© American Standard Inc. 2005

Packaged Air-Cooled Chiller, RTAA 70-125

Remote Evaporator

Air-Cooled Chiller, RTAA 70-125

Models RTAA

RTAA-70

RTAA-80

RTAA-90

RTAA-100

RTAA-110

RTAA-125

Installation Operation Maintenance Series R®

Air-Cooled Rotary Liquid Chillers September 2005 RTAA-SVX01A-EN

Important

Environmental Concerns!

Scientific research has shown that certain man-made chemicals can affect the earth’s naturally occurring stratospheric ozone layer when released to the atmosphere. In particular, several of the identified chemicals that may affect the ozone layer are refrigerants that contain Chlorine, Fluorine and Carbon (CFCs) and those containing Hydrogen, Chlorine, Fluorine and Carbon

(HCFCs). Not all refrigerants containing these compounds have the same potential impact to the environment. Trane advocates the responsible handling of all refrigerants—including industry replacements for CFCs such as and HCFCs and HFCs.

Responsible Refrigerant Practices!

Trane believes that responsible refrigerant practices are important to the environment, our customers, and the air conditioning industry. All technicians who handle refrigerants must be certified. The Federal Clean Air Act (Section 608) sets forth the requirements for handling, reclaiming, recovering and recycling of certain refrigerants and the equipment that is used in these service procedures. In addition, some states or municipalities may have additional requirements that must also be adhered to for responsible management of refrigerants. Know the applicable laws and follow them.

� WARNING

Contains Refrigerant!

System contains oil and refrigerant under high pressure. Recover refrigerant to relieve pressure before opening the system. See unit nameplate for refrigerant type. Do not use non-approved refrigerants, refrigerant substitutes, or refrigerant additives.

Failure to follow proper procedures or the use of non-approved refrigerants, refrigerant substitutes, or refrigerant additives could result in death or serious injury or equipment damage.

NOTICE: Warnings and Cautions appear at appropriate sections through-out this literature. Read these carefully.

� WARNING: Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

� CAUTION: Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury. It may also be used to alert against unsafe practices.

CAUTION: Indicates a situation that may result in equipment or property-damage only accidents.

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Table of Contents

General Information

Unit Identification - Nameplates Nameplates Unit Inspection Inspection Checklist Loose Parts Inventory Unit Description Model Number Coding System

Installation — Mechanical

Installation Responsibilities Storage Location Requirements Foundation Clearances Rigging Unit Isolation Unit Leveling Water Piping Evaporator Water Piping Evaporator Piping Components Entering Chilled Water Piping Evaporator Drain Chilled Water Flow Switch

Installation — Remote Evaporator

System Configuration and Interconnecting Refrigerant Piping Line Sizing Example Liquid Line Sizing Suction Line Sizing Steps Piping Installation Procedures Refrigerant Sensors Leak Test and Evacuation Refrigerant and Additional Oil Charge Relief Valve Venting

Installation — Electrical

General Recommendations Installer-Supplied Components Power Supply Wiring Interlock Wiring Low Voltage Wiring Remote Clear Language Display Installation Procedure

Operating Principles

Refrigeration (Cooling) Cycle Oil System Operation

Controls Interface

Clear Language Display Keypad Overview Select Report Group and Select Settings Group Flowcharts Diagnostics Operational Features

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Table of Contents

DIP Switch Settings IPC Address

Pre-Start Checkout

Unit Voltage Power Supply Unit Voltage Imbalance Unit Voltage Phasing Water System Flow Rates Water System Pressure Drop Clear Language Display Set-up

Start-Up Procedures

System Superheat System Subcooling

Unit Shutdown Procedures

Temporary Shutdown and Restart Extended Shutdown Procedure System Restart After Extended Shutdown

Periodic Maintenance

Weekly Maintenance Monthly Maintenance Annual Maintenance

Maintenance

Coil Cleaning Chemically Cleaning The Evaporator Water Treatment Oil Separator Level Check Oil Filter Change

Refrigerant Charging and Recovery

Low Side Repairs High Side Repair Adding Refrigerant

Diagnostics

Pump Package

Temporary Storage Piping Pre-Start Review and Inspection Control Panel Features and Options Connection Power Pump Checkout Procedure Control Panel Checkout System Start-up Planned Shutdown Maintenance Troubleshooting

Unit Wiring

Unit Electrical Data

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General Information

Unit Identification - Nameplates When the unit arrives, compare all nameplate data with ordering, submittal, and shipping information. A typical unit nameplate is shown in Figure 1.

