AAON LN-140 User Manual

LN Series

Chillers and Outdoor Mechanical Rooms

FIRE OR EXPLOSION HAZARD

Failure to follow safety warnings exactly could result in serious injury, death or property damage.

Be sure to read and understand the installation, operation and service instructions in this manual.

Improper installation, adjustment, alteration, service or maintenance can cause serious injury, death or property damage.

A copy of this IOM should be kept with the unit.

Do not store gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS

 Do not try to light any appliance.  Do not touch any electrical switch;

do not use any phone in your building.

 Leave the building immediately.  Immediately call you gas supplier

from a phone remote from the

building. Follow the gas supplier’s

instructions.

 If you cannot reach your gas

supplier call the fire department.

Startup and service must be performed by a Factory Trained Service Technician.

WARNING

Installation, Operation,

& Maintenance

Table of Contents

Safety .............................................................................................................................................. 6

LN Series Feature String Nomenclature ....................................................................................... 10

General Information ...................................................................................................................... 15

Codes and Ordinances ............................................................................................................... 15

Receiving Unit ........................................................................................................................... 15

Storage ....................................................................................................................................... 15

Chiller ........................................................................................................................................ 16

Wiring Diagrams ....................................................................................................................... 17

General Maintenance ................................................................................................................. 17

Chiller Primary Pumping .......................................................................................................... 17

Automatic Air Vent ................................................................................................................... 17

Dual Pumps ............................................................................................................................... 18

Pressure Gauges and Thermometers ......................................................................................... 18

Pipe Insulation ........................................................................................................................... 18

Installation..................................................................................................................................... 19

Chiller Placement ...................................................................................................................... 19

Curb and Steel Mount Installation ............................................................................................ 19

Lifting and Handling ................................................................................................................. 20

Water Connection ...................................................................................................................... 22

Mounting Isolation .................................................................................................................... 22

Access Doors ............................................................................................................................. 22

End Flashing Installation ........................................................................................................... 22

Low Ambient Operation ............................................................................................................ 23

Electrical .................................................................................................................................... 23

Startup ........................................................................................................................................... 25

Axial Flow Condenser Fans ...................................................................................................... 26

Maintenance .................................................................................................................................. 29

General ...................................................................................................................................... 29

Compressors .............................................................................................................................. 29

Adjusting Refrigerant Charge ................................................................................................... 29

Lubrication ................................................................................................................................ 33

Air-Cooled Condenser ............................................................................................................... 33

Brazed Plate Heat Exchanger Cleaning .................................................................................... 33

E-Coated Coil Cleaning ............................................................................................................ 33

Recommended Coil Cleaner .................................................................................................. 34

Recommended Chloride Remover ......................................................................................... 34

Microchannel Coil Cleaning ..................................................................................................... 35

Service ....................................................................................................................................... 35

Replacement Parts ..................................................................................................................... 35

AAON Warranty, Service and Parts Department ...................................................................... 35

Appendix - Water Piping Component Information ...................................................................... 36

Automatic Air Vent Valves ....................................................................................................... 36

Pumps - Installation and Operating Instructions ....................................................................... 38

Pump Piping - General .............................................................................................................. 39

Pump Operation ......................................................................................................................... 40

General Care .............................................................................................................................. 41

Dual Pump Specific Information ............................................................................................... 43

Suction Guides .......................................................................................................................... 48

Flo-Trex Combination Valve .................................................................................................... 49

LN Series Startup Form ................................................................................................................ 54

Maintenance Log .......................................................................................................................... 57

Literature Change History............................................................................................................. 58

V28980 · Rev. A · 140225

Index of Tables and Figures

Tables:

Table 1 - Service Clearances......................................................................................................... 19

Table 2 - Mounting Dimensions ................................................................................................... 20

Table 3 - Return/Exhaust Fan Pin Location .................................................................................. 27

Table 4 - Return/Exhaust Fan Pin Location .................................................................................. 27

Table 5 - Fan Assembly Bushing Torque Specifications.............................................................. 28

Table 6 - Acceptable Refrigeration Circuit Values ....................................................................... 30

Table 7 - R-410A Refrigerant Temperature-Pressure Chart ......................................................... 32

Figures:

Figure 1 - Curb Mounting with Dimensions ................................................................................. 19

Figure 2 - Steel Mounting Rail with Dimensions ......................................................................... 20

Figure 3 - Lifting Points ................................................................................................................ 20

Figure 4 - Lifting Detail of a 45-75 ton Unit ................................................................................ 21

Figure 5 - Lifting Detail of a 95-140 ton Unit .............................................................................. 21

Figure 6 - Factory Supplied End Flashings................................................................................... 22

Figure 7 - Front View of Utility Entry and Power Switch from Control Compartment ............... 23

Figure 8 - Fan with the HUB on the top and RET on the bottom. ................................................ 26

Figure 9 - Bushing Mount Location.............................................................................................. 26

Figure 10 - RET with Pin in Groove 4 .......................................................................................... 26

Figure 11 - Fan HUB and RET Castings ...................................................................................... 27

Figure 12 - Pitch Insert ................................................................................................................. 28

Safety

ELECTRIC SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.

Improper servicing could result in dangerous operation, serious injury, death, or property damage.

 Before servicing, disconnect all

electrical power to the furnace. More than one disconnect may be provided.

 When servicing controls, label all

wires prior to disconnecting. Reconnect wires correctly.

 Verify proper operation after

servicing. Secure all doors with key-lock or nut and bolt.

WARNING

Attention should be paid to the following statements:

NOTE - Notes are intended to clarify the unit installation, operation and maintenance.

CAUTION - Caution statements are given to prevent actions that may result in

equipment damage, property damage, or personal injury.

WARNING - Warning statements are given to prevent actions that could result in

equipment damage, property damage, personal injury or death.

DANGER - Danger statements are given to prevent actions that will result in equipment

damage, property damage, severe personal injury or death.

