight bill.
Operation
No special attention need be paid to the Suction Guide at start-up. The fitting is stationary and will strain the pumped fluid and stabilize the flow into the pump automatically.
Temporary strainer must be removed following system clean up.
After all debris has been removed from the system, or a maximum of 24 running hours, stop the pump and close the pump isolation valves. Drain the Suction Guide by removing the drain plug or opening the blowdown valve, if installed.
Remove the Suction Guide cover and remove the strainer assembly from the valve body.
A temporary fine-mesh start-up strainer is tack-welded to the permanent stainless steel strainer. This temporary strainer should now be removed from the permanent strainer. The fine-mesh strainer is designed to remove small particulate from new piping systems and could easily clog with debris if left in place. This will be detrimental to the operation of the pump.
Inspect the cover O-ring and replace if necessary.
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Armgrip Flange Adapter Details
Valve Size
125 psi/150 psi
250 psi/300 psi
Ductile Iron Bolt
Ductile Iron Bolt
No.
Size
No.
Size
2-1/2
4
5/8 8 3/4 3 4
5/8 8 3/4 4 8
5/8 8 3/4 5 8
3/4 8 3/4 6 8
3/4
12
3/4 8 8
3/4
12
7/8
10
12
7/8
16 1 12
12
7/8
16
1-1/8
Replace the permanent strainer into the fitting body, once the temporary strainer is removed.
Replace the cover into the body. Ensuring that the strainer is properly seated, tighten the cover bolts diagonally, evenly and firmly.