Nameplates The RTAA outdoor unit nameplates are applied to the exterior of the Control Panel. A compressor nameplate is located on each compressor.

Outdoor Unit Nameplate

The outdoor unit nameplate provides the following information:

Unit model and size description.

Unit serial number.

Identifies unit electrical requirements.

Lists correct operating charges of R-22 and oil.

Figure 1 Standatd Unit Nameplate

Figure 2 Pump Package Unit Nameplate

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Lists unit test pressures.

Identifies installation, operation and maintenance and service data literature.

Lists drawing numbers for unit wiring diagrams.

Pump Package Information - Optional

Compressor Nameplate

The compressor nameplate provides following information:

Compressor model number.

Compressor serial number.

Compressor electrical characteristics.

Utilization range.

Recommended refrigerant.

Unit Inspection When the unit is delivered, verify that it is the correct unit and that it is properly equipped. Compare the information which appears on the unit nameplate with the ordering and submittal information.

Inspect all exterior components for visible damage. Report any apparent damage or material shortage to the carrier and make a “unit damage” notation on the carrier's delivery receipt. Specify the extent and type of damage found and notify the appropriate Trane Sales Office.

Do not proceed with installation of a damaged unit without sales office approval.

NOTE: If the Remote Evaporator Option is ordered, the remote evaporator will be shipped in a separate crate.

Inspection Checklist To protect against loss due to damage incurred in transit, complete the following checklist upon receipt of the unit.

• Inspect the individual pieces of the shipment before accepting the unit.

Check for obvious damage to the unit or packing material.

• Inspect the unit for concealed damage as soon as possible after delivery and before it is stored. Concealed damage must be reported within 15 days after receipt.

• If concealed damage is discovered, stop unpacking the shipment. Do not remove damaged material from the receiving location. Take photos of the damage. The owner must provide reasonable evidence that the damage did not occur after delivery.

• Notify the carrier’s terminal of the damage immediately, by phone and by mail. Request an immediate, joint inspection of the damage with the car-rier and the consignee.

• Notify the Trane sales representative and arrange for repair. Do not repair the unit, however, until damage is inspected by the transportation repre-sentative.

Loose Parts Inventory Check all the accessories and loose parts which are shipped with the unit against shipping list. Included in these items will be water vessel drain plugs, isolators, rigging and electrical diagrams, and service literature, which are placed inside the control panel and/or starter panel for shipment.

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Unit Description The 70 through 125-ton Model RTAA units are helical-rotary type, air-cooled liquid chillers designed for installation outdoors. The unit has two compressors and the compressor circuits are completely assembled, hermetic packages. They are factory-piped, wired, leak-tested, de-hydrated, and tested for proper operation before shipment. The units are factory charged with refrigerant and oil.

The RTAA series features Trane's exclusive Adaptive Control™ logic with Clear Language Display. It monitors the control variables that govern the operation of the chiller unit. Adaptive Control logic can adjust these variables, when necessary, to optimize operational efficiencies, avoid chiller shutdown, and keep producing chilled water. An optional remote display is available to monitor unit operation from a remote location.

These dual-compressor units feature two independent circuits, one for each compressor. Compressor unloaders are solenoid actuated. Each refrigerant circuit is provided with filter drier, sight glass, electronic expansion valve, and charging valves.