QUALIFIED INSTALLER

Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal injury or loss of life. Startup and service must be performed by a Factory Trained Service Technician. A copy of this IOM should be kept with the unit.

WARNING

WHAT TO DO IF YOU SMELL GAS

 Do not try to turn on unit.  Shut off main gas supply.  Do not touch any electric switch.  Do not use any phone in the

building.

 Never test for gas leaks with an

open flame.

 Use a gas detection soap solution

and check all gas connections and shut off valves.

CAUTION

FIRE, EXPLOSION OR CARBON MONOXIDE POISONING HAZARD

Failure to replace proper controls could result in fire, explosion or carbon monoxide poisoning. Failure to follow safety warnings exactly could result in serious injury, death or property damage. Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this appliance.

Electric shock hazard. Before servicing, shut off all electrical power to the unit, including remote disconnects, to avoid shock hazard or injury from rotating parts. Follow proper Lockout-Tagout procedures.

WARNING

VARIABLE FREQUENCY DRIVES

Do not leave VFDs unattended in hand mode or manual bypass. Damage to personnel or equipment can occur if left unattended. When in hand mode or manual bypass mode VFDs will not respond to controls or alarms.

WARNING

During installation, testing, servicing, and troubleshooting of the equipment it may be necessary to work with live electrical components. Only a qualified licensed electrician or individual properly trained in handling live electrical components shall perform these tasks.

Standard NFPA-70E, an OSHA regulation requiring an Arc Flash Boundary to be field established and marked for identification of where appropriate Personal Protective Equipment (PPE) be worn, should be followed.

WARNING

GROUNDING REQUIRED

All field installed wiring must be completed by qualified personnel. Field installed wiring must comply with NEC/CEC, local and state electrical code requirements. Failure to follow code requirements could result in serious injury or death. Provide proper unit ground in accordance with these code requirements.

WARNING

Electric motor over-current protection and overload protection may be a function of the Variable Frequency Drive to which the motors are wired. Never defeat the VFD motor overload feature. The overload ampere setting must not exceed 115% of the electric motors FLA rating as shown on the motor nameplate.

CAUTION

PVC (Polyvinyl Chloride) and CPVC (Chlorinated Polyvinyl Chloride) are vulnerable to attack by certain chemicals. Polyolester (POE) oils used with R-410A and other refrigerants, even in trace amounts, in a PVC or CPVC piping system will result in stress cracking of the piping and fittings and complete piping system failure.

CAUTION

UNIT HANDLING

To prevent injury or death lifting equipment capacity shall exceed unit weight by an adequate safety factor. Always test-lift unit not more than 24 inches high to verify proper center of gravity lift point to avoid unit damage, injury or death.

WARNING

Door compartments containing hazardous voltage or rotating parts are equipped with door latches to allow locks. Door latch are shipped with nut and bolts requiring tooled access. If you do not replace the shipping hardware with a pad lock always re-install the nut & bolt after closing the door.

CAUTION

Rotation must be checked on all MOTORS AND COMPRESSORS of 3 phase units at startup by a qualified service technician. Scroll compressors are directional and can be damaged if rotated in the wrong direction. Compressor rotation must be checked using suction and discharge gauges. Fan motor rotation should be checked for proper operation. Alterations should only be made at the unit power connection

CAUTION

Do not use oxygen, acetylene or air in place of refrigerant and dry nitrogen for leak testing. A violent explosion may result causing injury or death.

WARNING

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

CAUTION

Some chemical coil cleaning compounds are caustic or toxic. Use these substances only in accordance with the manufacturer’s usage instructions. Failure to follow instructions may result in equipment damage, injury or death.

WARNING

Do not clean DX refrigerant coils with hot water or steam. The use of hot water or steam on refrigerant coils will cause high pressure inside the coil tubing and damage to the coil.

CAUTION

Polyolester (POE) and Polyvinylether (PVE) oils are two types of lubricants used in hydrofluorocarbon (HFC) refrigeration systems. Refer to the compressor label for the proper compressor lubricant type.

CAUTION

COMPRESSOR CYCLING

5 MINUTE MINIMUM OFF TIME To prevent motor overheating compressors must cycle off for a minimum of 5 minutes.

5 MINUTE MINIMUM ON TIME To maintain the proper oil level compressors must cycle on for a minimum of 5 minutes.

The cycle rate must not exceed 6 starts per hour.

WARNING

1. Startup and service must be performed

by a Factory Trained Service Technician

2. The unit is for outdoor use only. See

General Information section for more information.

3. Every unit has a unique equipment

nameplate with electrical, operational, and unit clearance specifications. Always refer to the unit nameplate for specific ratings unique to the model you have purchased.

4. READ THE ENTIRE INSTALLATION,

OPERATION AND MAINTENANCE MANUAL. OTHER IMPORTANT SAFETY PRECAUTIONS ARE

PROVIDED THROUGHOUT THIS MANUAL.

5. Keep this manual and all literature

safeguarded near or on the unit.

LN Series Feature String Nomenclature

Model Options

Unit Feature Options

GEN

MJREV

SIZE SERIES MNREV

VLT A1

5D 6

7 8A

8C 9 10A

10B

10C

10D

LN A – 140 – C – 0 – 3 – C A C 0 E – 0 0 0 0 : A 0 – 0 0 0 0 – 0 0 0 0 – 0 0 0 0 – 0 0 – 0 0 0 – 0 – 0 E 0 0 –

0 0 0 0 0 – 0 A 0 0 0 – 0 0 0 0 0 – 0 0 0 0 0 0 – 0 0 0 0 0 – 0 0 0 B

26A

26B

26C

26D

26E

26F

MODEL OPTIONS

SERIES AND GENERATION

MAJOR REVISION

UNIT SIZE

045 = 45 ton Capacity 055 = 55 ton Capacity 060 = 60 ton Capacity 075 = 75 ton Capacity 095 = 95 ton Capacity 105 = 105 ton Capacity 120 = 120 ton Capacity 140 = 140 ton Capacity

