Aaon LL-035 Installation Manual

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LL Series

Chillers and Outdoor Mechanical Rooms

Failure to follow safety warnings

installation, operation and service

, adjustment, alteration, service or maintenance can cause serious injury, death or

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

do not use any phone in your

from a phone remote from the

If you cannot reach your gas

and service must be

by a Factory Trained

WARNING

Installation, Operation

& Maintenance

FIRE OR EXPLOSION HAZARD

exactly could result in serious injury, death or property damage.

Be sure to read and understand the

instructions in this manual.

Improper installation

property damage.

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;

building.

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

building. Follow the gas supplier’s instructions.



supplier call the fire department.

Startup performed Service Technician.

Table of Contents

Safety .............................................................................................................................................. 7

LL Series Feature String Nomenclature ....................................................................................... 11

General Information ...................................................................................................................... 19

Codes and Ordinances ............................................................................................................... 19

Receiving Unit ........................................................................................................................... 19

Storage ....................................................................................................................................... 19

Outdoor Mechanical Room ....................................................................................................... 20

Wiring Diagrams ....................................................................................................................... 21

General Maintenance ................................................................................................................. 21

Chiller Primary Pumping .......................................................................................................... 21

Chiller Primary/Secondary Pumping ........................................................................................ 21

Boiler System ............................................................................................................................ 22

Boiler Primary/Secondary Pumping .......................................................................................... 22

Make Up Water ......................................................................................................................... 23

Compression/Expansion Tank ................................................................................................... 23

Pressure Relief Valve ................................................................................................................ 24

Automatic Air Vent ................................................................................................................... 24

Dual Pumps ............................................................................................................................... 24

Pressure Gauges and Thermometers ......................................................................................... 24

Pipe Insulation ........................................................................................................................... 25

Installation..................................................................................................................................... 26

Outdoor Mechanical Room Placement...................................................................................... 26

Curb and Steel Mount Installation ............................................................................................ 26

Lifting and Handling ................................................................................................................. 27

Water Connection ...................................................................................................................... 28

Gas Connection ......................................................................................................................... 29

Boiler Exhaust Connection ........................................................................................................ 29

Boiler Intake Connection .......................................................................................................... 31

Mounting Isolation .................................................................................................................... 31

Access Doors ............................................................................................................................. 31

Low Ambient Operation ............................................................................................................ 31

LAC Valve ............................................................................................................................. 31

OROA Valve ......................................................................................................................... 32

ORI/ORD Valves ................................................................................................................... 33

Condenser Flooding ............................................................................................................... 34

Electrical .................................................................................................................................... 35

Startup ........................................................................................................................................... 38

Axial Flow Condenser Fans ...................................................................................................... 39

General ...................................................................................................................................... 42

Compressors .............................................................................................................................. 42

Refrigerant Filter Driers ............................................................................................................ 42

Evaporator/Heat Exchangers ..................................................................................................... 42

Adjusting Refrigerant Charge ................................................................................................... 42

Lubrication ................................................................................................................................ 47

Air-Cooled Condenser ............................................................................................................... 47

E-Coated Coil Cleaning ............................................................................................................ 47

Recommended Coil Cleaner .................................................................................................. 48

Recommended Chloride Remover ......................................................................................... 48

Evaporative-Cooled Condenser ................................................................................................. 48

Severe Service ....................................................................................................................... 49

Safety ..................................................................................................................................... 49

Performance ........................................................................................................................... 50

Warranties .............................................................................................................................. 50

Condenser Tube Inspection ................................................................................................... 50

Freeze Protection ................................................................................................................... 50

Recirculating Water System .................................................................................................. 50

Startup .................................................................................................................................... 50

Cleanliness ............................................................................................................................. 50

Storage ................................................................................................................................... 50

Pump Operation ..................................................................................................................... 51

Running.................................................................................................................................. 51

Condenser Fan Motors ........................................................................................................... 51

Water Make Up Valve ........................................................................................................... 51

Water Treatment System ....................................................................................................... 52

Sequence of Operation for LL Series units without Diagnostics .......................................... 53

Sequence of Operation for LL Series units with Diagnostics ................................................ 53

Pump Maintenance ................................................................................................................ 54

Fan Motor Maintenance ......................................................................................................... 54

Access Doors ......................................................................................................................... 54

Bearings - Lubrication ........................................................................................................... 54

Recommended Monthly Inspection ....................................................................................... 54

Mist Eliminators .................................................................................................................... 55

Air Inlet .................................................................................................................................. 55

Stainless Steel Base Pan ........................................................................................................ 55

Propeller Fans and Motors ..................................................................................................... 55

Recommended Annual Inspection ......................................................................................... 55

Cleaning ................................................................................................................................. 55

Water Quality ......................................................................................................................... 55

Mechanical Cleaning ............................................................................................................. 56

Service ....................................................................................................................................... 56

Replacement Parts ..................................................................................................................... 57

AAON Warranty, Service and Parts Department ...................................................................... 57

Appendix - Water Piping Component Information ...................................................................... 58

Water Pressure Reducing Valve ................................................................................................ 58

Water Pressure Relief Valve ..................................................................................................... 60

Automatic Air Vent Valves ....................................................................................................... 60

Pumps - Installation and Operating Instructions ....................................................................... 62

Pump Piping - General .............................................................................................................. 64

Pump Operation ......................................................................................................................... 64

General Care .............................................................................................................................. 65

Dual Pump Specific Information ............................................................................................... 67

Horizontal and Vertical Expansion Tanks ................................................................................ 72

Suction Guides .......................................................................................................................... 73

Glycol Auto Fill Unit ................................................................................................................ 74

Flo-Trex Combination Valve .................................................................................................... 76

LL Series Startup Form ................................................................................................................. 81

Maintenance Log .......................................................................................................................... 87

Literature Change History............................................................................................................. 88

R10100 · Rev. B · 140226

Index of Tables and Figures

Tables:

Table 1 - Service Clearances......................................................................................................... 26

Table 2 - Mounting Dimensions ................................................................................................... 27

Table 3 - Boiler Rated Input Capacity .......................................................................................... 29

Table 4 - Condenser Flooding....................................................................................................... 35

Table 5 - Return/Exhaust Fan Pin Location .................................................................................. 40

Table 6 - Return/Exhaust Fan Pin Location .................................................................................. 40

Table 7 - Fan Assembly Bushing Torque Specifications.............................................................. 41

Table 8 - Filter Drier Maximum Pressure Drop............................................................................ 42

Table 9 - Acceptable Refrigeration Circuit Values ....................................................................... 44

Table 10 - R-134a Refrigerant Temperature-Pressure Chart ........................................................ 45

Table 11 - R-410A and R-22 Refrigerant Temperature-Pressure Chart ....................................... 46

Table 12 - Recirculating Water Quality Guidelines ..................................................................... 55

Figures:

Figure 1 - Backflow Preventer ...................................................................................................... 23

Figure 2 - Pressure Relief Valve ................................................................................................... 24

Figure 3 - Curb Mounting with Dimensions ................................................................................. 26

Figure 4 - Steel Mounting Rail with Dimensions ......................................................................... 27

Figure 5 - Marked Lifting Points .................................................................................................. 27

Figure 6 - LL Series Lifting Detail ............................................................................................... 28

Figure 7 - Boiler Vent Shipping Covers ....................................................................................... 29

Figure 8 - Boiler Vent Components .............................................................................................. 30

Figure 9 - Correct Vent Pipe Connection ..................................................................................... 30

Figure 10 - Incorrect Vent Pipe Connection ................................................................................. 31

Figure 11 - Piping Schematic of Example System using the LAC Valve. ................................... 32

Figure 12 - Piping Schematic of Example System using the OROA Valve. ................................ 33

Figure 13 - Piping Schematic of Example System using the ORI/ORD Valve. ........................... 34

Figure 14 - Terminal Block ........................................................................................................... 36

Figure 15 - Evaporative-Cooled Condenser Section Layout ........................................................ 37

Figure 16 - Fan with the HUB on the top and RET on the bottom. .............................................. 39

Figure 17 - Bushing Mount Location............................................................................................ 39

Figure 18 - RET with Pin in Groove 4 .......................................................................................... 39

Figure 19 - Fan HUB and RET Castings ...................................................................................... 40

Figure 20 - Pitch Insert ................................................................................................................. 41

Figure 21 - Replaceable Core Filter Driers ................................................................................... 42

Figure 22 - Proper Unit Location .................................................................................................. 49

Figure 23 - Improper Unit Locations ............................................................................................ 50

Figure 24 - Water Makeup Valve ................................................................................................. 52

Safety

ELECTRIC SHOCK, FIRE OR

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

Improper servicing could result in dangerous operation, serious injury,

Before servicing, disconnect all electrical power to the furnace.

wires prior to disconnecting.

Verify proper operation after servicing. Secure all doors with

WARNING

Attention should be paid to the following statements:

Improper installation, adjustment, alteration, service or maintenance can cause property damage,

WARNING

Do not use any phone in the

and check all gas connections

CAUTION

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.

EXPLOSION HAZARD

property damage.

death, or property damage.



More than one disconnect may be provided.

 When servicing controls, label all

Reconnect wires correctly.



key-lock or nut and bolt.

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.

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. 

 Never test for gas leaks with an

 Use a gas detection soap solution

QUALIFIED INSTALLER

building.

open flame.

and shut off valves.

FIRE, EXPLOSION OR CARBON

Failure to replace proper controls could result in fire, explosion or carbon monoxide poisoning. Failure to follow safety warnings exactly

and liquids in the vicinity of this

Electric shock hazard. Before

to the unit, including remote disconnects, to avoid shock hazard

WARNING

Do not leave VFDs unattended in hand mode or manual bypass.

WARNING

electrical components. Only a

licensed electrician or

live electrical components shall

70E, an OSHA

regulation requiring an Arc Flash

marked for identification of where

opriate Personal Protective

followed.

WARNING

All field installed wiring must be completed by qualified personnel. Field installed wiring must comply

local and state

to follow code requirements could result in serious injury or death. Provide proper unit ground in accordance with these code

WARNING

and overload protection may be a

e Variable Frequency

CAUTION

MONOXIDE POISONING HAZARD

could result in serious injury, death or property damage. Do not store or use gasoline or other flammable vapors

appliance.

servicing, shut off all electrical power

or injury from rotating parts. Follow proper Lockout-Tagout procedures.

During installation, testing, servicing, and troubleshooting of the equipment it may be necessary to work with live

qualified individual properly trained in handling

perform these tasks.

Standard NFPA-

Boundary to be field established and

appr Equipment (PPE) be worn, should be

GROUNDING REQUIRED

with NEC/CEC, electrical code requirements. Failure

requirements.

VARIABLE FREQUENCY DRIVES

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.

Electric motor over-current protection

function of th 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.

(Chlorinated Polyvinyl Chloride) are vulnerable to attack by certain chemicals. Polyolester (POE) oils

410A and other

and fittings and complete piping system failure.

CAUTION

To prevent injury or death lifting

WARNING

Door compartments containing hazardous voltage or rotating parts

h door latches to

bolts requiring tooled

If you do not replace the

shipping hardware with a pad lock

CAUTION

Always use a pressure regulator,

ges to control

incoming pressures when pressure

WARNING

on all

should be checked for proper

CAUTION

in place of refrigerant and dry

A violent

WARNING

not use alkaline chemical coil

CAUTION

UNIT HANDLING

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.

valves and gau

testing a system. Excessive pressure may cause line ruptures, equipment damage or an explosion which may result in injury or death.

are equipped wit allow locks. Door latch are shipped with nut and access.

always re-install the nut & bolt after closing the door.

Do not use oxygen, acetylene or air

nitrogen for leak testing. explosion may result causing injury or death.

PVC (Polyvinyl Chloride) and CPVC

used with Rrefrigerants, even in trace amounts, in a PVC or CPVC piping system will result in stress cracking of the piping

Rotation must be checked 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

operation. Alterations should only be made at the unit power connection

To prevent damage to the unit, do not use acidic chemical coil cleaners. Do

cleaners with a pH value greater than

8.5, after mixing, without first using an aluminum corrosion inhibitor in the cleaning solution.

coil cleaning

Failure to follow

WARNING

water or steam on refrigerant coils will cause high pressure inside the

CAUTION

Door compartments containing hazardous voltage or rotating parts

h door latches to

bolts requiring tooled

If you do not replace the

CAUTION

used in hydrofluorocarbon (HFC) refrigeration systems. Refer to the compressor label for the proper

CAUTION

To prevent motor overheating compressors must cycle off for a

To maintain the proper oil level compressors must cycle on for a

The cycle rate must not exceed 6 starts per hour.

WARNING

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

Do not clean DX refrigerant coils with hot water or steam. The use of hot

coil tubing and damage to the coil.