The shell-and-tube type evaporator is manufactured in accordance with ASME standards. The evaporator is fully insulated and is equipped with water drain and vent connections. Packaged units have heat tape protection to -20 F.

NOTE: Packaged units are factory charged with refrigerant and oil. Remote evaporator units are shipped with a holding charge of nitrogen and a partial charge of oil.

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Table 1 General RTAA Mechanical Specifications

Size

70 80 90 100 110 125

Compressor

Quantity 2 2 2 2 2 2 Nominal Size (Tons)(1) 35/35 40/40 50/40 50/50 60/50 60/60

Evaporator

Water Storage (Gallons) 39.8 37.8 34.4 32.1 53.4 45.8 (Liters) 150.6 143.1 130.2 121.5 202.1 173.4

Min. Flow (GPM) 84 96 108 120 132 150 (L/Sec) 5.3 6.1 6.8 7.6 8.3 9.5

Max. Flow (GPM) 252 288 324 360 396 450 (L/Sec) 15.9 18.2 20.4 22.7 25.0 28.4

Refer to Pump Package Section for water storage of Pump and accocated piping.

Condenser

Qty of Coils 4 4 4 4 4 4 Coil Length (Ft)(1) 13/13 13/13 14/13 14/14 17/14 17/17 Coil Height (In) 42 42 42 42 42 42 Number of Rows 2 2 2 2 2 2

Condenser Fans

Quantity (1) 4/4 4/4 5/4 5/5 5/5 5/5 Diameter (In) 30 30 30 30 30 30 Total Airflow (CFM) 68,380 68,380 73,365 78,355 82,950 87,550 Nominal RPM 855 855 855 855 855 855 Tip Speed (Ft./Min.) 6715 6715 6715 6715 6715 6715 Motor HP (Ea.) 1.1 1.1 1.1 1.1 1.1 1.1

Min. Starting/Oper. Ambient

Std Unit (Deg. F) 15 15 15 15 15 15 Low Amb. (Deg. F) -10 -10 -10 -10 -10 -10

General Unit

Refrigerant HCFC-22 HCFC-22 HCFC-22 HCFC-22 HCFC-22 HCFC-22 No. of Independent Refrigerant Circuits 2 2 2 2 2 2 % Min. Load (3) 10 10 10 10 10 10 Refrig Charge (Lb) (1) 58/58 61/61 73/61 73/73 98/73 98/98

(Kg) 26/26 27/27 33/27 33/33 44/33 44/44 Oil Charge (Qts) (1.4) 10/10 10/10 12/10 12/12 12/12 12/12

(L) 10.6/10.6 10.6/10.6 12.7/10.6 12.7/12.7 12.7/12.7 12.7/12.7

Notes:

1. Data containing information on two circuits shown as follows: ckt1/ckt2

2. Minimum start-up/operating ambient based on a 5 mph wind across the condenser.

3. Percent minimum load is for total machine, not each individual circuit.

4. Trane Part Change # Oil-31 (see service bulletin SCOM-SB-1)

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Model Number Coding System The model number for the unit is comprised of numbers and letters which represent features of the equipment. Shown on the chart in Figure 3 are samples of typical unit model numbers, followed by the coding system.

Each position, or group of positions, in the number is used to represent a feature. For example, in Figure 3, position 8 of the unit model number, Unit Voltage, contains the number “4”. From the chart, it can be seen that a “4” in this position means that the unit voltage is 460/60/3.