SERIES

A = 45-60 ton units B = 75 ton unit C = 95-140 ton units

MINOR REVISION

VOLTAGE

2 = 230V/3Φ/60Hz 3 = 460V/3Φ/60Hz 4 = 575V/3Φ/60Hz 8 = 208V/3Φ/60Hz

A1: COMPRESSOR STYLE

C = R-410A Tandem VFD Compatible Scroll Compressor

A2: CONDENSER STYLE

A = Air-Cooled Microchannel Condenser

A3: EVAPORATOR CONFIGURATION

A = Standard Brazed Plate Constant Flow B = Oversized Brazed Plate Constant Flow C = Standard Shell & Tube Constant Flow D = Oversized Shell & Tube Constant Flow

A4: COATING

0 = Standard E = Polymer E-Coated Condenser Coil

A5: STAGING

0 = Staged Compressors E = All Circuits with Variable Capacity Compressors

- 2 Circuits G = Half Circuits with Variable Capacity Compressors - 2 Circuits

B1: BLANK

0 = Standard

B2: BLANK

0 = Standard

B3: BLANK

0 = Standard

B4: BLANK

0 = Standard

UNIT FEATURE OPTIONS

1: UNIT ORIENTATION

A = Standard Access Left Water Connections B = Standard Access Right Water Connections C = Standard Access Bottom Water Connections

2: PUMPING STYLE

0 = No Pumps B = Constant Flow Primary Pumping System - Large Pipe Size D = Variable Flow Primary Pumping System - Large Pipe Size

LN Series Feature String Nomenclature

Model Options

Unit Feature Options

GEN

MJREV

SIZE SERIES

MNREV VLT

B4 1 2

5D 6 7 8A

8C 9

10A

10B

10C

10D

LN A – 140 – C – 0 – 3 – C A C 0 E – 0 0 0 0 : A 0 – 0 0 0 0 – 0 0 0 0 – 0 0 0 0 – 0 0 – 0 0 0 – 0 – 0 E 0 0 –

0 0 0 0 0 – 0 A 0 0 0 – 0 0 0 0 0 – 0 0 0 0 0 0 – 0 0 0 0 0 – 0 0 0 B

26A

26B

26C

26D

26E

26F

3A: BUILDING PUMP CONFIGURATION

0 = No Building Pumps A = 1 Pump + High Eff Motor B = 1 Dual Pump + High Eff Motors D = 1 Pump + VFD + High Eff Motor E = 1 Dual Pump + 2 VFD's + High Eff Motors K = 1 Pump + Field Installed VFD + High Eff Motor L = 1 Dual Pump + 2 Field Installed VFD's + High Eff Motors

3B: BUILDING PUMP SERIES AND RPM

0 = No Building Pumps A = 4360 (1,170 nominal rpm) B = 4360 (1,760 nominal rpm) C = 4360 (3,520 nominal rpm) D = 4380 (1,170 nominal rpm) E = 4380 (1,760 nominal rpm) F = 4380 (3,520 nominal rpm) K = 4382 (1,170 nominal rpm) L = 4382 (1,760 nominal rpm) M = 4382 (3,520 nominal rpm)

3C: PUMP SIZE

0 = No Building Pumps A = 1.5B B = 2B C = 2D D = 3D E = 1.5x1.5x6 F = 2x2x6 G = 3x3x6 H = 4x4x6 J = 6x6x6 K = 1.5x1.5x8 L = 2x2x8 M = 3x3x8 N = 4x4x8 P= 5x5x8 Q = 6x6x8 R = 8x8x8 S = 2x2x10 T = 3x3x10 U = 4x4x10 V = 6x6x10 W = 8x8x10 Y = 4x4x11.5 Z = 5x5x11.5 1 = 6x6x11.5 2 = 8x8x11.5 3 = 4x4x13 4 = 6x6x13 5 = 8x8x13

LN Series Feature String Nomenclature

GEN

MJREV

SIZE SERIES

MNREV VLT

B4 1 2 3A

3D 4A

5D 6 7

9 10A

10B

10C

10D

LN A – 140 – C – 0 – 3 – C A C 0 E – 0 0 0 0 : A 0 – 0 0 0 0 – 0 0 0 0 – 0 0 0 0 – 0 0 – 0 0 0 – 0 – 0 E 0 0

–

0 0 0 0 0 – 0 A 0 0 0 – 0 0 0 0 0 – 0 0 0 0 0 0 – 0 0 0 0 0 – 0 0 0 B

26A

26B

26C

26D

26E

26F

Model Options

Unit Feature Options

3D: BUILDING PUMP MOTOR SIZE

0 = No Building Pumps C = 1 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

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 = Standard A = Hot Gas Bypass on Non-Variable Capacity Circuits B = Hot Gas Bypass - All Circuits

7: REFRIGERATION ACCESSORIES

0 = Standard A = Sight Glass B = Compressor Isolation Valves C = Option A + B

8A: UNIT DISCONNECT TYPE

0 = Standard Single Point Power Block A = Single Point Power Non-fused Disconnect

8B: DISCONNECT SIZE

0 = Power Block N = 100 amps R = 150 amps U = 225 amps Z = 400 amps 3 = 600 amps 5 = 800 amps 7 = 1200 amps