COMPRESSOR CYCLING

5 MINUTE MINIMUM OFF TIME

minimum of 5 minutes.

5 MINUTE MINIMUM ON TIME

minimum of 5 minutes.

Polyolester (POE) and Polyvinylether (PVE) oils are two types of lubricants

compressor lubricant type.

are equipped wit allow locks. Door latch are shipped with nut and access. shipping hardware with a pad lock always re-install the nut & bolt after closing the door.

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. Use only with type of the gas approved

for the boiler. Refer to the boiler rating plate.

4. Provide adequate combustion ventilation

air to the boiler.

5. 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.

6. READ THE ENTIRE INSTALLATION,

OPERATION AND MAINTENANCE MANUAL. OTHER IMPORTANT SAFETY PRECAUTIONS ARE PROVIDED THROUGHOUT THIS MANUAL.

7. Keep this manual and all literature

safeguarded near or on the unit.

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 F

B–K5E–KJG–A0C0CBA–E

– 0 F

0 0B0

GEN

Model Options

Unit Feature Options

BASE MODEL

SERIES AND GENERATION

UNIT SIZE

035 = 35 ton Capacity 050 = 50 ton Capacity 055 = 55 ton Capacity 060 = 60 ton Capacity 067 = 67 ton Capacity 075 = 75 ton Capacity 085 = 85 ton Capacity 090 = 90 ton Capacity 092 = 92 ton Capacity 104 = 104 ton Capacity 105 = 105 ton Capacity 115 = 115 ton Capacity 118 = 118 ton Capacity 120 = 120 ton Capacity 125 = 125 ton Capacity 140 = 140 ton Capacity 150 = 150 ton Capacity

170 = 170 ton Capacity 180 = 180 ton Capacity 181 = 181 ton Capacity 185 = 185 ton Capacity 210 = 210 ton Capacity 230 = 230 ton Capacity 240 = 240 ton Capacity 245 = 245 ton Capacity 275 = 275 ton Capacity 300 = 300 ton Capacity 335 = 335 ton Capacity 360 = 360 ton Capacity 365 = 365 ton Capacity 450 = 450 ton Capacity 540 = 540 ton Capacity

LL Series Feature String Nomenclature

VOLTAGE

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

BLANK

0 = Standard

MODEL OPTION A: COOLING

A1: COOLING STYLE

B = R-134a Variable Capacity Oil-Free Magnetic Bearing Centrifugal Compressors D = R-410A Dual Circuited Scroll Compressors E = R-410A Independently Circuited Scroll Compressors M = R-410A VFD Compatible Scroll Compressors

A2: COOLING CONFIGURATION

0 = Air-Cooled Condenser, Low Water Flow A = Air-Cooled Condenser, High Water Flow B = Evap-Cooled Condenser, Low Water Flow C = Evap-Cooled Condenser, High Water Flow

A3: COOLING COATING

0 = Standard 1 = Polymer E-Coated Condenser Coil 2 = Stainless Steel Condenser Coil Casing

A4: COOLING STAGING

A = Shell and Tube Heat Exchanger C = Oversized Shell and Tube Heat Exchanger (Glycol) V = Shell and Tube Heat Exchanger + All Variable Speed Compressors W = Oversized Shell and Tube Heat Exchanger (Glycol) + All Variable Speed Compressors

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

CBA–E

– 0 F

0 0

GEN

Model Options

Unit Feature Options

MODEL OPTION B: HEATING

B1: HEATING TYPE

0 = No Boiler

A = Natural Gas Fired Boiler

B = Propane Fired Boiler

B2: BOILER QUANTITY

0 = No Boiler

1 = 1 Boiler

2 = 2 Boilers

3 = 3 Boilers

4 = 4 Boilers

B3: BOILER HEATING CAPACITY

0 = No Boiler

A = 500 MBH Modulating High Flow

B = 750 MBH Modulating High Flow

C = 1,000 MBH Modulating High Flow

D = 1,500 MBH Modulating High Flow

E = 500 MBH Modulating Low Flow

F = 750 MBH Modulating Low Flow

G = 1,000 MBH Modulating Low Flow

H = 1,500 MBH Modulating Low Flow

FEATURE 1: BUILDING PUMPING

1A: PUMP OPTIONS

0 = Standard - No Building Pump

A = Common Water Connections

B = Primary Pumping System

C = Primary/Secondary Pumping System

1B: PUMP CONFIGURATION

0 = Standard - No Building Pump D = 1 Pump - Prem Eff, 1170 RPM E = 2 Single Pumps - Prem Eff, 1170 RPM F = dualArm Pump - Prem Eff, 1170 RPM G = 1 Pump w/ VFD - Prem Eff, 1170 RPM H = 2 Single Pumps w/ 2 VFDs - Prem Eff, 1170 RPM J = dualArm Pump w/ 2 VFDs - Prem Eff, 1170 RPM N = 1 Pump - Prem Eff, 1760 RPM P = 2 Single Pumps - Prem Eff, 1760 RPM Q = dualArm Pump - Prem Eff, 1760 RPM R = 1 Pump w/ VFD - Prem Eff, 1760 RPM S = 2 Single Pumps w/ 2 VFDs - Prem Eff, 1760 RPM T = dualArm Pump w/ 2 VFDs - Prem Eff, 1760 RPM Y = 1 Pump - Prem Eff, 3520 RPM Z = 2 Single Pumps - Prem Eff, 3520 RPM 1 = dualArm Pump - Prem Eff, 3520 RPM 2 = 1 Pump w/ VFD - Prem Eff, 3520 RPM 3 = 2 Single Pumps w/ 2 VFDs - Prem Eff, 3520 RPM 4 = dualArm Pump w/ 2 VFDs - Prem Eff, 3520 RPM

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

1C: PUMP SIZE

0 = Standard - No Building Pump

A = Pump 4360 1.5B

B = Pump 4360 2B

C = Pump 4360 2D

D = Pump 4380 1.5x1.5x6

E = Pump 4380 2x2x6

F = Pump 4380/4382 3x3x6

G = Pump 4380/4382 4x4x6

H = Pump 4380 1.5x1.5x8

J = Pump 4380 2x2x8

K = Pump 4380/4382 3x3x8

L = Pump 4380/4382 4x4x8

M = Pump 4380 5x5x8

N = Pump 4380/4382 6x6x8

P = Pump 4380 2x2x10

Q = Pump 4380/4382 3x3x10

R = Pump 4380/4382 4x4x10

S = Pump 4380/4382 6x6x10

T = Pump 4380/4382 8x8x10

U = Pump 4380 4x4x11.5

V = Pump 4380 5x5x11.5

W = Pump 4380 6x6x11.5

Y = Pump 4380 8x8x11.5

Z = Pump 4380 4x4x13

1 = Pump 4380 6x6x13

2 = Pump 4380 8x8x13

3 = Pump 4382 6x6x6

4 = Pump 4382 8x8x8

5 = Pump 4360 3D

1D: PUMP MOTOR

0=Standard - No Building Pump A = 0.5 hp B = 0.75 hp C = 1 hp D = 1.5 hp E = 2 hp F = 3 hp G = 5 hp H = 7.5 hp J = 10 hp K = 15 hp L = 20 hp M = 25 hp N = 30 hp P = 40 hp Q = 50 hp R = 60 hp S = 75 hp

FEATURE 2: WATER CONNECTION LOCATION

0 = Back Water Connections A = Front Water Connections B = Bottom Water Connection

FEATURE 3: CHILLER ACCESSORIES

0 = Standard A = Glycol System D = Air Separator E = Options A + D F = Thermometers & Pressure Gauges + Option D G = Thermometers & Pressure Gauges + Option E

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

FEATURE 4: LOW AMBIENT

0 = Standard - None

A = One Refrigerant Circuit

B = Two Refrigerant Circuits

C = Three Refrigerant Circuits

D = Four Refrigerant Circuits

E = Five Refrigerant Circuits

F = Six Refrigerant Circuits

G = Seven Refrigerant Circuits

H = Eight Refrigerant Circuits

FEATURE 5: RECIRCULATING PUMP

5A: PUMP CONFIGURATION

0 = Standard - No Recirculating Pump

D = 1 Pump/Barrel - Prem Eff, 1170 RPM

E = 2 Single Pumps/Barrel - Prem Eff, 1170 RPM

F = dualArm Pump/Barrel - Prem Eff, 1170 RPM

G = 1 Pump/Barrel w/ VFD - Prem Eff, 1170 RPM

H = 2 Single Pumps/Barrel w/ 2 VFDs - Prem Eff,

1170 RPM

J = dualArm Pump/Barrel w/ 2 VFDs - Prem Eff,

1170 RPM

N = 1 Pump/Barrel - Prem Eff, 1760 RPM

P = 2 Single Pumps/Barrel - Prem Eff, 1760 RPM

Q = dualArm Pump/Barrel - Prem Eff, 1760 RPM

R = 1 Pump/Barrel w/ VFD, Prem Eff, 1760 RPM

S = 2 Single Pumps/Barrel w/ 2 VFDs, Prem Eff,

1760 RPM

T = dualArm Pump/Barrel w/ 2 VFDs, Prem Eff,

1760 RPM

Y = 1 Pump/Barrel -Prem Eff, 3520 RPM

Z = 2 Single Pumps/Barrel - Prem Eff, 3520 RPM

1 = dualArm Pump/Barrel - Prem Eff, 3520 RPM

2 = 1 Pump/Barrel w/ VFD - Prem Eff, 3520 RPM

3 = 2 Single Pumps/Barrel w/ 2 VFDs - Prem Eff,

3520 RPM

4 = dualArm Pump/Barrel w/ 2 VFDs - 3520 RPM

5B: PUMP SIZE

0 = Standard - No Recirculating Pump

A = Pump 4360 1.5B

B = Pump 4360 2B

C = Pump 4360 2D

D = Pump 4380 1.5x1.5x6

E = Pump 4380 2x2x6

F = Pump 4380/4382 3x3x6

G = Pump 4380/4382 4x4x6

H = Pump 4380 1.5x1.5x8 J = Pump 4380 2x2x8 K = Pump 4380/4382 3x3x8 L = Pump 4380/4382 4x4x8 M = Pump 4380 5x5x8 N = Pump 4380/4382 6x6x8 P = Pump 4380 2x2x10 Q = Pump 4380/4382 3x3x10 R = Pump 4380/4382 4x4x10 S = Pump 4380/4382 6x6x10 T = Pump 4380/4382 8x8x10 U = Pump 4380 4x4x11.5 V = Pump 4380 5x5x11.5 W = Pump 4380 6x6x11.5 Y = Pump 4380 8x8x11.5 Z = Pump 4380 4x4x13 1 = Pump 4380 6x6x13 2 = Pump 4380 8x8x13 3 = Pump 4382 6x6x6 4 = Pump 4382 8x8x8 5 = Pump 4360 3D

5C: PUMP MOTOR

0=Standard - No Recirculating Pump A = 0.50 hp B = 0.75 hp C = 1 hp D = 1.5 hp E = 2 hp F = 3 hp G = 5 hp H = 7.5 hp J = 10 hp K = 15 hp L = 20 hp M = 25 hp N = 30 hp P = 40 hp Q = 50 hp R = 60 hp S = 75 hp

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

FEATURE 6: BOILER BUILDING

PUMP

6A: PUMP CONFIGURATION

0 = Standard - No Boiler

D = 1 Pump - Prem Eff, 1170 RPM

E = 2 Single Pumps - Prem Eff, 1170 RPM

F = dualArm Pump - Prem Eff, 1170 RPM

G = 1 Pump w/ VFD - Prem Eff, 1170 RPM

H = 2 Single Pumps w/ 2 VFDs - Prem Eff, 1170

RPM

J = dualArm Pump w/ 2 VFDs - Prem Eff, 1170 RPM

N = 1 Pump - Prem Eff, 1760 RPM

P = 2 Single Pumps - Prem Eff, 1760 RPM

Q = dualArm Pump - Prem Eff, 1760 RPM

R = 1 Pump w/ VFD - Prem Eff, 1760 RPM

S = 2 Single Pumps w/ 2 VFDs - Prem Eff, 1760

RPM

T = dualArm Pump w/ 2 VFDs - Prem Eff, 1760

RPM

Y = 1 Pump - Prem Eff - 3520 RPM

Z = 2 Single Pumps - Prem Eff, 3520 RPM

1 = dualArm Pump - Prem Eff, 3520 RPM

2 = 1 Pump w/ VFD - Prem Eff, 3520 RPM

3 = 2 Single Pumps w/ 2 VFDs - Prem Eff, 3520

RPM

4 = dualArm Pump w/ 2 VFDs - Prem Eff, 3520

RPM

6B: PUMP SIZE

0 = Standard - No Boiler

A = Pump 4360 1.5B

B = Pump 4360 2B

C = Pump 4360 2D

D = Pump 4380 1.5x1.5x6

E = Pump 4380 2x2x6

F = Pump 4380/4382 3x3x6

G = Pump 4380/4382 4x4x6

H = Pump 4380 1.5x1.5x8

J = Pump 4380 2x2x8

K = Pump 4380/4382 3x3x8

L = Pump 4380/4382 4x4x8

M = Pump 4380 5x5x8

N = Pump 4380/4382 6x6x8

P = Pump 4380 2x2x10

Q = Pump 4380/4382 3x3x10

R = Pump 4380/4382 4x4x10

S = Pump 4380/4382 6x6x10

T = Pump 4380/4382 8x8x10 U = Pump 4380 4x4x11.5 V = Pump 4380 5x5x11.5 W = Pump 4380 6x6x11.5 Y = Pump 4380 8x8x11.5 Z = Pump 4380 4x4x13 1 = Pump 4380 6x6x13 2 = Pump 4380 8x8x13 3 = Pump 4382 6x6x6 4 = Pump 4382 8x8x8 5 = Pump 4360 3D