Figure 3 Model Number Coding System:

Model Number RTA A 070 4 Y A0 1 B 1 D A 0

Digit Number 0 1 2

Digit Position 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 0

Digit 1-2

Unit Model

RT Rotary Chiller

Digit 3

Unit Type

A Air Cooled

Digit 4

Development Sequence

A First Sequence

Digit 5,6,7

Nominal Capacity

070 70 Nominal Tons 080 80 Nominal Tons 090 90 Nominal Tons 100 100 Nominal Tons 110 110 Nominal Tons 125 125 Nominal Tons

Digit 8

Unit Voltage

D 380/60/3 A 200/60/3 C 230/60/3 K 400/50/3 4 460/60/3 5 575/60/3

Digit 9

Compressor Starter Type

Y Y -Delta Closed Transition X X-Line (Across the Line)

Digit 10, 11

Design Sequence

AO First Sequence (Factory Input)

Digit12

Evaporator Leaving Temperature

1 Standard 40 to 65 F 2 Low 0 to 39 F 3 Ice-Making 20 to 65 F Digit 13

Condenser Coil Fin Material

A Aluminum 2 CompleteCoat dipped coils 4 copper fins

Digit 14

Agency Listing

0 No Agency Listing 3 C-UL Listed

Digit 15

Control Interface

C Deluxe without Communication D Deluxe with Communication L LCI-C (LonTalk)

Digit 16

Chilled Water Reset

0 No Chilled Water Reset 1 Based on Return Water Temp 2 Based on Outside Air Temp

Digit 17

Miscellaneous Factory Installed

Options

A Architectural Louvered Panels B Control Power Transformer C Convenience Outlet D Low Ambient Lockout Sensor F Power Disconnect G Low Ambient Operation H Sound Attenuator J Remote Evaporator K Coil Protection M Access Guard N Neoprene Isolators P Circuit Breaker R Remote Display Panel 0 Size C 2 HP Pump Package 1 Size D 3 HP Pump Package 2 Size D 5 HP Pump Package 3 Size E 2 HP Pump Package 4 Size E 3 HP Pump Package 5 Size F 5 HP Pump Package 6 Size F 7 HP Pump Package 7 Size G 3 HP Pump Package 8 Size G 5 HP Pump Package

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Installation — Mechanical

Installation Responsibilities Generally, the contractor must do the following when installing an RTAA unit:

• Install unit on a flat foundation, level (within 1/4” [6 mm] across the length and width of the unit), and strong enough to support unit loading.

• Install unit per the instructions contained in the Installation-Mechanical and Installation-Electrical sections of this manual.

• Where specified, provide and install valves in water piping upstream and downstream of evaporator water connections to isolate the evaporator for maintenance, and to balance/trim system.

• Furnish and install flow switch to prove chilled water flow.

• Furnish and install pressure gauges in inlet and outlet piping of the evapo-rator.

• Furnish and install a drain valve to the bottom of the evaporator.

• Supply and install a vent cock to the top of the evaporator.

• Furnish and install strainers ahead of all pumps and automatic modulating valves.

• Provide and install field wiring.

• Install heat tape and insulate the chilled water lines and any other por-tions of the system, as required, to prevent sweating under normal oper-ating conditions or freezing during low ambient temperature conditions.

• Start unit under supervision of a qualified service technician.

For remote evaporator units only

Furnish and install refrigerant piping, liquid line isolation valves, refrigerant, and oil, per instructions outlined in this manual.

Storage Extended storage of the outdoor unit prior to installation requires the following precautionary measures:

Store the outdoor unit in a secure area.

At least every three months (quarterly), check the pressure in the refrigerant circuits to verify that the refrigerant charge is intact. If it is not, contact a qualified service organization and the appropriate Trane sales office.

Close the discharge and liquid line isolation valves.

Location Requirements

Noise Considerations

• Refer to Trane Engineering Bulletins for application information on RTAA chillers.

• Locate the outdoor unit away from sound-sensitive areas.

• If required, install rubber vibration isolators in all water piping and use flexible electrical conduit.

• Refer to “Unit Isolation”.

• Consult an acoustical engineer for critical applications.

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Foundation Provide rigid, non-warping mounting pads or a concrete foundation of suffi-cient strength and mass to support the outdoor unit operating weight (i.e., including completed piping, and full operating charges of refrigerant, oil and water). Refer to Figure 13 for unit operating weights. Once in place, the outdoor unit must be level within 1/4” (6.4 mm) over its length and width. The Trane Company is not responsible for equipment problems resulting from an improperly designed or constructed foundation.