8C: BLANK

0 = Standard

9: ACCESSORIES

0 = Standard B = Phase & Brown Out Protection

10A: UNIT CONTROL SEQUENCE

0 = Standard Controls

10B: UNIT CONTROL SUPPLIER

E = MCS Controls

10C: CONTROL SUPPLIER OPTIONS

0 = Standard A = Touchscreen Interface C = Modem G = Option A + C

LN Series Feature String Nomenclature

Model Options

Unit Feature Options

GEN

MJREV

SIZE SERIES

MNREV VLT

B4 1 2

5D 6 7 8A

8C 9

10A

10B

10C

10D

LN A – 140 – C – 0 – 3 – C A C 0 E – 0 0 0 0 : A 0 – 0 0 0 0 – 0 0 0 0 – 0 0 0 0 – 0 0 – 0 0 0 – 0 – 0 E 0 0 –

0 0 0 0 0 – 0 A 0 0 0 – 0 0 0 0 0 – 0 0 0 0 0 0 – 0 0 0 0 0 – 0 0 0 B

26A

26B

26C

26D

26E

26F

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 = Standard C = Vestibule Heating (Electric)

13: MAINTENANCE ACCESSORIES

0 = Standard A = 115VAC Convenience Outlet Factory Wired B = 115VAC Convenience Outlet Field Wired C = Service Lights F = Options A + C J = Options B + C

14: BLANK

0 = Standard

15: CODE OPTIONS

0 = Standard ETL U.S.A. Listing A = Chicago Code B = ETL U.S.A. + Canada Listing

16: SHIPPING SPLITS

0 = One Piece Unit

17: AIR-COOLED CONDENSER ACCESSORIES

H = Cond Coil Guards + Three Phase Cond Fan Motor + Fan Cycling- 35°F Low Ambient J = Cond Coil Guards + VFD Cond Fan Head Pressure Control - 0°F Low Ambient

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 = Standard 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

LN Series Feature String Nomenclature

Model Options

Unit Feature Options

GEN

MJREV

SIZE SERIES

MNREV VLT

B4 1 2

5D 6 7 8A

8C 9

10A

10B

10C

10D

LN A – 140 – C – 0 – 3 – C A C 0 E – 0 0 0 0 : A 0 – 0 0 0 0 – 0 0 0 0 – 0 0 0 0 – 0 0 – 0 0 0 – 0 – 0 E 0 0 –

0 0 0 0 0 – 0 A 0 0 0 – 0 0 0 0 0 – 0 0 0 0 0 0 – 0 0 0 0 0 – 0 0 0 B

26A

26B

26C

26D

26E

26F

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

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 = Premium AAON Gray Paint Exterior + Shrink Wrap X = Special Pricing Authorization + Premium AAON Gray Paint Exterior 1 = SPA + Premium AAON Gray Paint Exterior + Shrink Wrap 4 = Special Pricing Authorization + Special Exterior Paint Color 7 = SPA + Special Exterior Paint Color + Shrink Wrap

General Information

WARNING

The Clean Air Act of 1990 bans the intentional venting of refrigerant as of July 1, 1992. Approved methods of recovery, recycling, or reclaiming must be followed.

CAUTION

Coils and sheet metal surfaces present sharp edges and care must be taken when working with equipment.

Failure to observe the following instructions will result in premature failure of your system and possible voiding of the warranty.

WARNING

AAON LN Series chillers are complete selfcontained liquid chilling units. They are assembled, wired, charged and run-tested. Models are available for air-cooled applications. Chiller primary pumping packages are available as optional features.

Codes and Ordinances

LN Series units have been tested and certified, by ETL, in accordance with UL Safety Standard 1995/CSA C22.2 No. 236.

System should be sized in accordance with the American Society of Heating, Refrigeration and Air Conditioning Engineers Handbook.

Installation of LN 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.

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.

Storage

If installation will not occur immediately following delivery, store equipment in a dry protected area away from construction traffic and in the proper orientation as marked on the packaging with all internal packaging in place. Secure all loose-shipped items.

Chiller

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.

CRANKCASE HEATER

OPERATION Units may be 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.

CAUTION

COMPRESSOR CYCLING

5 MINUTE MINIMUM OFF TIME To prevent motor overheating compressors must cycle off for a minimum of 5 minutes.

5 MINUTE MINIMUM ON TIME To maintain the proper oil level compressors must cycle on for a minimum of 5 minutes.

The cycle rate must not exceed 6 starts per hour.

WARNING

Failure to observe the following instructions will result in premature failure of your system, and possible voiding of the warranty.

Never turn 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. The compressor is designed to pump refrigerant gas and damage may occur

when power is restored if liquid enters the compressor.

Before unit operation, the main power switch must be turned on for at least 24 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.

Never cut off the main power supply to the unit, except for complete shutdown. Always control the system from the building management system, or control panel, never at the main power supply (except for emergency or for complete shutdown of the system).

Scroll compressors must be on a minimum of 5 minutes and off for a minimum of 5 minutes. The cycle rate must be no more than 6 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.

Compressor life will be seriously shortened by reduced lubrication, and the pumping of excessive amounts of liquid oil and liquid refrigerant.

Wiring Diagrams

A complete set of unit specific wiring diagrams in both ladder and point-to-point form are laminated in plastic and located inside the control compartment door.

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. See the air-cooled condenser sections in this manual for specific details.

Chiller Primary Pumping

Primary pumping uses a single pump to move water (or glycol) through the chiller barrel and back to the building. This pumping package provides a constant 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 separator 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 setpoint, 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 tube or brazed plate evaporator, leaves the unit through the water out connection.

Automatic Air Vent

There is an automatic air vent installed at the high point of the system inside the pumping package compartment. The air vent valve must be in the proper position for operation. Ensure that the small vent cap is loosened 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, factory installed dual pumps can be ordered. A dual pump is a pump with two independent motors and pumps in a single casing. This dual pump has a swing splitflapper 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. See appendix for additional information.

Pressure Gauges and Thermometers

Pressure gauges and thermometers are available as a factory installed option. Thermometers are installed on the inlet and outlet of the unit. One 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 point and close the other two needle valves. One gauge is used so that the calibration of the pressure gauge is irrelevant in the calculation of the differential pressure.

Pipe Insulation

The water piping and components on units with pumping packages are not insulated at the factory. Insulation should be installed on the water piping after the system has been checked for leaks.