6C: PUMP MOTOR

0 = Standard - No Boiler A = 0.50 hp B = 0.75 hp C = 1 hp D = 1.5 hp E = 2 hp F = 3 hp G = 5 hp H = 7.5 hp J = 10 hp K = 15 hp L = 20 hp M = 25 hp N = 30 hp P = 40 hp Q = 50 hp R = 60 hp S = 75 hp

FEATURE 7: SERVICE OPTIONS

0 = Standard A = 115V Outlet, Factory Wired B = 115V Outlet, Field Wired

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

FEATURE 8: REFRIGERATION

OPTIONS

0 = Standard

B = VFD Controlled Condenser Fans (Air-Cooled)

D = Hot Gas Bypass - All Circuits

E = Options B + D

FEATURE 9: REFRIGERATION

ACCESSORIES

0 = Standard

A = Sight Glass

B = Compressor Isolation Valves

C = Options A + B

FEATURE 10: POWER OPTIONS

0 = Standard Power Block

A = Power Switch (225 Amps)

B = Power Switch (400 Amps)

C = Power Switch (600 Amps)

D = Power Switch (800 Amps)

E = Power Switch (1200 Amps)

F = Dual Point Power Block (2)

G = Dual Point Power Switch (2 x 225 Amps)

H = Dual Point Power Switch (2 x 400 Amps)

J = Dual Point Power Switch (2 x 600 Amps)

K = Dual Point Power Switch (2 x 800 Amps)

L = Dual Point Power Switch (2 x 1200 Amps)

FEATURE 11: SAFETY OPTIONS

0 = No Boiler

A = Standard, Boiler w/ UL/FM/CSD-1 Certification

B = Boiler w/ IRI Gas Train

C = Boiler w/ IRI Gas Train and Proof of Closure

D = Boiler w/ Low Water Cutoff

E = Options B + D

F = Options C + D

FEATURE 12: CONTROLS

0 = Standard A = Touchscreen Unit Controls Interface B = Phase and Brown Out Protection F = Options A + B

FEATURE 13: SPECIAL CONTROLS

0 = MCS Magnum Controller A = w/ Diagnostics C = w/ Diagnostics and Modbus Connection D = w/ Diagnostics and N2 Connection E = w/ Diagnostics and LonTalk Connection G = w/ Modem H = w/ Diagnostics and Modem K = w/ Diagnostics, Modbus Connection and Modem L = w/ Diagnostics, N2 Connection and Modem M = w/ Diagnostics, LonTalk Connection and Modem Q = w/ Modbus Connection R = w/ N2 Connection S = w/ LonTalk Connection V = w/ Modbus Connection and Modem W = w/ N2 Connection and Modem Y = w/ LonTalk Connection and Modem 1 = w/ BACnet IP Connection 2 = w/ Diagnostics and BACnet IP Connections 3 = w/ Diagnostics, BACnet IP Connection and Modem 4 = w/ BACnet IP Connection and Modem 5 = w/ BACnet MS/TP Connection 6 = w/ Diagnostics and BACnet MS/TP Connection 7 = w/ Diagnostics, BACnet MS/TP Connection and Modem 8 = w/ BACnet MS/TP Connection and Modem

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

FEATURE 14: COMPRESSION TANK

14A: CHILLER COMPRESSION TANK

0 = No Chiller Compression Tank

A = AX-15V

B = AX-20V

C = AX-40V

D = AX-60V

E = AX-80V

F = AX-100V

G = AX-120V

H = AX-180V

J = AX-200V

K = AX-240V

L = AX-260V

M = AX-280V

N = 1000-L

P = 1200-L

Q = 1600-L

R = 2000-L

14B: BOILER COMPRESSION TANK

0 = No Boiler Compression Tank

A = AX-15V

B = AX-20V

C = AX-40V

D = AX-60V

E = AX-80V

F = AX-100V

G = AX-120V

H = AX-180V

J = AX-200V

K = AX-240V

L = AX-260V

M = AX-280V

N = 1000-L

P = 1200-L

Q = 1600-L

R = 2000-L

FEATURE 15: OPTION BOXES

0 = Standard A = 2ft Option Box B = 4ft Option Box C = 6ft Option Box D = 8ft Option Box E = 10ft Option Box F = 12ft Option Box

FEATURE 16: CABINET OPTIONS

0 = Standard A = Electrical Vestibule Heating B = Fan/Coil Vestibule Cooling F = Options A + B

FEATURE 17: CABINET OPTIONS

0 = Standard A = Access Door Windows

FEATURE 18: CUSTOMER CODE

0 = Standard A = Second to Fifth Year Extended Compressor Warranty

LL Series Feature String Nomenclature

SIZE

VLT

CONFIGA1A2A3A4B1B2B31A1B1C1D2345A5B5C6A6B6C7891011121314A

14B1516171819202122

– 0 7 5 – 3 – 0 –

B0A–A2C:C

RJG

– 0 FB–K5E–KJG–A0C0

A–E

– 0 F

0 0B0

Model Options

Unit Feature Options

GEN

FEATURE 19: CODE OPTIONS

0 = Standard - ETL U.S.A. Listing

A = M.E.A. (New York)

B = Chicago - Cool + Gas

H = ETL U.S.A. + Canada Listing

FEATURE 20: UNIT

CONFIGURATION

0 = Standard (One Piece Unit)

A = Two Piece Unit

FEATURE 21: EVAPORATIVE-

COOLED CONDENSER

0 = Standard - No Evaporative-Cooled Condenser

A = No Sump Heater

B = Sump Heater

FEATURE 22: BLANK

0 = Standard

FEATURE 23: TYPE

B = Standard Paint

U = Special Price Authorization and Special Paint

X = Special Price Authorization and Standard Paint

General Information

Improper installation, adjustment, alteration, service or maintenance can cause property damage,

WARNING

July 1, 1992. Approved methods of recovery, recycling, or reclaiming

CAUTION

metal surfaces

be taken when working with

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

WARNING

AAON LL Series chiller outdoor

mechanical rooms are complete self-

contained liquid chilling units. They are

assembled, wired, charged, and run-tested.

Models are available for air-cooled and

evaporative-cooled applications. Chiller

primary and primary/secondary pumping

packages and boilers with pumping package

are available as optional features.

personal injury or loss of life. Startup and service must be performed by a Factory Trained Service Technician.

Codes and Ordinances

LL 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 LL 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.

The Clean Air Act of 1990 bans the intentional venting of refrigerant as of

must be followed.

Coils and sheet present sharp edges and care must

equipment.

voiding of the warranty.

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.

Outdoor Mechanical Room

Scroll compressors are directional

the wrong direction. Low pressure

disconnected after factory testing. Rotation should be checked by a

gauges and any wiring alteration should only be made at the unit

Rotation must be checked on all

three phase units. All motors, to include and not be limited to pump

Units may be equipped with compressor crankcase heaters,

clear any liquid refrigerant from the

CAUTION

motor overheating

compressors must cycle off for a

To maintain the proper oil level compressors must cycle on for a

The cycle rate must not exceed 6 starts per hour.

WARNING

COMPRESSOR CYCLING

5 MINUTE MINIMUM OFF TIME

To prevent

minimum of 5 minutes.

5 MINUTE MINIMUM ON TIME

minimum of 5 minutes.

Failure to observe the following instructions

will result in premature failure of your

system, and possible voiding of the

warranty.

CRANKCASE HEATER

OPERATION

which should be energized at least 24 hours prior to cooling operation, to

compressors.

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.

MOTORS AND COMPRESSORS of

motors and condenser fan motors, should all be checked by a qualified service technician at startup and any wiring alteration should only be made at the unit power connection.

Before 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.

and will be damaged by operation in

switches on compressors have been

qualified service technician at startup using suction and discharge pressure

power connection.

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

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 and boiler.

This includes reading and recording suction

pressures and checking for normal sub-

cooling and superheat. See the evaporative-

cooled condenser and 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 evaporator barrel 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 chiller barrel leaves the unit through the water out connection.

Chiller Primary/Secondary Pumping

Primary/secondary pumping option provides variable flow to the system. It consists of a constant flow pump for the chiller heat exchanger and a variable flow pump for the building. The controls package senses differential pressure across the pump with pressure transducers installed at the suction and discharge, and varies the speed of the pump using a VFD in order to maintain a given differential pressure across the pump.

The primary/secondary pumping package is essentially composed of two piping loops

coupled together. The primary loop has a

constant flow rate in order to keep the chiller

heat exchanger from freezing, and the

secondary, variable flow loop, provides

water to the building. The two loops are

coupled via a water line that compensates

for excess flow in either loop. As the flow in

the secondary loop decreases below the flow

in the primary loop, excess flow bypasses

the building loop and circulates through the

bypass water line. On the other hand, as the

flow in the secondary loop increases above

the flow in the primary loop, excess flow

bypasses the chiller and circulates through

the bypass water line.

The secondary pump has its own suction

guide, combination valve, and isolation

valve, similar to the primary pump, with the

addition of an air separator to remove any

air that is entrapped in the water.

Boiler System

Optional boilers and pumping packages are

factory installed. The boiler system uses a

primary/secondary pumping package. There

can be 1-4 boilers in parallel and each boiler

has its own primary pump. The heating loop

must be designed to return at least 120°F

water to the boiler during normal operation.

Failure to return 120°F water to the boiler

will create condensation, which will reduce

the life of the heat exchanger and void the

boiler warranty. See unit submittal for unit

specific piping schematics. See the Thermal

Solutions Boiler “Installation, Operating,

and Service Instructions” that are included

with the unit for additional information

about the boiler.

Once the boiler is given a run signal, the

boiler secondary pump will be activated and

the controls package will stage boilers as

necessary to maintain the leaving water

temperature setpoint.

The controls package will also control the speed of the secondary pump in the boiler system to maintain differential pressure across the pump similar to the chiller secondary pump.

Boiler Primary/Secondary Pumping

Water enters the unit through the return water piping, and then travels 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 primary/secondary pumping package provides variable flow to the system. It consists of a constant flow pump for the boiler, and a variable flow pump for the building. The controls package senses differential pressure across the pump with pressure transducers installed at the suction and discharge, and varies the speed of the pump using a VFD in order to maintain a given differential pressure across the pump.

The primary/secondary pumping package is essentially composed of two piping loops coupled together. The primary loop has a constant flow rate in order to maintain water temperature through the boiler, and the secondary, variable flow loop, provides water to the building. The two loops are coupled via a water line that compensates for excess flow in either loop. As the flow in the secondary loop decreases below the flow in the primary loop, excess flow bypasses

the building loop and circulates through the

bypass water line. On the other hand, as the

flow in the secondary loop increases above

the flow in the primary loop, excess flow

bypasses the boiler and circulates through

the bypass water line.

The secondary pump includes suction guide,

combination valve, and isolation valve with

the addition of an air separator to remove

any air that is entrapped in the water.

See appendix for additional information on

the installation, operation and maintenance

of pumps.

Make Up Water

A city make up water connection is provided

to replace water that is lost from the system.

Glycol units require a glycol feeder

(optional factory installed or field installed)

to replace fluid that is lost in the system.

Water should not be directly added to glycol

applications as this would dilute the glycol

concentration and thereby increase the

freezing temperature of the fluid.

The makeup water connection is provided

with a backflow preventer that has isolation

valves on the inlet and outlet for service.

Figure 1 shows the pressure drop versus

flow rate for the backflow preventer.