RTAA-SVX01A-EN 11

Figure 4 RTAA Rigging and Lifting Weights – Packaged Unit

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Figure 5 RTAA Rigging and Lifting Weights – Remote Evaporator

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Figure 6 RTAA Rigging and Lifting Weights –Pump Package Aluminum Fins

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Figure 7 RTAA Rigging and Lifting Weights –Pump Package Copper Fins

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Clearances Provide enough space around the outdoor unit to allow the installation and maintenance personnel unrestricted access to all service points. Refer to submittal drawings for the unit dimensions, to provide sufficient clearance for the opening of control panel doors and unit service. Refer to Figure 8, Figure 9 and Figure 12 for minimum clearances. In all cases, local codes which require additional clearances will take precedence over these recommenda-tions.

NOTE: If the outdoor unit configuration requires a variance to the clearance dimensions, contact your Trane Sales Office Representative. Also refer to Trane Engineering Bulletins for application information on RTAA chillers.

Additional Location Requirements for Remote Evaporator Only

The Remote evaporator must be installed in a conditioned space, unless:

• The ambient temperature is always greater than 32 F.

• The system circulating liquid is a non-freezing glycol-type solution, selected for the prevailing ambient temperature. The evaporator is protected from freezing by properly installed and applied insulation and heat tape.

CAUTION

Freezing Equipment Damage!

To prevent damage due to freezing, do not install the unit outside without adequate freeze protection.

The remote evaporator should be mounted on a base of suitable strength to support the operating weight. Remote evaporator weights and mounting locations are shown in Figure 10 and Figure 11.

The remote evaporator must be level when installed. Be sure to allow adequate clearance for water and refrigerant piping connection, performance of service procedures, reading of gauges and thermometers, and operation of valves. Space must be allowed at one end of the evaporator to pull tubes, if required.

Rigging The Model RTAA chiller should be moved by lifting. Refer to Figure 4 for typical unit lifting and weights. Refer to the rigging diagram that ships with each unit for specific “per unit” weight data.

� WARNING

Heavy Objects!

Do not use cables (chains or slings) except as shown. Each of the cables (chains or slings) used to lift the unit must be capable of supporting the entire weight of the unit. Lifting cables (chains or slings) may not be of the same length. Adjust as necessary for even unit lift. Other lifting arrangements may cause equipment or property-only damage. Failure to properly lift unit may result in death or serious injury. See details below.

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Lifting Procedure

CAUTION

Equipment Damage!

To prevent damage do not use a forklift to lift or push the unit.

Position lifting beam so that cables do not contact the unit.

• Install chains and safety chains through the six lifting plates provided on the unit.

• Attach lifting chains or cables to the chains installed above. Each cable alone must be strong enough to lift the chiller.

• Attach cables to lifting beam. Total lifting weight, lifting weight distribution and required lifting beam dimensions are shown in Figure 4 and Figure 5 and on the rigging diagram shipped with each unit. Lifting beam cross-bars must be positioned so lifting cables do not contact the sides of the unit.

RTAA-SVX01A-EN 17

F igure 8 Dimensions and Clearances for RTAA Packaged Unit 70 – 125 Tons

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Figure 9 Dimensions and Clearances for RTAA with Remote Evaporator 70 – 125 Tons

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Figure 10 Remote Evaporator Dimensions, RTAA 70 – 125 Tons

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Figure 11 Remote Evaporator Dimensions, RTAA 110 – 125 Tons

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Figure 12 Dimensions and Clearances for RTAA with Pump Package 70 – 125 Tons

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Unit Isolation There are two mounting methods that will minimize sound and vibration problems. They are the direct-mount method and the isolator-mount method.

Direct Mounting

The unit can be direct-mounted on an isolated concrete pad or on isolated concrete footings at each mounting location. Refer to Figure 13 for unit operating weights. A mounting hole is provided in the base of the unit frame at each mounting location. Provide a means of securely anchoring the unit to the mounting surface. Level the unit carefully. Refer to “Unit Leveling”.