Flo-Trex Combination Valve

Introduction
The Flo-Trex combination valves are designed for installation on the discharge side of centrifugal pumps, and incorporate three functions in one valve:
1. Drip-tight shut-off valve
2. Spring closure design, Non-slam check
valve
3. Flow throttling valve
Armgrip Flange Adapter installation
1. Position the two halves of the Armgrip
flange adapter on the valve body ensuring that the lugs on each half of the flange adapters are located between the anti­rotation lugs on the valve body (as shown).
Insert two bolts of specified size (Table A1) to secure the halves of the flange adapter to the valve body (as shown).
The gasket cavity should face out to the adjoining flange.
2. Lubricate the inner and outer diameter of the gasket with the lubricant provided or a similar non-petroleum based water soluble grease.
3. Press the gasket firmly into the flange cavity ensuring that the sealing lip is pointed outward. When in place, the gasket should not extend beyond the end of the pipe (as shown).
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Safety glasses should be worn. Probes should not be left inserted into fittings for long periods of time as leakage may result.
4. Position the adjoining flange or the pipe to the Armgrip flange adapter and install the remaining bolts. The two locking bolts should be tightened first in order to position the flange correctly.
Note: Care should be taken to ensure that the gasket is not pinched or bent between flanges.
5. Tighten remaining nuts evenly by
following bolting instructions, so that the flange faces remain parallel (as shown in the figure labeled Recommended Bolt Tightening Procedure).
Flange bolts should be tightened to 70 ft-lbs torque minimum to assure firm metal to metal contact. When raised face flanges are sued, there will be a gap between the faces of the outer diameter.
6. Flange gaskets are not interchangeable with other mechanical pipe couplings or flange gaskets.
2. Remove the body bolts from valve body using Allen Key
3. Rotate one half of the valve body 180° making sure the lower valve seat and O ring stay in position. Inspect the O ring for any cuts or nicks and replace if necessary
4. Replace body bolts and torque evenly to 70 ft-lbs.
Flow Measurement with the valve in the Wide Open position:
Where approximate indication of flow is acceptable the Flo-Trex valve can be used.
Step 1. Measure and record the differential pressure across the valve.
Step 2. With valve in fully open position, locate the differential pressure on the Performance curve, and for the given valve size in use, read the corresponding flow rate.
Flow Measurement with the valve in the throttled position:
Step 1. The valve stem with its grooved
rings and positioning sleeve is the flow indicator scale for the throttled position of the valve.
Recommended Bolt Tightening Procedure Field Conversion (Straight to Angle Pattern Valve)
1. Open valve at least one complete turn.
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Valve Size
2-1/2
3 4 5 6 8
10
12
Number
of Rings
(valve fully
open)
5 5 6 9 10
12
18
28
The quarter turn graduations on the sleeve, with the scribed line on the stem provide an approximate flow measurement.
Note: The valve is shipped in closed position. The indicator on the plastic sleeve is aligned with the vertical scribed line on the stem.
Step 2. Record the size of the valve and
stem position using the flow indicator scale. Calculate the percentage of valve opening based on the number of rings at the fully open position.
Step 5. Locate the differential pressure determined for the valve in the throttled position on the Flo-Trex Performance Curve. Determine the flow rate for the given valve size at this differential pressure.
Step 3. Measure and record the differential pressure across the valve in the throttled position.
Step 4. Locate percentage of valve opening on the flow characteristic curve. For the given valve, record the percentage of maximum flow rate.
Step 6. Calculate the flow rate of the valve in the throttled position by multiplying the flow rate (Step 5) by the percentage of maximum flow rate (Step 4).
Example:
Valve size: 4 in. Differential pressure is 5.4 ft Number of open rings is 3. From the table, the number of rings for the 4 in valve fully open is 6. Divide open rings by total, 3/6 = 50% throttled
From the Flo-Trex performance curve, a 4 in. valve with 5.4 ft of pressure drop represents a flow of 400 Usgpm
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100
34) x (400
100
34) x (25.2
From the flow characteristic curve, a 4 inch valve at 50% open represents 34% of maximum flow.
The approximate flow of a 4 inch valve with a 5.4 ft pressure drop when 50% throttled is:
=136 US gpm;
=8.57 L/s
Note: To prevent premature valve failure it is not recommended that the valve operate in the throttled position with more than 25 ft pressure differential. Instead the pump impeller should be trimmed or valves located elsewhere in the system to partially throttle the flow.
Operation
To assure tight shut-off, the valve must be closed using a wrench with 25 to 30 ft-lbs of torque.
To assure trouble free check valve operation and shut-off operation, the valve should be periodically opened and closed to keep valve seat and valve disc guide stem from accumulating system contaminants.
Repacking of Flo-Trex valve under full system pressure
If it is necessary, the stem O ring can be changed under full system pressure.
Safety glasses should be worn.
Step 1. Record the valve setting.
Step 2. Turn the valve stem
counterclockwise until the valve is fully open and will not turn any further. Torque
to a maximum of 45 ft-lbs. This will ensure good metal to metal contact and minimal leakage.
Step 3. The valve bonnet may now be removed. There may be a slight leakage, as the metal to metal backseating does not provide a drip-tight seal.
Step 4. Clean exposed portion of valve stem being careful not to leave scratches.
Step 5. Remove and replace the O ring gasket.
Step 6. Install the valve bonnet.
Step 7. Tightening the valve bonnet is
necessary to stop any leaks.
Step 8. Open valve to balance set point as recorded in Step 1.
Note: On valve sizes of 2-1/2 inch and 3 inch, the full open position is 5 turns, though the valve will open to 5-1/2 turns which is just back of seating of valve.
Seat Replacement: Step 1. Drain the system and remove valve
from piping.
Step 2. Remove the body bolts from the body using an Allen Key.
Step 3. Remove seat and O Ring. O rings are not used on valves of 8 inches or larger.
Step 4. Inspect and clean O ring cavity and install new O ring and seat. Valve disc stem should be inspected and replaced if worn. Valve stem O ring should be replaced at this time as discussed under Repacking of Flo­Trex section.
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Pressure-Temperature Limits:
Flo-Trex Cross Section
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Job Name:_______________________________________________
Date:______________
Address:______________________________________________________________________
______________________________________________________________________________
Model Number:_________________________________________________________________
Serial Number:_____________________________________________
Tag:_______________
Startup Contractor:______________________________________________________________
Address:______________________________________________________________________
_______________________________________________________
Phone:______________
Installing contractor should verify the following items.
1. Is there any visible shipping damage?
Yes No
2. Is the unit level?
Yes No
3. Are the unit clearances adequate for service and operation?
Yes No
4. Do all access doors open freely and are the handles operational?
Yes No
5. Have all shipping braces been removed?
Yes No
6. Have all electrical connections been tested for tightness?
Yes No
7. Does the electrical service correspond to the unit nameplate?
Yes No
8. On 208/230V units, has transformer tap been checked?
Yes No
9. Has overcurrent protection been installed to match the unit nameplate
requirement?
Yes No
10. Have all set screws on the fans been tightened?
Yes No
11. Do all fans rotate freely?
Yes No
12. Does the field water piping to the unit appear to be correct per design
parameters?
Yes No
Ambient Dry Bulb Temperature ________°F
Ambient Wet Bulb Temperature ________°F
Pre Startup Checklist