Figure 1 - Backflow Preventer

There is a pressure-reducing valve after the

backflow preventer. This valve reduces the

city water pressure to maintain the operating pressure of the system. This valve is adjustable from 10-35 psig with a factory setting of 30 psig. The system pressure varies with the height of the system. The pressure-reducing valve setting should be set so that the pressure at the high point in the system is high enough to vent air from the system (usually 4 psig). There should be air vents at all parts in the system where air could be trapped. If the pressure is not high enough throughout the system, flashing could occur in the piping or the pump could cavitate. There is an isolation valve on the inlet and outlet of the pressure-reducing valve for service.

The pressure reducing valve fills the system at a reduced rate. There is a bypass around the pressure reducing valve for the initial fill of the system to increase the initial fill speed. After the initial system fill, this valve should be closed.

Compression/Expansion Tank

As the water temperature in the system increases, the volume that water displaces increases. In order to compensate for these expansion forces, a compression or expansion tank must be used. The factory installed tank option includes a prepressurized diaphragm compression tank that is preset for 12 psig.

The factory pre-charge pressure may need to be field adjusted. The tank must be precharged to system design fill pressure before placing into operation. Remove the pipe plug covering the valve enclosure. Check and adjust the charge pressure by adding or releasing air.

If the system has been filled, the tank must be isolated from the system and the tank emptied before charging. This ensures that

all fluid has exited the diaphragm area and

proper charging will occur.

If the pre-charge adjustment is necessary, oil

and water free compressed air or nitrogen

gas may be used. Check the pre-charge

using an accurate pressure gauge at the

charging valve and adjust as required. Check

air valve for leakage. If evident, replace the

Schrader valve core. Do not depend on the

valve cap to seal the leak. After making sure

the air charge is correct, replace the pipe

plug over the charging valve for protection.

Purge air from system before placing tank

into operation. All models have system

water contained behind the diaphragm.

It is recommended that the pre-charge be

checked annually to ensure proper system

protection and long life for the vessel.

Pressure Relief Valve

Required pressure relief valve is installed in

the unit. This valve is set at 125 psig. Figure

2 shows inlet pressure versus capacity for

this pressure relief valve. See appendix for

additional information.

Figure 2 - Pressure Relief Valve

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 or two single 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 split-flapper valve in the discharge port to prevent liquid recirculation when only one pump is operating. Isolation valves in the casing allow one pump to be isolated and removed for service while the other pump is still operating.

When redundant pumping is required with high flow rates, two independent pumps may be installed in parallel. Each pump will have its own suction guide/strainer, combination valve, and isolation valves.

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

Unit Size

35-540 tons

Front -

(Controls Side)

Back

100”

Ends

100”

Top

Unobstructed

CAUTION

Outdoor Mechanical Room Placement

The AAON LL 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

Location

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

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

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

100”

from damage due to vandalism or other causes.

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

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.

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.

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,

and gas penetrations and workspace only.

Do not make openings larger than necessary.

Set the curb to coincide with the openings.

Make sure curb is level.

Figure 3 - Curb Mounting with Dimensions

Tons

A B C

35-115

(Scroll)

125-365

(Scroll)

90-540

(Centrifugal)

Figure 4 - Steel Mounting Rail with

Dimensions

Table 2 - Mounting Dimensions

100” 96” 92” 97”

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 5 - Marked Lifting Points

142” 138” 134” 139”

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 6 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

Lifting slot locations are unit specific.

(Chlorinated Polyvinyl Chloride) are

attack by certain

chemicals. Polyolester (POE) oils

410A and other

and fittings and complete piping system failure.

CAUTION

The chiller must be operated only with liquid flowing through the

WARNING

Unit must be rigged at all marked lifting points.

Water Connection

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 LL Series

units is 125 psi.

evaporators.

Figure 6 - LL Series Lifting Detail

PVC (Polyvinyl Chloride) and CPVC

vulnerable to

used with Rrefrigerants, even in trace amounts, in a PVC or CPVC piping system will result in stress cracking of the piping

Rated Capacity (CFH)*

Natural

LP/Propane

500 MBH

500

200

750 MBH

750

300

1000 MBH

1000

400

1500 MBH

1500

600

Boilers must be operated only with

WARNING

Installing Contractor is responsible

unit and property.

CAUTION

liquid flowing through the boiler.

for proper sealing of the water piping entries into the unit Failure to seal the entries may result in damage to the

Gas Connection

For LL Series outdoor mechanical units with

boiler systems, size gas piping to supply the

unit with proper pressure when all gas

consuming devices in the building

connected to the same gas system are

operating. The maximum gas train inlet

pressure for all boiler sizes is 5 psig. The

minimum gas train inlet pressure for the 500

MBH boiler is 5 inches of water column,

and for all other boilers, 7 inches of water

column.

Carefully consider all current and future gas

usage. Table 3 details the input rate for each

boiler unit.

Gas connection sizes are listed on the unit

rating sheet.

Table 3 - Boiler Rated Input Capacity

Solutions Boiler “Installation, Operating, and Service Instructions” that are included with the unit.

Boiler Exhaust Connection

In addition to gas connection installation, each boiler requires installation of the exhaust vent piping and inlet vent hood. The exhaust panel with chimney cutout is removed for shipping, and replaced with a shipping cover.

Boiler Size

*Note: Rating is for sea level conditions.

For additional information regarding the gas

piping connection, see the Thermal

Figure 7 - Boiler Vent Shipping Covers

Remove the shipping cover and attach the exhaust panel shipped with the unit. When the exhaust panel is securely fastened with

sheet metal screws, locate the exhaust piping

Failure to follow proper joint connection procedure may result in

WARNING

that is also shipped along with the unit. The

exhaust piping that must be attached to the

internal exhaust vent piping includes the

vent length, 90 degree elbow and rain cap.

Examine all components prior to

installation. The female end of each vent

pipe component incorporates a sealing

gasket and a mechanical locking band.

Intake and exhaust covers are in place for shipping. These must be removed and external intake/exhaust components must be installed prior to boiler operation.

Gasket must be in proper position or flue gases could leak.

carbon monoxide gas poisoning due to flue gas leakage.

Securely fasten the vent pipe joints according to the following procedure.

1. Insert the male end into the female

section. Push the units together and turn them until the bead of the male end is seated against the flared end of the female section. This creates the necessary airtight seal. Align the seams on the vent lengths and orient them upward in all horizontal applications.

2. Tighten the locking band with a nut

driver until snug plus 1/4 turn.

Before proceeding, recheck all joints and ensure that all male sections extend to the top of the flared female end and all clamps are tightened.

Figure 8 - Boiler Vent Components

Figure 9 - Correct Vent Pipe Connection

Figure 10 - Incorrect Vent Pipe Connection

Stop bead on male end must be pushed

directly against the flared end of the female

end. When checking the inside of the joint,

the gasket is fully covered and out of sight.

Boiler Intake Connection

Remove the intake shipping cover. The

round collar on the back of the intake vent

passes through the cabinet wall and slides

over the crimped end of the air intake pipe

inside the unit. This joint should be secured

with aluminum foil tape. The outer flange of

the wall vent is fastened to the outer wall of

the cabinet using sheet metal screws.

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

evaporator and pumping package

compartment.

A light switch is provided on the wall of the

compressor and control compartment.

Low Ambient Operation

If the chiller is ordered with the Low Ambient feature, 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.

The AAON low ambient (condenser floodback) system is used to operate a refrigerant system below 25°F outside air temperature. As the ambient temperature drops, the condenser becomes more effective therefore lowering the head pressure. When the head pressure gets too low, there will be insufficient pressure to operate the expansion valve properly. During low ambient temperatures, it is difficult to start a system because the refrigerant will migrate to the cold part of the system (condenser) and make it difficult for refrigerant to flow.

The low ambient system maintains normal head pressure during periods of low ambient by restricting liquid flow from the condenser to the receiver, and at the same time bypassing hot gas around the condenser to the inlet of the receiver. This backs liquid refrigerant up into the condenser reducing its capacity that in turn increases the condensing pressure. At the same time the bypassed hot gas raises liquid pressure in the receiver, allowing the system to operate properly. There are different types of low ambient control used. The following describe the different systems. Inspect the unit to determine the system used.

LAC Valve

The LAC valve is a non-adjustable three way valve that modulates to maintain receiver pressure. As the receiver pressure drops below the valve setting (180 psig for R-22 and 295 psig for R-410A), the valve

modulates to bypass discharge gas around

the condenser. The discharge gas warms the

liquid in the receiver and raises the pressure

to the valve setting. The following

schematic shows an example system using the LAC valve.

Figure 11 - Piping Schematic of Example System using the LAC Valve.

OROA Valve

This system uses a non-adjustable head

pressure control valve that performs the

function of limiting the flow of liquid

refrigerant from the condenser and at the

same time regulates the flow of the hot gas

around the condenser to the receiver. The

valve setpoint is 180 psig. This valve is

called an OROA valve (Open on Rise of

Outlet pressure). The following schematic

shows an example system using the OROA

valve.

Figure 12 - Piping Schematic of Example System using the OROA Valve.

ORI/ORD Valves

This system uses a two valve arrangement.

The head pressure control valve is an inlet

pressure regulating valve and responds to

changes in condensing pressure. This valve

is located in the discharge of the condenser

and is called an ORI valve (Open on Rise of

Inlet pressure). As the ambient temperature

drops, the condenser capacity increases and

the condensing pressure falls, causing the

ORI to modulate toward the closed position.

The condenser bypass valve is a pressure

differential valve that responds to changes in

the pressure differential across the valve.

This valve is called an ORD valve (Open on

Rise of Differential pressure). As the ORI

starts to restrict liquid flow from the

condenser, a pressure differential is created across the ORD. When the differential reaches the setpoint, the ORD starts to open and bypass hot gas to the liquid line. The ORI valve is adjustable from 65 to 225 psig (factory setting of 180 psig). The ORD is not adjustable. On refrigeration systems that are too large for a single ORI and ORD valve, there will be two ORI and two ORD valves in parallel. The following schematic shows an example system using the ORI/ORD valves.

Figure 13 - Piping Schematic of Example System using the ORI/ORD Valve.

The pressure setting of the ORI valve

determines how well the system will

operate. The proper setting is a function of

the specific system in which is installed.

Generally, the setting should be equivalent

to a condensing temperature of 90°F to

100°F or a receiver pressure equivalent to a

temperature of 80°F to 90°F. This means

that as the ambient temperature falls below

70°F, the head pressure control valve will

begin to throttle. To adjust the ORI valve,

remove the cap and turn the adjustment

screw with the proper size hex wrench (1/4”

for ORI-6 and 5/16” for ORI-10). A

clockwise rotation increases the valve

setting while a counter-clockwise rotation

decreases the setting. To obtain the desired

setting, a pressure gauge should be used at

the compressor discharge service valve so

the effects of any adjustment can be

observed. Small adjustments are

recommended in order to allow the system

adequate time to stabilize after each adjustment.

Condenser Flooding

In order to maintain head pressure in the refrigeration system, liquid refrigerant is backed up in the condenser to reduce condenser surface. The following chart shows the percentage that a condenser must be flooded in order to function properly at the given ambient temperature.

Table 4 - Condenser Flooding

PERCENTAGE OF CONDENSER TO BE

Electric shock hazard. Before

electrical power to the unit at the

multiple power supplies. Failure to disconnect power could result in

WARNING

Installing Contractor is responsible

lt in

CAUTION

FLOODED

Ambient

Temperature

°F)

(

70°

60°

50°

40°

30°

20°

0°

-20°

Evaporating Temperature (

0° 10° 20° 30° 35° 40° 45° 50°

40 24 0 0 0 0 0 0

60 47 33 17 26 20 10 4

70 60 50 38 45 40 33 28

76 68 60 50 56 52 46 42

80 73 66 59 64 60 55 51

86 77 72 65 69 66 62 59

87 83 78 73 76 73 70 68

91 87 82 77 80 79 76 73

During higher ambient temperatures the

entire condenser is required to condense

refrigerant. During these higher ambient

temperatures, a receiver tank is used to

contain the refrigerant that was required to

flood the condenser during low ambient

operation. The receiver must be sized to

contain all of the flooded volume otherwise

there will be high head pressures during

higher ambient conditions.

Electrical

The single point electrical power

connections are made in the electrical

control compartment.

The microprocessor control furnished with

the unit is supplied with its own power

supply factory wired to the main power of

the 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).

°F)

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.

attempting to perform any installation, service, or maintenance, shut off all

disconnect switches. Unit may have

dangerous operation, serious injury, death or property damage.

for proper sealing of the electrical and gas entries into the unit Failure to seal the entries may resu damage to the unit and property.

Figure 14 - Terminal Block

Rotation must be checked on all

three phase units. Condenser fan

be made at the unit power

are programmed to automatically rotate the fan in the correct rotation.

ith variable

frequency drives for compressor

CAUTION

Scroll compressors are directional

the wrong direction. Low pressure

factory testing.

Rotation should be checked by a

gauges and any wiring alteration should only be made at the unit

CAUTION

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

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.