Neoprene Isolators

Install the optional neoprene mounting isolators at each mounting location.

Refer to Figure 13 for isolator selection, placement and loading information.

Isolators are identified by color and by the isolator part number.

Bolt the isolators to the mounting surface. Do not fully tighten the mounting bolts. Mount the unit on the isolators and install a 1/2”nut on each isolator positioning pin. Maximum isolator deflection should be approximately 1/4-inch. Level the unit carefully. Refer to “Unit Leveling”. Now fully tighten isolator mounting bolts.

Unit Leveling Before snugging down the mounting bolts, level the unit carefully. Check unit level end-to-end by placing a level on the top surface of the unit frame. Unit should be level to within 1/4-inch (6.35 mm) over its length. Place the level on the unit frame to check front-to-back level. Adjust to within 1/4” (35 mm) of level front-to-back. Use the adjustable spring isolators or shims to level the unit.

Water Piping Thoroughly flush all water piping to the unit before making the final piping connections to the unit.

CAUTION

Use Piping Strainers!

To prevent evaporator damage, pipe strainers must be installed in the water supplies to protect components from water born debris. Trane is not responsible for equipment-only-damage caused by water born debris.

CAUTION

Proper Water Treatment!

The use of untreated or improperly treated water in a RTAA may result in scaling, erosion, corrosion, algae or slime. It is recommended that the services of a qualified water treatment specialist be engaged to determine what water treatment, if any, is required. Trane assumes no responsibility for equipment failures which result from untreated or improperly treated water, or saline or brackish water.

RTAA-SVX01A-EN 23

Figure 13 Isolator Placement for Typical RTAA Packaged Unit 70 – 125 Tons

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Figure 14 Isolator Placement for RTAA with Remote Evaporator

RTAA-SVX01A-EN 25

Evaporator Water Piping Figure 15 illustrates typical evaporator piping components. Components and layout will vary slightly, depending on the location of connections and the water source.

CAUTION

Evaporator Damage!

The chilled water connections to the evaporator are to be

“victualic” type connections. Do not attempt to weld these connections, as the heat generated from welding can cause internal damage to the evaporator.

The chilled water connections are on the left side of the unit (when facing the control panel). If it is necessary for the chilled water piping to enter the unit from the right side, elbows can be used to route the piping 180° over the top of the evaporator.

A vent is provided on the top of the evaporator at the leaving water end. Be sure to provide additional vents at high points in the piping to bleed air from the chilled water system. Install necessary pressure gauges to monitor the entering and leaving chilled water pressures.

CAUTION

Chilled Water Components Damage!

To prevent damage to chilled water components, do not allow evaporator pressure (maximum working pressure) to exceed

215 psig.

Provide shutoff valves in lines to the gauges to isolate them from the system when they are not in use. Use rubber vibration eliminators to prevent vibration transmission through the water lines.

If desired, install thermometers in the lines to monitor entering and leaving water temperatures. Install a balancing valve in the leaving water line to control water flow balance. Install shutoff valves on both the entering and leaving water lines so that the evaporator can be isolated for service.

A pipe strainer must be installed in the entering water line to prevent water-borne debris from entering the evaporator.

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Evaporator Piping Components “Piping components” include all devices and controls used to provide proper water system operation and unit safety. These components and their general locations are given below.

Entering Chilled Water Piping

• Air vents (to bleed air from system).

• Water pressure gauges with shutoff valves.

• Vibration eliminators.

• Shutoff (isolation) valves.

• Thermometers (if desired).

• Cleanout tees.

• Relief valve.

• Pipe strainer.

Leaving Chilled Water Piping Air vents (to bleed air from system).

• Air vents (to bleed air from system).

• Water pressure gauges with shutoff valves.

• Vibration eliminators. Shutoff (isolation) valves.

• Thermometers.

• Cleanout tees.