LF Series Startup Form

Ambient Temperature
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51
Water/Glycol System
1. Has the entire system been flushed and pressure checked?
Yes No
2. Have isolation valves to the chiller been installed?
Yes No
3. Has the entire system been filled with fluid?
Yes No
4. Has air been bled from the heat exchangers and piping?
Yes No
5. Is there a minimum load of 25% of the design load?
Yes No
6. Has the water piping been insulated?
Yes No
7. Is the glycol the proper type and concentration (N/A if water)?
Yes No
8. What is the freeze point of the glycol (N/A if water)? ______________________________
Air-Cooled Condenser
Evaporative-Cooled Condenser
Low Ambient Control
Condenser Safety Check
No Water Leaks
Water Flow ________ gpm
Chilled Water In Temperature ________°F
Chilled Water Out Temperature ________°F
Check Rotation
Number
Model #
L1
L2
L3
Head
Pressure
PSIG
Suction
Pressure
PSIG
Crankcase
Heater
Amps
1 2 3 4
Chiller Configuration
Compressors/DX Cooling
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52
Pressure
Saturated
Temperature
Line
Temperature
Sub-cooling
Superheat
Discharge
N/A
N/A
Suction
N/A
Liquid
N/A
Pressure
Saturated
Temperature
Line
Temperature
Sub-cooling
Superheat
Discharge
N/A
N/A
Suction
N/A
Liquid
N/A
Alignment
Check Rotation
Nameplate Amps________
Number
hp
L1
L2
L3
1
2
3
4
5
6
hp
L1
L2
L3
Flow (gpm)
Chiller Pump #1
Chiller Pump #2
Refrigeration System 1 - Cooling Mode
Refrigeration System 2 - Cooling Mode
Condenser Fans
Pumping Package
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Maintenance Log

Entry Date
Action Taken
Name/Tel.
This log must be kept with the unit. It is the responsibility of the owner and/or maintenance/service contractor to document any service, repair or adjustments. AAON Service and Warranty Departments are available to advise and provide phone help for proper operation and replacement parts. The responsibility for proper start-up, maintenance and servicing of the equipment falls to the owner and qualified licensed technician.
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54

Literature Change History

July 2015
Initial version of document.
Page 55
Page 56
AAON
2425 South Yukon Ave.
Tulsa, OK 74107-2728
Phone: 918-583-2266
Fax: 918-583-6094
www.aaon.com
LF Series
Installation, Operation, &
Maintenance
V45070 · Rev. A · 150716
(ACP J00425)
It is the intent of AAON to provide accurate and current product information. However, in the interest of product improvement, AAON reserves the right to change pricing, specifications, and/or design of its product without notice, obligation, or liability.
Copyright © AAON, all rights reserved throughout the world.
AAON® and AAONAIRE® are registered trademarks of AAON, Inc., Tulsa, OK.
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