Installation

Location

Unit Size

45-140 tons

Front -

(Controls Side)

72”

Back

72”

Ends

96”

Top

Unobstructed

All roofing work should be performed by competent roofing contractors to avoid any possible leakage.

CAUTION

Chiller Placement

The AAON LN Series 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.

The placement relative to the building air intakes and other structures must be carefully selected. Be sure to observe the dimensions that are on the rating plate of the chiller for operational and service clearances.

Table 1 - Service Clearances

Condenser coils and fans must be free of any obstructions in order to start and operate properly with a correct amount of airflow. 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.

Curb and Steel Mount Installation

Make openings in the roof decking large enough to allow for water piping, electrical penetrations, and workspace only. Do not make openings larger than necessary. Set the curb to coincide with the openings. Make sure curb is level.

Unit specific curb drawing is included with job submittal. See SMACNA Architectural Sheet Metal Manual for curb installation details.

Units require rail support along all four sides of the unit base.

When installed at ground level, a one-piece concrete slab should be used with footings that extend below the frost line. Care must also be taken to protect the coil and fins from damage due to vandalism or other causes.

If unit is elevated a field supplied catwalk is recommended to allow access to unit service doors.

This unit ships with a curb gasket that is

1¼” wide and 1½” tall. It is recommended

that this or another similar gasket be used between the curb and the unit to reduce vibration from the unit to the building.

Figure 1 - Curb Mounting with Dimensions

Figure 2 - Steel Mounting Rail with

Tons

A B C

45-140

142”

138”

134”

139”

Dimensions

Table 2 - Mounting Dimensions

Lifting and Handling

If cables or chains are used to hoist the unit they must be the same length and care should be taken to prevent damage to the cabinet. See Figure 4 for additional information.

Before lifting unit, be sure that all shipping material has been removed from unit. Secure hooks and cables at all lifting points/ lugs provided on the unit.

Hoist unit to a point directly above the curb or mounting rail. Be sure that the gasket material has been applied to the curb or mounting rail.

Carefully lower and align unit with utility and duct openings. Lower the unit until the unit skirt fits around the curb. Make sure the unit is properly seated on the curb and is level.

Do not push, pull or lift the unit from anything other than its base.

Figure 3 - Lifting Points

Figure 4 - Lifting Detail of a 45-75 ton Unit

Figure 5 - Lifting Detail of a 95-140 ton Unit

Lifting slot locations are unit specific.

Unit must be rigged at all marked lifting points.

Water Connection

CAUTION

The chiller must be operated only with liquid flowing through the evaporators.

WARNING

In order to prevent water leakage into the roof curb, the factory provided sheet metal flashings MUST BE attached to the unit base to cover the shipping slots at both ends of the unit.

CAUTION

Installing Contractor is responsible for proper sealing of the water piping entries into the unit Failure to seal the entries may result in damage to the unit and property.

CAUTION

Connect the 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 AAON LN Series units is 125 psi.

Mounting Isolation

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

Access Doors

Lockable access door is provided to the compressor and control compartment. A

separate access door is also provided to the pumping package compartment.

A light switch with service lights is provided on the wall of the compressor and control compartment.

End Flashing Installation

On all LN Series units the cabinet width will overhang the shipping trailer on each side.

In order to secure and protect the unit during transit the sheet metal end flashings have been removed from the unit. The slot created at the base of each end of the unit allows the unit to set firmly on the trailer deck.

Sheet metal flashings are shipped loose with the unit and once the unit is set into place the flashings must be installed on each end of the unit to complete the finished seal at the base. The flashings are unit specific and designed to cover the slot at each end of the unit to prevent water run-off into the curb.

Failure to attach and seal the end of unit with the flashings may result in water leakage into the curb.

Figure 6 - Factory Supplied End Flashings

Low Ambient Operation

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, death, or property damage.

WARNING

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.

CAUTION

If the chiller is ordered for a Low Ambient application, the liquid system must use a glycol solution and the piping must be insulated to be prepared for freezing conditions. Care must be taken in the source of electrical power for the heating tape and thermostat.

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 outdoor mechanical room.

Verify the unit nameplate voltage agrees with the power supply. Connect power and control field wiring as shown on the unit specific wiring diagram provided with the unit.

Size supply conductors based on the unit MCA rating. Supply conductors must be rated a minimum of 167°F (75°C).

Route power and control wiring, separately, through the utility entry. Do not run power and signal wires in the same conduit.

Protect the branch circuit in accordance with code requirements. The unit 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.

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 unit's agency/safety certification.

Figure 7 - Front View of Utility Entry and Power Switch from Control Compartment

Startup technician must check for proper motor rotation and check fan motor amperage listed on the motor nameplate is not exceeded. Motor overload protection

may be a function of the variable frequency

Rotation must be checked on all MOTORS AND COMPRESSORS of three phase units. 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. Variable frequency drives are programmed to automatically rotate the fan in the correct rotation. Do not rely on fans with variable frequency drives for compressor rotation.

CAUTION

drive and must not be bypassed.

Note: All units are factory wired for 208/230V, 460V, or 575V. If unit is to be connected to a 208V supply, the transformer must be rewired to 208V service. For 208V service interchange the yellow and red conductor on the low voltage control transformer. Red-Black for 208V Yellow-Black for 230V

Wire control signals to the unit’s low

voltage terminal block located in the controls compartment.

If any factory installed wiring must be replaced, use a minimum 221°F (105°C) type AWM insulated conductors.

Startup

Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.

WARNING

Improper installation, adjustment, alteration, service, or maintenance can cause property damage, personal injury, or loss of life. Startup and service must be performed by a Factory Trained Service Technician

WARNING

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.

CAUTION

Before completing installation, a complete operating cycle should be observed to verify that all components are functioning properly.

(See back of the manual for startup form)

Before the startup of the chiller be 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 MCS 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 compressor 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 chiller.