• Balancing valve.

• Flow Switch (If desired).

Figure 15 Suggested Piping for Typical RTAA Evaporator

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CAUTION

Evaporator Damage!

To prevent evaporator damage, do not exceed 215 psig (14.6 bar) evaporator water pressure.

Evaporator Drain A 3/4” drain connection is located under the outlet end of the evaporator. This may be connected to a suitable drain to permit evaporator drainage during unit servicing. A shutoff valve must be installed on the drain line.

Chilled Water Flow Switch Chilled water flow protection is provided by the UCM without the need for a chilled water flow switch. A flow switch for chilled water is strictly discre-tionary but if not installed, a signal must be sent to the chiller to indicate that water flow has been established, eg. chilled water pump motor starter auxiliary contacts, building automation system, etc.

If additional chilled water flow protection is desired, use a field-installed flow switch or differential pressure switch with the pump motor starter auxiliary contacts to sense system water flow. Install and wire the flow switch in series with the chilled water pump motor starter auxiliaries (refer to “Interlock Wiring”).

Specific connection and schematic wiring diagrams are shipped with the unit.

Some piping and control schemes, particularly those using a single water pump for both chilled and hot water, must be analyzed to determine how and or if a flow sensing device will provide desired operation.

Follow the manufacturer's recommendations for selection and installation procedures. General guidelines for flow switch installation are outlined below:

1. Mount the switch upright, with a minimum of 5 pipe diameters of straight horizontal run on each side. Do not install close to elbows, orifices or valves.

NOTE: The arrow on the switch must point in the direction of flow.

2. To prevent switch fluttering, remove all air from the water system.

NOTE: The UCM provides a 6-second time delay after a “loss-of flow” diagnostic before shutting the unit down. Contact a qualified service representative if nuisance machine shutdowns persist.

3. Adjust the switch to open when water flow falls below nominal. Evapora-tor data is shown in Figure 16 Refer to Table 1 for minimum flow recom-mendations. Flow switch contacts are closed on proof of water flow.

4. Install a pipe strainer in the entering evaporator water line to protect components from water-borne debr‘is.

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Water Treatment

Using untreated or improperly treated water in these units may result in inefficient operation and possible tube damage. Consult a qualified water treatment specialist to determine whether treatment is needed.

Customer Note

The use of improperly treated or untreated water in this equipment may result in scaling, erosion, corrosion, algae or slime. The services of a qualified water treatment specialist should be engaged to determine what treatment, if any, is advisable. The Trane Company warranty specifically excludes liability for corrosion, erosion or deterioration of Trane equipment. Trane assumes no responsibilities for the results of the use of untreated or improperly treated water, or saline or brackish water.

Water Pressure Gauges

Install field-supplied pressure gauges (with manifolds, whenever practical) as shown in Figure 15. Locate pressure gauges or taps in a straight run of pipe;

avoid placement near elbows, etc. Be sure to install the gauges at the same elevation.

To read manifolded pressure gauges, open one valve and close the other (depending upon the reading desired). This eliminates errors resulting from differently calibrated gauges installed at unmatched elevations.

Figure 16 RTAA Evaporator Water Pressure Drop

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Water Pressure Relief Valves

Install a water pressure relief valve in the evaporator inlet piping between the evaporator and the inlet shutoff valve, as shown in Figure 15. Water vessels with close-coupled shutoff valves have a high potential for hydrostatic pressure buildup on a water temperature increase. Refer to applicable codes for relief valve installation guidelines.

Freeze Protection

If the unit will remain operational at subfreezing ambient temperatures, the chilled water system must be protected from freezing, following the steps listed below:

1. Heat tape is factory-installed on the packaged unit evaporator and will protect it from freezing in ambient temperatures down to -20 F.

2. Install heat tape on all water piping, pumps, and other components that may be damaged if exposed to freezing temperatures. Heat tape must be designed for low ambient temperature applications. Heat tape selection should be based on the lowest expected ambient temperature.