Evaporative-Cooled Condenser Field Piping

Connections

MOTORS AND COMPRESSORS of

motors should all be checked by a qualified service technician at startup and any wiring alteration should only

connection. Variable frequency drives

Do not rely on fans w

rotation.

and will be damaged by operation in

switches on compressors have been disconnected after

qualified service technician at startup using suction and discharge pressure

power connection.

There are at least two field water connections that must be made for the evaporative-cooled condenser. There is a 3/4” PVC socket city make up water connection and a 2” PVC socket drain connection, as shown in Figure 15. This drain should connect to a sanitary sewer or other code permitted drain. These connections can go through the base or the wall of the unit. There is a cutout in the base with a cap that is 1” tall and the cap is sealed to the unit base to prevent any leaks in the unit from

penetrating into the building. Any piping

through the base should go through a field

cutout in this cap. The pipes must be sealed

to the cap once the piping is complete to

prevent any leaks in the unit from

penetrating into the building.

A field cutout must be made in the wall if the evaporative-cooled condenser piping is to go through the unit wall. This cutout must be sealed once the piping is installed to prevent water from leaking into the unit.

Figure 15 - Evaporative-Cooled Condenser Section Layout

Including Field Water Connections and Base Cutout

Startup

Electric shock hazard. Shut off all

WARNING

Improper installation, adjustment, alteration, service or maintenance can cause property damage,

WARNING

Rotation must be checked on all

three phase units. All motors, to

motors and condenser fan motors,

CAUTION

(See back of the manual for startup form)

electrical power to the unit to avoid shock hazard or injury from rotating parts.

personal injury or loss of life. Startup and service must be performed by a Factory Trained Service Technician.

Before the startup of the chiller and boilers

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 (and boiler) controller is requesting the chiller (and boiler) to start.

3. Verify that liquid flow is present through

the chiller (and boiler) from the building.

4. There should be a building load of at

least 25% of the chiller (and boiler) 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.

MOTORS AND COMPRESSORS of

include and not be limited to pump

should all be checked by a qualified service technician at startup and any wiring alteration should only be made at the unit power connection.

Cycle through all the compressors (and boilers) to confirm that all are operating within tolerance.

While performing the check, use the startup form to record observations of compressor amps, refrigerant pressures and boiler amps.

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.

Before completing installation, a

observed to verify that all

CAUTION

Bushing Mount

Bushing Bushing

Bushing

complete operating cycle should be

components are functioning properly.

Axial Flow Condenser Fans

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.

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.

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.

Mount

Figure 17 - 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 16 - 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.

Figure 18 - RET with Pin in Groove 4

5. Determine whether the pin is in the HUB

Bushing

Mount

Blade Pitch Angle

20°

25°

28°

30°

33°

35°

38°

40°

45°

50°

RET

HUB

HUB B -

HUB

RET

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 19 - Fan HUB and RET Castings

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

Table 5 - Return/Exhaust Fan Pin Location

Type

Type Rot.

Table 6 - Return/Exhaust Fan Pin Location

7. Replace fan blades in the new pin

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

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

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 20 - 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 7 - Fan Assembly Bushing Torque

Specifications

Bushing

Maintenance

Circuit Loading

Max. Pressure Drop

100%

10 psig

50%

5 psig

WARNING

MUST BE attached to in

and out pressure connections to

compliance could

result in injury or violation of EPA

WARNING

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 and evaporative-cooled

condenser units require different

maintenance schedules/procedures. Unit

specific instructions for both types are

included in this manual.

Compressors

The scroll compressors are fully hermetic

and require no maintenance except keeping

the shell clean.

Refrigerant Filter Driers

Each refrigerant circuit contains a

replaceable core filter drier. Replacement is

recommended when there is excessive

pressure drop across the assembly or

moisture is indicated in a liquid line sight

glass.

Table 8 - Filter Drier Maximum Pressure

Drop

The filter driers are provided with pressure taps and shutoff valves for isolation when changing the core. For safety purposes a service manifold must be attached prior to filter maintenance.

Service gauges MUST BE connected before operating the isolation valves for the liquid line filter drier.

Prior to filter core service, a service manifold

assure no pressure exist during filter maintenance. No-

regulations.

Figure 21 - Replaceable Core Filter Driers

Evaporator/Heat Exchangers

Evaporators are direct expansion type with an electronic expansion valve or thermal expansion valve to regulate refrigerant. Normally no maintenance or service work will be required.

Adjusting Refrigerant Charge

All AAON chillers are shipped with a full factory charge. Periodically 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 sub-

intentional venting of refrigerant

recycling or reclaiming must be

Fines and/or incarceration

CAUTION

used in hydrofluorocarbon (HFC) refrigeration systems. Refer to the

for the proper

CAUTION

cooling is more representative of the charge

than evaporator superheat but both

measurements must be taken.

Polyolester (POE) and Polyvinylether (PVE) oils are two types of lubricants

compressor label compressor lubricant type.

The Clean Air Act of 1990 bans the

(CFC’s and HCFC’s) as of July 1,

1992. Approved methods of recovery,

followed. may be levied for non-compliance.

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 9 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 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

Air-Cooled Condenser with Scroll Compressors

Sub-Cooling

12-18°F

Superheat

10-15°F

Evaporative-Cooled Condenser with Scroll Compressors

Sub-Cooling

6-10°F

Superheat

10-15°F

Expansion valves must be adjusted

superheat will damage the

CAUTION

Refrigerant overcharging leads to excess refrigerant in the condenser

CAUTION

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 9 for

the appropriate unit type and options.

Table 9 - Acceptable Refrigeration Circuit

Values

temperature range as shown in Table 9 (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.

DO NOT OVERCHARGE!

coils resulting in elevated compressor discharge pressure.

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

One compressor running in tandem

Two compressors running in tandem

to approximately 10-15°F of suction superheat. Failure to have sufficient

compressor and void the warranty.

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

superheat.

Special Low Ambient Option Charging Instructions

For units equipped with low ambient refrigerant flood back option being charged in the summer when the ambient temperature is warm:

Once enough charge has been added to get the evaporator superheat and sub-cooling values to the correct setting more charge must be added. Add approximately 80% of the receiver tank volume to the charge to help fill the receiver tank. The additional charge is required for the system when running in cold ambient conditions.

For units equipped with low ambient refrigerant flood back option being charged

in the summer when the ambient

°F

PSIG

°F

PSIG

°F

PSIG

111

149

113

154

115

158

117

163

118

167

120

172

122

177

124

181

126

186

127

191

129

197

131

202

133

207

135

213

100

136

218

104

138

224

107

140

229

111

142

235

114

144

241

118

145

247

121

147

253

100

125

149

260

102

129

151

266

104

133

153

272

106

137

154

279

108

141

156

286

109

145

158

293

Refrigerant overcharging leads to excess refrigerant in the condenser

CAUTION

temperature is cold:

Once enough charge has been added to get

the evaporator superheat and sub-cooling

values to the correct setting more charge

may need to be added. If the ambient

temperature is 0°F no more charge is

required. If the ambient temperature is

around 40°F add approximately 40% of the

receiver tank volume.

Table 10 - R-134a Refrigerant Temperature-Pressure Chart

The unit will have to be checked for proper operation once the ambient temperature is above 80°F.

DO NOT OVERCHARGE!

coils resulting in elevated compressor discharge pressure.

Table 11 - R-410A and R-22 Refrigerant Temperature-Pressure Chart

PSIG

R-410A R-22 R-410A R-22 R-410A R-22 R-410A R-22 R-410A R-22

78.3 43.1

PSIG

142.2 84.1

234.9 143.6

PSIG

110

PSIG

364.1 226.4

140

540.1 337.4

PSIG

80.0 44.2

81.8 45.3

83.6 46.5

85.4 47.6

87.2 48.8

89.1 50.0

91.0 51.2

92.9 52.4

94.9 53.7

96.8 55.0

98.8 56.2

100.9 57.5

102.9 58.8

105.0 60.2

107.1 61.5

109.2 62.9

111.4 64.3

144.8 85.7

147.4 87.4

150.1 89.1

152.8 90.8

155.5 92.6

158.2 94.4

161.0 96.1

163.8 98.0

166.7 99.8

169.6 101.6

172.5 103.5

175.4 105.4

178.4 107.3

181.5 109.3

184.5 111.2

187.6 113.2

190.7 115.3

238.6 146.0

242.3 148.4

246.0 150.8

249.8 153.2

253.7 155.7

257.5 158.2

261.4 160.7

265.4 163.2

269.4 165.8

273.5 168.4

277.6 171.0

281.7 173.7

285.9 176.4

290.1 179.1

294.4 181.8

298.7 184.6

303.0 187.4

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

369.1 229.6

374.2 232.8

379.4 236.1

384.6 239.4

389.9 242.8

395.2 246.1

400.5 249.5

405.9 253.0

411.4 256.5

416.9 260.0

422.5 263.5

428.2 267.1

433.9 270.7

439.6 274.3

445.4 278.0

451.3 281.7

457.3 285.4

141

142

143

144

145

146

147

148

149

150

547.0 341.6

553.9 345.9

560.9 350.3

567.9 354.6

575.1 359.0

582.3 363.5

589.6 368.0

596.9 372.5

604.4 377.1

611.9 381.7

113.6 65.7

115.8 67.1

118.1 68.6

120.3 70.0

122.7 71.5

125.0 73.0

127.4 74.5

129.8 76.1

132.2 77.6

134.7 79.2

137.2 80.8

139.7 82.4

193.9 117.3

197.1 119.4

200.4 121.4

203.6 123.5

207.0 125.7

210.3 127.8

213.7 130.0

217.1 132.2

220.6 134.5

224.1 136.7

227.7 139.0

231.3 141.3

100

101

102

103

104

105

106

107

108

109

307.5 190.2

311.9 193.0

316.4 195.9

321.0 198.8

325.6 201.8

330.2 204.7

334.9 207.7

339.6 210.8

344.4 213.8

349.3 216.9

354.2 220.0

359.1 223.2

128

129

130

131

132

133

134

135

136

137

138

139

463.2 289.2

469.3 293.0

475.4 296.9

481.6 300.8

487.8 304.7

494.1 308.7

500.5 312.6

506.9 316.7

513.4 320.7

520.0 324.8

526.6 329.0

533.3 333.2

Lubrication

Electric shock hazard. Shut off all

WARNING

air should

to prevent fin and/or coil damages.

bend the fin edges and increase

performance or nuisance unit

CAUTION

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 with a water spray in a

direction opposite to airflow. Care must be

taken to prevent bending of the aluminum

fins on the copper tubes.

E-Coated Coil Cleaning

Documented routine cleaning of e-coated

coils is required to maintain coating

warranty coverage.

electrical power to the unit to avoid shock hazard or injury from rotating parts.

Surface loaded fibers or dirt should be removed prior to water rinse to prevent restriction of airflow. If unable to back wash the side of the coil opposite of the coils entering air side, then surface loaded fibers or dirt should be removed with a vacuum cleaner. If a vacuum cleaner is not available, a soft non-metallic bristle brush may be used. In either case, the tool should be applied in the direction of the fins. Coil surfaces can be easily damaged (fin edges bent over) if the tool is applied across the fins.

Use of a water stream, such as a garden hose, against a surface loaded coil will drive the fibers and dirt into the coil. This will make cleaning efforts more difficult. Surface loaded fibers must be completely removed prior to using low velocity clean water rinse.

A monthly clean water rinse is recommended for coils that are applied in coastal or industrial environments to help to remove chlorides, dirt, and debris. It is very important when rinsing, that water temperature is less than 130°F and pressure is 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.

High velocity water from a pressure washer or compressed only be used at a very low pressure

The force of the water or air jet may

airside pressure drop. Reduced unit

shutdowns may occur.

Quarterly cleaning is essential to extend

coils. These cleaners can be very

CAUTION

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.

Harsh chemicals, household bleach, or acid cleaners should not be used to clean outdoor or indoor e-coated

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.

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 H-

EC01.

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 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.

Evaporative-Cooled Condenser

Evaporative cooling equipment rejects heat by evaporating a portion of the recirculated water spray and discharging it from the unit with the hot, saturated air. As the spray water evaporates, it leaves behind the mineral content and impurities of the supply water. If these residuals are not purged from the water distribution system, they will become concentrated and lead to scaling,

corrosion, sludge build-up and biological

NOT PERMITTED. The control system must regulate the chemical feed.

WARNING

cooled condenser

must be thoroughly cleaned on a

of bacteria, including Legionella Pneumophila, to avoid the risk of

Do not attempt any

out.

WARNING

fouling.

A water treatment monitoring and control system has been furnished with this unit. Be sure to read the complete manual that has been furnished. All water treatment is a combination of bleed water and chemical treatment for proper control of the residuals and to prevent any biological contamination.