Axial Flow Condenser Fans

Bushing Mount

Bushing

Mount

Bushing

Multi-Wing Z Series Aluminum Fan Blade Pitch Angle Setting Instructions

1. Maintain the balance of fan Mark the hub castings across a joint, so the fan hub can be reassembled in the same orientation.

Mark the location of any balancing weight. Balancing weight will be on the outer bolt circle, in the form of washers, and/or longer bolts, or an additional balancing nut.

Number the blades and blade sockets, so that they are replaced into their original position.

Location A is with the bushing mount on air inlet side of the fan. Location B is with the bushing mount on air discharge side of the fan.

Figure 9 - Bushing Mount Location

4. Determine the pin location groove

Disassemble fan on a flat surface and note in which groove the pin is located.

Figure 8 - Fan with the HUB on the top and

RET on the bottom.

2. Determine the direction of rotation

Right, R, is clockwise when facing the discharge side of the fan and Left, L, is counterclockwise when facing the discharge side of the fan.

3. Determine the bushing mount location

The bushing mount is the center section of the hub through which the fan is mounted to the shaft, and typically contains either setscrews or a center-tapered hole where the bushing inserts.

Figure 10 - RET with Pin in Groove 4

5. Determine whether the pin is in the HUB

Type

Bushing

Mount

Blade Pitch Angle

20°

25°

28°

30°

33°

35°

38°

40°

45°

50°

RET

HUB

HUB B -

HUB

RET

Type

Rot.

Blade Pitch Angle

20°

25°

28°

30°

33°

35°

38°

40°

45°

50°

R - 4 - 3 2 1 4 3 2 1 L - 1 - 2 3 4 1 2 3

or RET

Figure 11 - Fan HUB and RET Castings

6. Determine the current blade pitch and the pin location for the new blades

Table 3 - Return/Exhaust Fan Pin Location

Table 4 - Return/Exhaust Fan Pin Location

7. Replace fan blades in the new pin

location and reassemble the fan

Replace the blades with the pin in the 1, 2, 3, or 4 groove position of either the HUB or RET. Assemble the fan making sure to place the blades in their previous blade sockets, to match up the previous orientation of HUB and RET and to replace any balancing

weights in their previous locations. Tighten bolts in a cross pattern to 5-6 ft-lbs. of torque.

Multi-Wing W Series Black Glass

Bushing

Tightening Torque

(in-lbs.)

H X 1.125"

H X 1.375"

SH X 1.125"

108

SH X 1.375"

108

SD X 1.125"

108

SD X 1.375"

108

SD X 1.625"

108

SD X 1.875"

108

SK X 2.125"

180

Reinforced Polypropylene Fan Blade Pitch Angle Setting Instructions

Contact the AAON parts department to acquire the new pitch pins for the fan blades.

Note original position of retaining plates, center boss and all hardware including additional hardware used for balancing.

1. Remove all the bolts and nuts.

2. Determine blade rotation – on the concave side of the blade is a blade marking showing 6WR, 6WL, 7WL, 7WR, or 9WR.

The “L” and “R” denote the rotation of the

blade.

3. Replace the pitch insert in the blade root with an insert of the desired pitch.

Figure 12 - Pitch Insert

4. Replace blades to their original location.

5. Replace all nuts, bolts, and washers on the fan hub.

6. Replace retaining plates and center boss to original location.

7. Tighten nuts and bolts to 14 ft-lbs of torque.

Fan Assembly Bushings

The fan assembly bushings should be tightened to the specifications listed in the following table.

Table 5 - Fan Assembly Bushing Torque

Specifications

Maintenance

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.

CAUTION

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.

Air-cooled condenser units require maintenance schedules/procedures. Unit specific instructions are included in this manual.

Compressors

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

Adjusting Refrigerant Charge

All AAON chillers are shipped with a full factory charge. Periodically adjusting the charge of a system may be required.

Adjusting the charge of a system in the field must be based on determination of liquid sub-cooling and evaporator superheat. On a system with an 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.

Units equipped with hot gas bypass must have the hot gas bypass valve closed to get the proper 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 6 when determining the proper sub-cooling.

For units equipped with low ambient (0°F) option see the special charging instructions at the end of this section.

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

Air-Cooled Condenser with Scroll Compressors

Sub-Cooling

12-18°F

Superheat

10-15°F

Expansion valves must be adjusted to approximately 10-15°F of suction superheat. Failure to have sufficient superheat will damage the compressor and void the warranty.

CAUTION

DO NOT OVERCHARGE!

Refrigerant overcharging leads to excess refrigerant in the condenser coils resulting in elevated compressor discharge pressure.

CAUTION

temperature using the appropriate refrigerant temperature-pressure chart.

Subtract the measured liquid line temperature from the saturated temperature 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 scroll compressors, it is critical that the suction superheat setpoint on the expansion valve is set with one compressor running. The suction superheat should be 10-13°F with one compressor running. The suction superheat 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 6 for the appropriate unit type and options.

Table 6 - Acceptable Refrigeration Circuit

Values

One compressor running in tandem

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 6 (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.

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 expansion valve may need adjustment to correct the superheat.