Batch-loading chemicals into the unit is

Severe Service

The following recommended maintenance procedures are basic requirements for normal operating environments. For severe operating conditions, the frequency of inspection and service should be increased. Air containing industrial and chemical fumes, salt, dust, or other airborne contaminates and particulates will be absorbed by the recirculating water system and may form solutions and deposits harmful to the products and personnel.

Safety

The recirculating water system contains chemical additives for water quality control and biological contaminants removed from the air by the washing action of the water. Personnel exposed to the saturated effluent, drift, or direct contact should use proper precaution. Proper location of the evaporative-cooled condenser requires good judgment to prevent the air discharge from entering fresh air intakes or to avoid allowing contaminated building exhaust from entering the condenser.

Figure 22 - Proper Unit Location

Follow local and national codes in locating the evaporative-cooled condenser but as minimum the evaporative-cooled condenser sump must be 15 feet from the nearest intake.

The evaporative-

regular basis to minimize the growth

sickness or death. Service personnel must wear proper personal protective equipment. service unless the fan motor is locked

Figure 23 - Improper Unit Locations

Performance

Improper location of the evaporative-cooled condenser may seriously degrade the capacity of the equipment. Make sure the equipment is located such that discharge air from the condenser does not enter the condenser air inlet.

Warranties

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

Condenser Tube Inspection

The coil is leak tested at 450 P.S.I.G. before shipment. AAON will not be responsible for loss of refrigerant. It is the responsibility of the installer to verify that the system is sealed before charging with refrigerant. If the unit is operated during low ambient temperature conditions, freeze protection for the recirculating water system must be provided.

Freeze Protection

In order to prevent water temperatures from dropping below 50°F, this unit is equipped

with a VFD on the fan motors when the refrigeration system is operating.

Recirculating Water System

Electric sump heaters are available to keep the sump water from freezing when the refrigeration system is not operating. An electric resistance heater is supplied in the vestibule when sump heaters are selected.

Note: The condenser should not be operated with the fan on and the pump cycled on and off to maintain head pressure control under any conditions. The unit is equipped with a water temperature controller which varies fan speed to maintain sump water temperature. This unit is not equipped with a compressor discharge pressure controller for fan speed modulation and therefore cannot be operated without water flow.

Startup

Do not start the evaporative-cooled condenser or compressors without installation of proper water treatment chemicals. Contact your local water treatment expert for correct selection of water treatment chemical, adjustment of chemical feed and bleed rates.

Cleanliness

Dirt and debris may accumulate in the sump during shipping and storage. The sump should be cleaned prior to startup to prevent clogging the water distribution system. Any surfaces that show contamination should be cleaned ONLY with a commercial stainless steel cleaner to restore the initial appearance. The inlet screens should be inspected for foreign material.

Storage

Pumps removed from service and stored, must be properly prepared to prevent excessive rusting. Pump port protection plates must not be removed until the pump is

ready to connect to the piping. Rotate the shaft periodically (At least monthly) to keep rotating element free and bearings fully functional.

For long term storage, the pump must be placed in a vertical position in a dry environment. Internal rusting can be prevented by removing the plugs at the top and bottom of the casing and drain or air blow out all water to prevent rust buildup or the possibility of freezing. Be sure to reinstall the plugs when the unit is made operational. Rust-proofing or packing the casing with moisture absorbing material and covering the flanges is acceptable. When returning to service be sure to remove the drying agent from the pump.

Pump Operation

Before initial start of the pump, check as follows:

1. Be sure that pump operates in the

direction indicated by the arrow on the pump casing. Check rotation each time motor leads have been disconnected.

2. Check all connections of motor and

starting device with wiring diagram. Check voltage, phase and frequency of line circuit with motor name plate.

3. Check suction and discharge piping and

pressure gauges for proper operation.

4. Turn rotating element by hand to assure

that it rotates freely.

Running

Periodically inspect pump while running, but especially after initial start-up and after repairs.

1. Check pump and piping for leaks. Repair

immediately.

2. Record pressure gauge readings for

future reference.

3. Record voltage, amperage per phase, and

kW.

Condenser Fan Motors

The direct drive condenser motors on AAON evaporative-cooled condensers are 1200 rpm premium efficiency motors controlled by a VFD. These motors are totally enclosed air over motors with weep holes in the bottom end bell so that any condensation can drain out of the motor.

The motors have a small electric resistance heater installed inside the casing to keep the motors warm when they are deactivated. The heaters are designed to keep the interior of the motor 10°F warmer than the surrounding ambient temperature. This prevents condensation from forming inside the motor.

Ensure that fan is tightly mounted to the motor shaft and the motor mounting bolts are aligned and secure.

Water Make Up Valve

The sump water level is controlled by a set of conductivity probes at different levels in the sump. This water level controller is located in the vestibule behind the condenser pump. There are four conductivity probes in this controller. There is a reference probe (shown as “ref” on the wiring diagram). This probe is one of the two longest probes. The other long probe is the low water level probe (shown as “lo” on the wiring diagram). The medium length probe is for the medium water level (shown as “med” on the wiring diagram). The short probe is for the high water level (shown as “hi” on the wiring diagram). There is a solenoid valve in the makeup water line that is activated by the water level controller. The water level controller determines the level of water in the sump based on conductivity between two probes. If the controller sees conductivity between two probes, it knows that water is at least at the level of that probe.

If the water in the sump is below the low probe, it will not allow the condenser pump or the sump heater to operate. It will activate the make-up water solenoid to try to fill the sump assuming water is flowing to the unit. Once water is above the low probe, it will allow the condenser pump and sump heater (if ordered and the ambient temperature is below 40°F) to operate. The make-up water solenoid will remain activated until water gets to the high water level. The make-up water solenoid will deactivate until water gets to the medium water level. In normal operation, the water level should swing between the medium and high water levels. The maximum high water level should be 1” below the overflow drain which occurs after the make-up water valve shuts off when the water level reaches the high level probe.

Figure 24 - Water Makeup Valve

Make up water supply pressure should be maintained between 15 and 60 psig for proper operation of the valve. The make-up water valve assembly should be inspected monthly and adjusted as required. Replace the valve seat if leakage occurs when the valve is in the closed position.

Water Treatment System

All AAON evaporative-cooled condensers come equipped with a water treatment system that should be maintained by a local water treatment professional trained in the water treatment of evaporative-cooled condensers. This system consists of a controller, three chemical pumps and storage tanks, a conductivity sensor, a motorized ball valve for water bleed and a water meter.

One chemical pump and tank is typically used for a de-scaling chemical to prevent scale from forming in the condenser. The other two pumps and tanks are typically used for two different biocides (to kill any microorganisms that could grow in the condenser). Two biocides are used to prevent organisms from becoming resistant to one chemical.

The mineral content of the water must be controlled. All make up water has minerals in it. As water is evaporated from the condenser, these minerals remain. As the mineral content of the water increases, the conductivity of the water increases. The water treatment controller monitors this conductivity. As the water conductivity rises above set point, the controller will open a motorized ball valve on the discharge side of the condenser pump and dumps water into the condenser drain until conductivity is lowered. While the motorized ball valve is opened, the controller will not disperse chemicals.

The chemicals are dispersed by the water treatment controller based on the scheduled input by the water treatment professional.

The water meter measures the quantity of makeup water used by the condenser.

Any water treatment program must be compatible with stainless steel, copper,

aluminum, ABS plastic and PVC. Batch feed processes should never be used as concentrated chemicals can cause corrosion. Never use hydrochloric acid (muriatic acid) as it will corrode stainless steel.

Sequence of Operation for LL Series units without Diagnostics

On a call for cooling, the condenser pump is activated. A pressure switch in the pump discharge is bypassed for six seconds by a time delay relay in order for the pump to establish recirculating water flow. If flow is not proven within the six seconds, the pressure switch opens, breaking the safety circuit, thereby shutting down the entire system. This pressure switch is set to close at 3 psi and open at 1 psi.

A Johnson Controls S350C measures the water temperature in the pump discharge line. If the sump water temperature exceeds 105°F, the cooling system will be shut down thereby preventing damage to the evaporative-cooled condenser.

If a fault occurs in the evaporative-cooled condenser fan motor VFD, normally closed fault terminals on the VFD will interrupt the safety circuit, thereby shutting down the system.

If the VFD does fault and cannot be reset, there is a VFD bypass switch mounted near the VFD. This switch has four positions— line, off, drive, and test. The “line” position will bypass the VFD, sending power to the motor. In this position, the condenser fans will run at full speed. The “off” position will not allow power to pass through the switch. This functions as a disconnect switch. The “drive” position runs power through the VFD. This is the normal operation for the switch. The “test” position routes power to the VFD but not to the motor. This is useful

for running tests on the VFD without sending power to the motor.

A Johnson Controls A350P controls the VFD speed. This device sends a 0-10 VDC signal to the VFD. This controller is set to maintain a sump temperature of 70°F. On a rise in sump temperature, the controller increases the voltage to the VFD, increasing the speed of the condenser fans. Conversely, on a drop in sump temperature, the controller will decrease the voltage to the VFD, decreasing the speed of the condenser fans.

An outside air thermostat does not allow the condenser to operate when the ambient temperature is below 35°F.

Sequence of Operation for LL Series units with Diagnostics

These units operate the same way as described in the previous section, except the unit controller operates the evaporativecooled condenser. These units can also operate down to 0°F when equipped with the flooded condenser option as described in the low ambient section.

On units with diagnostics, each refrigerant system has suction and discharge pressure transducers and suction and discharge temperature sensors. Each compressor has a current transformer. The condenser pump is the first stage of condenser control and the condenser fans are the second stage of condenser control. The unit controller brings on the condenser stages based on the discharge pressures of each system. The system with the highest pressure will control the condenser staging. The first stage of condenser will activate at 180 psig (R-22) and deactivate at 160 psig. The second stage of condensing will activate at 195 psig and deactivate at 185 psig. The unit controller

will change the speed of the VFD to maintain 195 psig.

The unit controller will monitor the sump temperature and if it exceeds 105°F, it will reduce the number of compressors that are running. The unit controller monitors the condenser pump pressure switch. If this switch opens, it will not allow the compressors to operate. The unit controller also monitors the VFD fault status. If it receives a VFD fault, it will activate the alarm contacts on the unit controller. The VFD will no longer run, but the compressors will run until the pressures or temperatures get too high. The controller will reduce the number of compressors to try to keep as much of the unit running as possible. The VFD bypass switch can be set to “line” to operate the condenser fans at full speed. Units with diagnostics can operate below 35°F down to 0°F. This is possible because of the finned de-superheat coil. When the ambient temperature is below 32°F, the condenser pump will not operate. As the ambient temperature increases, the condenser pump will activate at 35°F. As the ambient temperature decreases, the condenser pump will deactivate at 32°F. This dead band prevents the condenser pump from cycling too much. Below 32°F, the unit operates as an air-cooled condenser. An optional sump heater operates when the ambient temperature is below 40°F to prevent the sump from freezing and offers freeze protection to 0°F.

Pump Maintenance

Cleaning - Remove oil, dust, water, and chemicals from exterior of motor and pump. Keep motor air inlet and outlet open. Blow out interior of open motors with clean compressed air at low pressure.

Labeled Motors - It is imperative for repair of a motor with Underwriters’ Laboratories

label that original clearances be held; that all plugs, screws, other hardware be fastened securely, and that parts replacements be exact duplicates or approved equals. Violation of any of the above invalidates Underwriters’ Label.

Fan Motor Maintenance

Same as pump maintenance.

Access Doors

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

Bearings - Lubrication

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

Recommended Monthly Inspection

1. Clean sump section interior. Dirt and

other impurities which have accumulated in the sump should be removed from the sump area. Shut off make-up water ball valve and open the drain connection for flushing of the sump.

2. Clean dirt out of sump using a water

hose (not a pressure washer).

3. Clean sump suction strainer.

4. Check water operating level. Adjust float

as required.

5. Inspect fan motor(s) and water

circulation pump(s) and lubricate per the lubrication nameplate or manufacture’s recommendations.

6. Inspect axial fans and eliminators

removing any debris which may have accumulated during operation.

7. Inspect the water distribution system to

insure that nozzles and spray orifices are functioning correctly. The inspection

should be made with the circulation

6.5 to 9.0

Hardness as CaCO

500 PPM Max

Alkalinity as CaCO3

500 PPM Max

Total Dissolved Solids

Chlorides as NaCl

1500 PPM Max

Sulfates

750 PPM Max

pump on and fans off.

Mist Eliminators

The mist eliminators must be correctly positioned when they are replaced during cleaning or service.

Air Inlet

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

Stainless Steel Base Pan

The base pan under the tube bundles is stainless steel and may sometimes become tarnished due to contamination. These surfaces should be inspected yearly to ensure they remain clean of any contamination that may result in damage. Any surfaces that show contamination should be cleaned ONLY with a commercial stainless steel cleaner to restore the initial appearance.

Propeller Fans and Motors

The fans are directly mounted on the motor shafts and the assemblies require minimal maintenance except to assurance they are clear of dirt or debris that would impede the airflow.

Recommended Annual Inspection

In addition to the above maintenance activities, a general inspection of the unit surface should be completed at least once a year. Remove spray header and flush out.

Cleaning

Mechanical cleaning, including pressure washing, should never be performed as surfaces and seals could be damaged. Chemical cleaning that is safe for stainless steel, copper, aluminum, ABS plastic and PVC is the only acceptable means of

cleaning the evaporative condenser. A proper water treatment program should reduce cleaning needs.

Water Quality

Table 12 - Recirculating Water Quality

Guidelines

2000 PPM Max

Cycles of concentration (the ratio of dissolved solids in recirculated water to dissolved solids in makeup water), should be determined and monitored frequently by a competent water treatment expert. To limit cycles of concentration to maintain the above guideline, it is necessary to “bleed” a certain portion of the recirculated water. This is achieved automatically with a solenoid valve actuated by a conductivity meter set at the desired conductivity corresponding to the desired cycles of concentration. It should be noted that these are guidelines and even though these individual values are met, under certain conditions the water quality can be aggressive. For example, water with very low alkalinity and levels of chlorides and sulfates approaching maximum recommended levels can be corrosive.

All AAON evaporative-cooled condensers are furnished with a bleed system fitting and valve to continuously remove a small portion of the recirculated water to keep the water quality within the above listed parameters. This device is located on the discharge side of the pump. It is important to note that since “bleed” rate is a function of evaporation rate (i.e., amount of heat

rejected), if the bleed setting is manual based on design heat load, too much water will be removed when the heat load is less that design.

The AAON evaporative-cooled condenser is equipped with a de-superheater. The desuperheater coil is located above the mist eliminators. Approximately 22% of the total heat of rejection is accomplished with the de-superheater. Water usage of the AAON evaporative-cooled condenser is approximately 22% less than evaporativecooled condensers not equipped with a desuperheater.

One method of calculating evaporation and bleed in gallons per minute (gpm) is shown as follows:

Evaporation Rate

     







, ( )

 ×







×









Bleed Rate

 

    

Example:

A unit has 100 ton cooling capacity with a compressor EER = 15

Total Heat of Rejection

= Unit Capacity in Tons × 12000 ×󰇡1 +

3.413EER

= 100 × 12000 × 󰇡1 +

.



󰇢

= 1,473,040 Btu/hr

Total Full Load Heat of Rejection via Evaporation

= Total Heat of Rejection × (1 – fraction of heat rejected by desuperheater) = 1,473,040 Btu/hr × (1 – 0.22) = 1,148,971 Btu/hr

Note that approximately 22% of the total heat of rejection is accomplished with the de-superheater at full load. So, the fraction of heat rejected by the de-superheater (in the equation above) is approximately 0.22 at full load and increases as the ambient dry bulb decreases.

Evaporation Rate

)

,, ( 

, ( 



)



= 2.19 gpm

Assuming 4 cycles of concentration:

Bleed Rate

.



= 0.73 gpm

Mechanical Cleaning

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

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. Reference the unit serial number and part number when ordering parts.

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

Water Pressure Reducing Valve

Water Pressure Reducing Valves are designed to reduce incoming water pressure to protect plumbing system components and reduce water consumption.

Overview

Standard construction includes Z3 sealed spring cage and corrosion resistant adjusting cage screws for outdoor/waterworks pit installations

• Integral stainless steel strainer

• Replaceable seat module

• Bronze body construction

• Serviceable in line

• High temperature resistant reinforced

diaphragm for hot water

• Low pressure range 10 – 35psi (69 – 241

kPa)

Materials

Body: Bronze Seat: Replaceable stainless steel Integral Strainer: Stainless steel Diaphragm: Reinforced EPDM Valve Disc: EPDM

Standards

Meets requirements of ASSE Standard 1003; (ANSI A112.26.2); CSA Standard B356; Southern Standard Plumbing Code and listed by IAPMO. Teflon® is a registered trademark of E.I. Dupont de Nemours & Company.

Capacity

Maintenance Instructions

To clean strainer remove the bottom plug and pull out strainer.

Adjustment

To adjust pressure setting, loosen the lock nut and turn the adjusting bolt clockwise to increase pressure, counter clockwise to decrease pressure.

Dimensions-Weights:

Note: Use a pressure gauge downstream to

adjust and verify the pressure setting.

Troubleshooting High System Pressure

If the downstream system pressure is higher than the set pressure under no flow conditions, the cause could be thermal expansion, pressure creep or dirt/debris on the seat. Thermal expansion occurs whenever water is heated in a closed system. The system is closed when supply pressure exceeds 150 psi, or a check valve or backflow preventer is installed in the supply piping. To determine if this is the result of thermal expansion, try briefly opening the cold water tap. If the increased pressure is caused by thermal expansion, the pressure will immediately be relieved and the system will return to the set pressure.

Water Pressure Relief Valve

Overview

ASME Rated, Design Certified and Listed by C.S.A.

Used for protection against excessive pressure on domestic storage tanks or tankless water heaters, the pressure relief valve has no temperature relieving element.

Standard setting, 125 psi Size 3⁄4" x 3⁄4" (20mm x 20mm).

ASME construction and is tested, listed and certified by the National Board of Boiler and Pressure Vessel Inspectors.

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.

ANSI Z21.22 “Relief Valves for Hot Water Supply Systems.” DESIGN CERTIFIED and listed by C.S.A.

Automatic Air Vent Valves

Automatic Air Vent Valves provide 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

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

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.

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 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.

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

CAUTION

Dimensions – Weights:

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

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.

understood.

Where under normal operating conditions the limit of 68°C/155°F (Restricted Zone) for normal touch, or 80°C/176°F (Unrestricted Zone) for unintentional touch, may be experienced, steps should be taken to minimize contact or warn operators/users that normal operating conditions will be exceeded. In certain cases where the temperature of the pumped liquid exceeds the above stated temperature levels, pump casing temperatures may exceed 100°C/212°F and not withstanding pump insulation techniques appropriate measures must be taken to minimize risk for operating personnel.

Storage

Pumps removed from service and stored, must be properly prepared to prevent excessive rusting. Pump port protection plates must not be removed until the pump is ready to connect to the piping. Rotate the shaft periodically (At least monthly) to keep rotating element free and bearings fully functional.

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

CAUTION

Do not run pumps with discharge

CAUTION

Use Caution. Piping may carry high temperature fluid.

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

The discharge valve only is to be used to throttle pump flow, not the suction valve. Care must be taken in the suction line layout and installation, as it is usually the major source of concern in centrifugal pump applications

Alignment

Alignment is unnecessary on close-coupled pumps as there is no shaft coupling.

Split-coupled units are accurately aligned at the factory prior to being shipped and do not need re-aligning when installed.

Pump Operation

valve closed or under very low flow conditions.

Starting Pump

Ensure that the pump turns freely by hand, or with some mechanical help such as a strap and lever on larger pumps. Ensure that all protective guarding is securely fixed in position.

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

Check rotation arrow prior to

CAUTION

Electric shock hazard. Before

maintenance on pumping unit, disconnect power source to the

WARNING

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.

operating the unit.

Check rotation arrow prior to operating the unit. The rotation of all Vertical In-Line units is “clockwise” when viewed from the drive end. (Looking from on top of / behind the motor)

General Care

Vertical In-Line pumps are built to operate without periodic maintenance, other than motor lubrication on larger units. A systematic inspection made at regular intervals, will ensure years of trouble-free operation, giving special attention to the following:

• Keep unit clean

• Keep moisture, refuse, dust or other

loose particles away from the pump and ventilating openings of the motor.

• Avoid operating the unit in overheated

surroundings (Above 100ºF/40ºC).

attempting to perform any service or

driver, LOCK IT OFF and tag with the reason.

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.

Lubrication

Pump

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.

CAUTION

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 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.

Double Check Prior to Startup

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

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

taken when

WARNING

Care should be taken when

WARNING

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.

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

Locking

1. Loosen suction side set screw (11) to

release the locking handle (3).

2. Rotate the suction side locking handle

(3) so that the handle points towards the pump to be serviced and secure in the horizontal position, using set screw (11). This releases the suction locking arm (4).

Note: The locking handle (3) should only be rotated towards the pump stopped for service. The suction valve is designed to prevent the locking handle (1) from rotating towards the running pump, as the suction of the running pump could cause the valve to slam shut with sufficient force to injure the operator and/or cause damage to the pump. Do not attempt to circumvent this safety feature.

3. Rotate the suction valve towards the

pump to be isolated. The orientation of the shaft is indicated by the center pin on the locking arm (4).

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.

performing procedures 3 and 4. Read instructions carefully.

Unlocking

1. Open the interconnecting valve on the

seal flush line to pressurize the serviced pump and vent air through bleeder valve on series 4302. Close these valves once the pressure is equalized and air removed.

2. Loosen set screw (11) and lower locking

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

NOTE: Keep hands and tools away from suction valve locking arm when freed by locking handle as differential pressure may cause arm to rotate quickly with force when unlocked.

3. Rotate valve to center position so that

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

4. Loosen set screw (11) and raise locking

arm (3) to the vertical position, locking the center pin in the locking arm recess, secure with set screw.

4. Loosen set screw (11) and raise the

locking handle (3) so that the cam on the

Horizontal and Vertical Expansion Tanks

ASME PRE-PRESSURIZED DIAPHRAGM EXPANSION TANKS FOR HEATING & COOLING SYSTEMS

Vessel Description Tanks are ASME constructed and precharged. They are designed to absorb the expansion forces and control the pressure in heating/cooling systems.

The system’s expanded water is contained behind a heavy-duty diaphragm fully compatible with water/glycol mixtures preventing tank corrosion and water logging problems.

The factory set pre-charge for these tanks is

12 psig (83 kPa).

Materials

Shell – Carbon Steel Diaphragm – Heavy Duty Butyl

Operating Conditions

Maximum Working Temperature - 240°F (115°C) Maximum Working Pressure – 125 psi (862 kPa)

Maintenance Steps & Procedure

Visually inspect tank for damage, which may occur during transit.

Factory pre-charge pressure may not be correct for the installation. Tank MUST be pre-charged to system design fill pressure BEFORE placing into operation. Remove pipe plug covering the valve enclosure. Check and adjust the charge pressure by adding or releasing air for each application.

Note: If the system has been filled, the tank must be isolated from the system and the tank emptied before charging. This ensures

all fluid has exited the diaphragm area and proper charging will occur.

If the pre-charge adjustment is necessary, oil and water free compressed air or nitrogen gas may be used. Check the pre-charge using an accurate pressure gauge at the charging valve and adjust as required. Check air valve for leakage. If evident, replace the Schrader-type tire valve core.

Do not depend on the valve cap to seal the leak.

After making sure air charge is correct, replace pipe plug over the charging valve for protection.

Set tank in place and pipe system connection to system. Be sure to include isolation valve(s) and drain.

Purge air from system BEFORE placing tank into operation. All models have system water contained behind diaphragm.

When filling the system with water, open valves to tank to ensure that any residual air in the tank is displaced by water.

It is recommended that the pre-charge be checked annually to ensure proper system protection and long life for the vessel.

Installation

The Suction Guides may be installed in any arrangement feasible the arrangement of the pump flange bolt-holes.

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.

Inspection

Suction Guides are thoroughly tested and inspected before shipment to assure they meet with your order requirements. All units must be carefully examined upon arrival for possible damage during transit. Any evidence of mishandling should be reported immediately to the carrier and noted on the freight bill.

Operation

No special attention need be paid to the Suction Guide at start-up. The fitting is stationary and will strain the pumped fluid and stabilize the flow into the pump automatically.

Temporary strainer must be removed following system clean up.

After all debris has been removed from the system, or a maximum of 24 running hours, stop the pump and close the pump isolation valves. Drain the Suction Guide by removing the drain plug or opening the blowdown valve, if installed

Remove the Suction Guide cover and remove the strainer assembly from the valve body.

A temporary fine-mesh start-up strainer is tack-welded to the permanent stainless steel strainer. This temporary strainer should now be removed from the permanent strainer. The fine-mesh strainer is designed to remove small particulate from new piping systems and could easily clog with debris if left in place. This will be detrimental to the operation of the pump.

Inspect the cover O-ring and replace if necessary.

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.

Glycol Auto Fill Unit

The glycol auto fill unit (GLA) is designed to maintain the HVAC system pressure by adding the appropriate mix of glycol and water to the system. During the normal operation of the HVAC system, fluid is lost causing a drop in the system pressure.