Table 7 - R-410A Refrigerant Temperature-Pressure Chart

psig F psig F psig F psig F psig

78.3

142.2

234.9

110

364.1

140

540.1

80.0

144.8

238.6

111

369.1

141

547.0

81.8

147.4

242.3

112

374.2

142

553.9

83.6

150.1

246.0

113

379.4

143

560.9

85.4

152.8

249.8

114

384.6

144

567.9

87.2

155.5

253.7

115

389.9

145

575.1

89.1

158.2

257.5

116

395.2

146

582.3

91.0

161.0

261.4

117

400.5

147

589.6

92.9

163.8

265.4

118

405.9

148

596.9

94.9

166.7

269.4

119

411.4

149

604.4

96.8

169.6

273.5

120

416.9

150

611.9

98.8

172.5

277.6

121

422.5

100.9

175.4

281.7

122

428.2

102.9

178.4

285.9

123

433.9

105.0

181.5

290.1

124

439.6

107.1

184.5

294.4

125

445.4

109.2

187.6

298.7

126

451.3

111.4

190.7

303.0

127

457.3

113.6

193.9

307.5

128

463.2

115.8

197.1

311.9

129

469.3

118.1

200.4

100

316.4

130

475.4

120.3

203.6

101

321.0

131

481.6

122.7

207.0

102

325.6

132

487.8

125.0

210.3

103

330.2

133

494.1

127.4

213.7

104

334.9

134

500.5

129.8

217.1

105

339.6

135

506.9

132.2

220.6

106

344.4

136

513.4

134.7

224.1

107

349.3

137

520.0

137.2

227.7

108

354.2

138

526.6

139.7

231.3

109

359.1

139

533.3

Lubrication

Electric shock hazard. Shut off all electrical power to the unit to avoid shock hazard or injury from rotating parts.

WARNING

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.

Air-Cooled Condenser

The air-cooled condenser section rejects heat by passing outdoor air over the fin tube 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 according to the microchannel coil cleaning section.

Brazed Plate Heat Exchanger Cleaning

Because of a normally high degree of turbulence in brazed plate heat exchangers, for many applications the heat exchanger channels are self-cleaning. For applications that are not self-cleaning (i.e. hard water at high temperatures, etc.) or applications where additional cleaning is desired, it is possible to clean the brazed plate heat exchanger by circulating a cleaning liquid.

Use a tank with weak acid, 5% phosphoric acid (H3PO4) or, if the exchanger is frequently cleaned, 5% oxalic acid

(H2C2O4). Pump the cleaning liquid through the exchanger. For optimum cleaning, the cleaning solution flow rate should be a minimum of 1.5 times the normal flow rate, preferably in a back-flush mode. After cleaning, the heat exchanger must be rinsed with clean water. A solution of 1-2% sodium hydroxide (NaOH) or sodium bicarbonate (NaHCO) before the last rinse ensures that all acid is neutralized.

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

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.

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

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 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.

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 below 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 themselves to the substrate. For the effective use of this product, the product must be able to come 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. As in all surface preparation, the best work yields the best results.

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

Batch-loading chemicals into the unit is NOT PERMITTED. The control system must regulate the chemical feed.

WARNING

Detergents or coil cleaners are not recommended with microchannel condenser coils. 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

the substrate has been thoroughly wetted, the salts will be soluble and is now only necessary to rinse them off.

Rinse - It is highly recommended that a hose be used, as a pressure washer 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 Documented routine cleaning of microchannel coils with factory provided ecoating is required to maintain coating warranty coverage. See E-Coated Coil Cleaning section.

Air-cooled heat exchangers may include microchannel coils. Only clean water is recommended for cleaning microchannel coils. 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.

Only clean water is recommended for cleaning microchannel coils. However, if solutions are mandatory to clean the unit, a cleaning solution with a pH between 5 and 9 that does not contain chlorides, sulfates, copper, iron, nickel, or titanium is required.

Field installed coil coatings are not recommended with microchannels.

Service

If the unit will not operate correctly and a service company is required, only a company with service technicians qualified and experienced in both refrigerant chillers and air conditioning are permitted to service the systems to keep warranties in effect. If assistance is required, the service technician must contact AAON.

Replacement Parts

Parts for AAON equipment may be obtained from your local AAON representative. When ordering parts reference the unit serial number and part number.

AAON Warranty, Service and Parts Department

2424 S. Yukon Ave. Tulsa, OK 74107 Ph: 918-583-2266 Fax: 918-382-6364 www.aaon.com

Note: Before calling, technician should have model and serial number of the unit available for the service department to help answer questions regarding the unit

Appendix - Water Piping Component Information

Automatic Air Vent Valves

Automatic Air Vent Valves provide automatic air venting for hot or cold water distribution systems. These vents purge air that may be in the water system.

The vent valve utilizes a float to actuate the valve plug which is located at the top of the valve. Once the air is displaced and the system pressure is sustained, the valve plug seals and prevents any water from escaping from the system.

The float vent can also operate as an antivacuum device since it will permit air to enter the system when it must be drained. It can also be installed to permit the separation and dispersal of air while fluid is actually circulating in the system.

Overview

 Body and cover are brass construction.  Air vent with silicone rubber seal.  Impurities do not usually affect function

as maximum float line of water is always lower than the valve seal.

 Float is high temperature resistant

polyethylene.

 Suitable for use with glycol systems.  Can be disassembled for inspection and

cleaning.

Operating Range:

Minimum working pressure: 1.45psi (10 kPa) Maximum working pressure: 150psi (10 bars) Temperature Range: 33°F – 240°F (5°C – 116°C)

Performance

Performance curve details the quantity of air

vented by the “Float Vent” according to the

pressure in the system.

Note: In order to get the best results in

venting air from risers, use connecting pipes

of at least 1⁄2" diameter between the “Float

Vent” valves and installation.

Installation

When the air vent valve is installed as shown, the air will not be vented while the fluid is circulating in the system, but it can vent when the system is shut off.

The figure below shows the installation of the vent valve for the venting of air while the fluid is circulating in the system and the required increase in pipe size in order to obtain proper separation of air from water.

The valve should be mounted only in a vertical position as its operation is based on the vertical movement of the float.

While the air vent valve is in operation, back off the small vent cap two turns. This is the proper operating setting which will allow air to be vented from the system. It is advisable to leave the cap on to prevent impurities from entering the valve.

Maintenance

No maintenance is normally necessary. However, if the FV-4M1 is disassembled for inspection or cleaning it is important that when re-assembling to ensure that the spring loaded lever properly engages under the float collar

Dimensions – Weights:

No Installation of this equipment should take place unless this document has been read and understood.

CAUTION

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.