Standard Unit

Ultra Unit

When the system pressure drops below the set point on the pressure switch, the GLA pump is started adding fluid from the GLA tank into the HVAC system. When the system pressure returns to normal operating conditions, the pump stops. As the tank empties, a level switch is actuated lighting the low level pilot light. If the system is not filled, a second level switch stops the pump(s) preventing the pump(s) from running dry. Should the system be overfilled, a high level alarm is actuated by level switch. Dry contacts can be provided for remote indication of the above conditions.

A manual “push to mix” switch is provided for agitation of the contents of the GLA unit. The switch starts the pump and opens the return line solenoid valve circulating the fluid.

Duplex units are equipped with a manual alternator to equalize wear on the pumps.

Essential Safety Requirements

Glycol is toxic and the glycol supplier’s safety instructions must be adhered to. In critical areas a retaining wall should be used to contain any spillage or leakage. Overflows should be arranged not to contaminate drainage systems.

It is recommended that initial commissioning be carried out with water.

The flow rates from the unit are designed for make-up rates. It is therefore suggested that the system is back-filled with due precautions taken to avoid contamination.

Glycol is sometimes subject to bacterial attack and can become slimy as a result. AAON recommend the addition of a suitable biocide. The dosage should be calculated on the amount of water glycol mixture added and not the total tank contents. If bacterial attack occurs on untreated mixtures the unit should be drained, flushed and refilled with fresh mixture and dosed with biocide.

Check that the supply voltage and overload protection is correct.

Guards and covers must not be removed during operation.

The pipework from the system to the expansion vessels should not be insulated.

For systems operating above 200°F (93°C), an anti-gravity loop with a minimum height of 6 feet, (or an intermediate vessel) should be installed to provide thermal protection to the expansion tanks.

The ball float valve is fitted with a lowpressure seat; a high-pressure seat is attached to the float valve and should be fitted if required.

Pressure Switch Adjustment

Low system pressure – PS1 High system pressure – PS2 Duty pump control switch – PS3 Standby pump control switch (where fitted) – PS4

For each switch, set the delivery to the required pressure. Then very slowly turn the adjusting screw on the switch until the contacts change.

The high system pressure switch should first be set higher than the required pressure by turning the screw clockwise and the setting then made by turning the screw counterclockwise until the switch contacts changeover.

The other switches should first be set lower than the required pressure by turning the screw counter-clockwise and the setting then made by turning the screw clockwise until the switch contacts changeover.

A pipe plug is provided on the outlet to allow connection of a test pump to simulate differing system pressures to check switch settings.

The Ultra versions of the GLA have the capability of controlling duty and standby pumps from a single pressure switch.

GLA Ultra Settings

The extra functionality of Ultra units is integral. The only selectable option is Manual or Automatic reset of alarm conditions. DIP switch 1, on the display board should be set to OFF for auto reset (Factory setting), and ON for manual reset. On alarm conditions, the MUTE switch will mute the buzzer. In manual reset mode this MUTE switch will reset the alarms after the fault condition has been cleared. Other switches change the mode of the printed circuit board for use with other products. For GLA application, all switches except 1 and 7 must be set to OFF.

Priming the makeup pumps:

1. Close suction isolating valve.

2. Fill the glycol-mixing tank.

3. Remove the upper vent plug from the

makeup pump.

4. Open suction isolation valve until water

flows out of this tapping.

5. Close valve and replace plug.

6. Repeat for standby pump (where fitted).

7. Close the system-isolating valve.

8. Open suction isolating valve.

9. Switch on unit, initially both pumps will

run. As the pressure reaches the pump control switch threshold, the pumps will switch off.

10. Check all piping for leaks following

shipping.

11. Crack open system valve. The pressure

will fall and the pump will start and maintain pressure.

Powered agitation (Ultra model only):

A solenoid valve is fitted to provide powered agitation of the mixture. Automatically this valve is periodically opened and the duty pump starts creating circulation through the pump and mixing tank. Automatic mixing is inhibited when there is a system demand for make-up. A switch is provided for manual agitation when adding glycol to the mixing tank.

Topping up with glycol:

The mixing tank is calibrated in liters and US gallons. The normal top up level is 53 US gallons (200 liters).

1. Calculate the amount of water needed

and add or drain to the correct level.

2. Add the required amount of glycol.

3. Operate the manual-agitating switch.

4. Check the mixture percentage. The unit is now ready for service.

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).

Table A1. Armgrip Flange Adapter Details

Ductile Iron Bolt

No.

Size

No.

Size

5/8 8 3/4 5 8

3/4 8 3/4

7/8

1-1/8

125 psi/150 psi 250 psi/300 psi

Valve Size

2-1/2 4 5/8 8 3/4

3 4 5/8 8 3/4

6 8 3/4 12 3/4 8 8 3/4 12 7/8

10 12 7/8 16 1

The gasket cavity should face out to the adjoining flange.

2. Lubricate the inner and outer diameter of

the gasket with the lubricant provided or a similar non-petroleum based water soluble grease.

3. Press the gasket firmly into the flange

cavity ensuring that the sealing lip is pointed outward. When in place, the gasket should not extend beyond the end of the pipe (as shown).

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.

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.

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

Valve Size

2-1/2

3 4 5 6 8

Number of

Rings

(valve fully

Safety glasses should be worn. Probes should not be left inserted

CAUTION

pressure across the valve.

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.

into fittings for long periods of time as leakage may result.

Step 2. With valve in fully open position, locate the differential pressure on the Performance curve, and for the given valve size in use, read the corresponding flow rate.

Flow Measurement with the valve in the throttled position

Step 1. The valve stem with its grooved

rings and positioning sleeve is the flow indicator scale for the throttled position of the valve.

open)

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

5 5 6 9 10 12 18 28

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

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.

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

100

34) x (400

100

34) x (25.2

CAUTION

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 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.

‘’

Safety glasses should be worn.

Step 1. Record the valve setting.

Step 2. Turn the valve stem

counterclockwise until the valve is fully open and will not turn any further. Torque to

a maximum of 45 ft-lbs. This will ensure good metal to metal contact and minimal leakage.

Step 3. The valve bonnet may now be removed. There may be a slight leakage, as the metal to metal backseating does not provide a drip-tight seal.

Step 4. Clean exposed portion of valve stem being careful not to leave scratches.

Step 5. Remove and replace the O ring gasket.

Step 6. Install the valve bonnet.

Step 7. Tightening the valve bonnet is

necessary to stop any leaks.

Step 8. Open valve to balance set point as recorded in Step 1.

Note: On valve sizes of 2-1/2 inch and 3 inch, the full open position is 5 turns, though the valve will open to 5-1/2 turns which is just back of seating of valve.

Seat Replacement Step 1. Drain the system and remove valve

from piping.

Step 2. Remove the body bolts from the body using an Allen Key.

Step 3. Remove seat and O Ring. O rings are not used on valves of 8 inches or larger.

Step 4. Inspect and clean O ring cavity and install new O ring and seat. Valve disc stem should be inspected and replaced if worn. Valve stem O ring should be replaced at this time as discussed under Repacking of FloTrex section.

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

LL Series Startup Form

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

Job Name:_______________________________________________

Date:______________

Pre Startup Checklist

Ambient Temperature

Ambient Dry Bulb Temperature ________°F

Ambient Wet Bulb Temperature ________°F

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. Have isolation valves to the boiler been installed?

Yes No

4. Has the entire system been filled with fluid?

Yes No

5. Has air been bled from the heat exchangers and piping?

Yes No

6. Is there a minimum load of 50% of the design load?

Yes No

7. Has the water piping been insulated?

Yes No

8. Is the glycol the proper type and concentration (N/A if water)?

Yes No

Air-Cooled Condenser

Evaporative-Cooled Condenser

Low Ambient Control

Condenser Safety Check

No Water Leaks

Water Flow ________ gpm

Chilled Water In Temperature ________°F

Chilled Water Out Temperature ________°F

Boiler Safety Check

Boiler Building Water Flow ________ gpm

9. What is the freeze point of the glycol (N/A if water)? ______________________________

Chiller Configuration

Boiler Configuration

No Water Leaks

Boiler Water Flow ________ gpm

Compressors/DX Cooling

Check Rotation

Head

Suction

Crankcase

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Number Model # L1 L2 L3

Refrigeration System 1 - Cooling Mode

Pressure

PSIG

Pressure

PSIG

Heater

Amps

Pressure

Refrigeration System 2 - Cooling Mode

Pressure

Refrigeration System 3 - Cooling Mode

Pressure

Sub-cooling Superheat

Refrigeration System 4 - Cooling Mode

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Line

Discharge

N/A

Suction

N/A

Liquid

N/A

Saturated

Temperature

Line

Temperature

Discharge

N/A

Suction

N/A

Liquid

N/A

Refrigeration System 5 - Cooling Mode

Refrigeration System 6 - Cooling Mode

Refrigeration System 7 - Cooling Mode

Pressure

Sub-cooling Superheat

Refrigeration System 8 - Cooling Mode

Pressure

Temperature

Sub-cooling Superheat

Condenser Fans

Number

Flow (gpm)

Chiller Pump #3

Chiller Building Pump #1

Chiller Building Pump #2

Boiler Building Pump #1

Boiler Building Pump #2

Alignment

Condenser Pumps

Check Rotation

Nameplate Amps________

Check Rotation

Pumping Package

Chiller Pump #1

Chiller Pump #2

Chiller Pump #4

Boilers

Boiler

Amps

Boiler

Amps 1 3 2 4

Boiler Water In Temperature ________°F

Boiler Water Out Temperature ________°F

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

June 2010

Revision of the IOM adding PVC and CPVC piping Caution.

November 2010

Revision of the IOM changing the recommended superheat values to 10-15°F and adding a note that superheat on tandem compressors should be measured with only one compressor in the tandem running.

August 2011

Revision of the IOM adding information about the variable capacity oil-free magnetic bearing centrifugal compressor option, specifying that electronic expansion valves are available, and adding the electronic startup form.

November 2011

Revision of the IOM adding information about the variable capacity VFD controlled scroll compressor options.

March 2012

Revision of the IOM correcting the minimum inlet gas pressure for the 500 MBH boiler to 5” w.c and the 750, 1000, and 1500 MBH boiler to 7” w.c.

April 2012

Revision of the IOM adding the index of tables and figures and updating the table of contents.

June 2012

Revision of the IOM adding the caution about POE and PVE refrigeration system lubricants.

November 2012

Update of the IOM adding information about compressor cycling.

July 2013

Update of the format of the Feature String Nomenclature and revision of the left warning on cover.

October 2013

Added cautions calling for the need to seal water, electrical, and gas entries into the unit.

AAON

2425 South Yukon Ave.

Tulsa, OK 74107-2728

Phone: 918-583-2266

Fax: 918-583-6094

www.aaon.com

LL Series

Installation, Operation &

Maintenance

R10100 · Rev. B · 140226

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 LL-035 Installation Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Safety

LL Series Feature String Nomenclature

General Information

Codes and Ordinances

Receiving Unit

Storage

Outdoor Mechanical Room

Wiring Diagrams

General Maintenance

Chiller Primary Pumping

Chiller Primary/Secondary Pumping

Boiler System

Boiler Primary/Secondary Pumping

Make Up Water

Compression/Expansion Tank

Pressure Relief Valve

Automatic Air Vent

Dual Pumps

Pressure Gauges and Thermometers

Pipe Insulation

Installation

Outdoor Mechanical Room Placement

Curb and Steel Mount Installation

Lifting and Handling

Water Connection

Gas Connection

Boiler Exhaust Connection

Boiler Intake Connection

Mounting Isolation

Access Doors

Low Ambient Operation

LAC Valve

OROA Valve

ORI/ORD Valves

Condenser Flooding

Electrical

Startup

Axial Flow Condenser Fans

General

Compressors

Refrigerant Filter Driers

Evaporator/Heat Exchangers

Adjusting Refrigerant Charge

Lubrication

Air-Cooled Condenser

E-Coated Coil Cleaning

Recommended Coil Cleaner

Recommended Chloride Remover

Evaporative-Cooled Condenser

Severe Service

Safety

Performance

Warranties

Condenser Tube Inspection

Freeze Protection

Recirculating Water System

Startup

Cleanliness

Storage

Pump Operation

Running

Condenser Fan Motors

Water Make Up Valve

Water Treatment System

Sequence of Operation for LL Series units without Diagnostics

Sequence of Operation for LL Series units with Diagnostics

Pump Maintenance

Fan Motor Maintenance

Access Doors

Bearings - Lubrication

Recommended Monthly Inspection

Mist Eliminators

Air Inlet

Stainless Steel Base Pan

Propeller Fans and Motors

Recommended Annual Inspection