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 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

Discharge valve only is to be used to throttle pump flow.

Use Caution. Piping may carry high temperature fluid.

CAUTION

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.

Pump Piping - General

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

Do not run pumps with discharge valve closed or under very low flow conditions.

CAUTION

Check rotation arrow prior to operating the unit.

CAUTION

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.

Pump Operation

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.

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.

‘Bump’ or energize the motor momentarily and check 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 ‘cracked’ or open 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 (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 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

Electric shock hazard. Before attempting to perform any service or maintenance on pumping unit, disconnect power source to the driver, LOCK IT OFF and tag with the reason.

WARNING

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.

Large Series split-coupled units are installed with a shaft bushing located beneath the impeller that is lubricated from the pump discharge. This bearing is field removable for service on the 20x20x19 size without disturbing the motor or other major pump components.

Motor 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/vented to the suction on close coupled pumps.

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 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

Double Check Prior to Startup

CAUTION

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 all detrimental to the pump internals and sealing arrangement.

Proper operation cannot be guaranteed if the above conditions are not adhered to.

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.

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 following 3”, 4” & 6” valve illustration and the 8” valve illustration.

Discharge Valve

Care should be taken when performing procedures 3 and 4. Read instructions carefully.

WARNING

This valve performs the dual function of automatically sealing the discharge of the 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 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.

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

2. Close these valves once the pressure is

equalized and air removed.

3. Loosen set screw (11) and lower locking

handle (3) to the horizontal position, secure with set screw (11).

4. Rotate valve to center position so that

the center pin of the locking arm (4) locates in the recess on the locking handle (3).

5. 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.

Locking

Care should be taken when performing procedures 3 and 4. Read instructions carefully.

WARNING

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.

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.

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

Table A1. Armgrip Flange Adapter Details

Valve Size

125 psi/150 psi

250 psi/300 psi

Ductile Iron Bolt

No.

Size

No.

Size

2-1/2

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

3/4 8 8

3/4

7/8

16 1 12

7/8

1-1/8

left in place. This will be detrimental to the operation of the pump.

Inspect the cover O-ring and replace if necessary.

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 anti-rotation 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

Safety glasses should be worn. Probes should not be left inserted into fittings for long periods of time as leakage may result.

CAUTION

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).

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.

Recommended Bolt Tightening Procedure

Field Conversion (Straight to Angle Pattern Valve:

1. Open valve at least one complete turn.

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,

Valve Size

2-1/2

3 4 5 6 8

Number of

Rings

5 5 6 9 10

28 (valve fully

open)

100

34) x (400

100

34) x (25.2

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.

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 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 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 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

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 USgpm

=8.57 L/s

Note: To prevent premature valve failure

Safety glasses should be worn.

CAUTION

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 free of buildup of 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.

‘’

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.

Pressure-Temperature Limits

Flo-Trex Cross Section

1. Body Main

2. Eye Bolt

3. Shaft

4. Spring

5. Spacer

6. Disc

7. Seat

8. O ring body

9. Body Suction

10. Capscrew

12. O ring

13. Bonnet

14. Sleeve

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

LN Series Startup Form

Ambient Temperature

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 50% 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

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 #

Head

Pressure

PSIG

Suction

Pressure

PSIG

Crankcase

Heater

Amps

1 2 3 4

Pressure

Saturated

Temperature

Line

Temperature

Sub-cooling

Superheat

Discharge

N/A

Suction

N/A

Liquid

N/A

Pressure

Saturated

Temperature

Line

Temperature

Sub-cooling

Superheat

Discharge

N/A

Suction

N/A

Liquid

N/A

Chiller Configuration

Compressors/DX Cooling

Refrigeration System 1 - Cooling Mode

Refrigeration System 2 - Cooling Mode

Condenser Fans

Alignment

Check Rotation

Nameplate Amps________

Number

Flow (gpm)

Chiller Building Pump #1

Chiller Building Pump #2

Pumping Package

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.

Literature Change History

February 2014

Initial version.

AAON

2425 South Yukon Ave.

Tulsa, OK 74107-2728

Phone: 918-583-2266

Fax: 918-583-6094

www.aaon.com

LN Series

Installation, Operation, &

Maintenance

V28980 · Rev. A · 140225

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.

AAON® and AAONAIRE

are registered trademarks of AAON, Inc., Tulsa, OK.

AAON LN-140 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Safety

LN Series Feature String Nomenclature

General Information

Codes and Ordinances

Receiving Unit

Storage

Chiller

Wiring Diagrams

General Maintenance

Chiller Primary Pumping

Automatic Air Vent

Dual Pumps

Pressure Gauges and Thermometers

Pipe Insulation

Installation

Chiller Placement

Curb and Steel Mount Installation

Lifting and Handling

Water Connection

Mounting Isolation

Access Doors

End Flashing Installation

Low Ambient Operation

Electrical

Startup

Axial Flow Condenser Fans

Maintenance

General

Compressors

Adjusting Refrigerant Charge

Lubrication

Air-Cooled Condenser

Brazed Plate Heat Exchanger Cleaning

E-Coated Coil Cleaning

Recommended Coil Cleaner

Recommended Chloride Remover

Microchannel Coil Cleaning Documented routine cleaning of microchannel coils with factory provided e­coating is required to maintain coating warranty coverage. See E-Coated Coil Cleaning section.

Service

Replacement Parts

AAON Warranty, Service and Parts Department

Appendix - Water Piping Component Information

Automatic Air Vent Valves

Pumps - Installation and Operating Instructions

Pump Piping - General

Pump Operation

General Care

Dual Pump Specific Information

Suction Guides

Flo-Trex Combination Valve

LN Series Startup Form

Maintenance Log

Literature Change History

Microchannel Coil Cleaning Documented routine cleaning of microchannel coils with factory provided ecoating is required to maintain coating warranty coverage. See E-Coated Coil Cleaning section.