3. Add a non-freezing, low temperature, corrosion inhibiting, heat transfer fluid to the chilled water system. The solution must be strong enough to provide protection against ice formation at the lowest anticipated ambient temperature. Refer to Table 1 for evaporator water storage capacities.

NOTE: Use of glycol type antifreeze reduces the cooling capacity of the unit and must be considered in the design of the system specifications.

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Installation — Remote Evaporator

The RTAA outdoor unit with the remote evaporator option is shipped as two pieces: the outdoor unit (condenser) and the evaporator. Short suction line connections are provided with the outdoor condensing unit. The liquid line connections are at the end opposite the control panel.

The remote evaporator is shipped complete with factory-mounted refrigeration specialties (electronic expansion valves, sight-glasses and removable core filter-dryers). All evaporator refrigerant line connections are at one end of the evaporator. The installing contractor need only provide and install the inter-connecting refrigerant piping between the remote evaporator and the outdoor condensing unit and liquid line isolation valves. In some instances, the installing contractor may also need to lengthen the factory installed suction accumulator.

System Configuration and Interconnecting Refrigerant Piping The system may be configured in any of the four arrangements shown in Figure 17 through Figure 20. The configurations and their associated elevations, along with the total distance between the remote evaporator and the compressor/condenser section, play a critical role in determining suction and liquid line sizes. This will also affect field refrigerant and oil charges.

Consequently, there are physical limits which must not be violated if the system is to operate as designed. Please note the following requirements for field installation:

RTAA-SVX01A-EN 31

Figure 17 Remote Evaporator Installation

No Elevation Difference, Rise of Suction and Liquid Lines not to exceed 20 inches or Less

Figure 18 Remote Evaporator Installation

No Elevation Difference, Rise of Suction and Liquid Lines no to exceed 15 feet or Less

(Suction accumulator may be required)

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Figure 19 Remote Evaporator Installation

Condensing Unit Above Evaporator – 100 Feet or Less

Figure 20 Remote Evaporator Installation

Condensing Unit Below Evaporator – 15 Feet or Less

(Suction accumulator may be required)

RTAA-SVX01A-EN 33

1. The remote evaporator MUST be matched with its respective outdoor condensing unit.

2. The circuit number on the outdoor condensing unit must match the circuit number on the evaporator, i.e. circuit #1 on the outdoor condensing unit must be connected with circuit # 1 on the remote evaporator and likewise for circuit # 2.

See Figure 21 for circuit number identification. RTAA Circuit Capacities are shown in Table 2.

CAUTION

Equipment Damage!

If the circuits are crossed, serious equipment damage may occur.

Figure 21 Refrigerant Circuit Identification

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3. Piping between the evaporator and outdoor unit is not to exceed 200 actual feet and/or an equivalent length of 300 feet. (The latter includes the equivalent length of pressure drops of all associated field installed fittings, valves, accessories, and straight lengths of interconnecting piping including the suction accumulator.)

4. Horizontal portions of suction lines must be downward sloping toward the compressor at least 1/2 inch for each 10 feet of run. This promotes the movement of oil in the direction of gas flow.

5. Suction lines must be insulated.

6. The line sizes defined in Table 4, 5, and 6 are to be used only for 40-50 F leaving water temperature and/or full-load ice-making applications.

NOTE: The factory must size piping for leaving water temperatures other than 40-50 F.

Table 2 RTAA Circuit Capacities (nominal tons)

Model Circuit 1 Circuit 2

70 35 35

80 40 40

90 50 40

100 50 50

110 60 50

125 60 60

Table 3 Equivalent Lengths of Non-Ferrous Valves and Fittings (feet)

Line Size

Inches OD

Globe

Valve

Short Angle

Valve

Short Radius

ELL

Long Radius

ELL

1-1/8 87 29 2.7 1.9

1-3/8 102 33 3.2 2.2

1-5/8 115 34 3.8 2.6

2-1/8 141 39 5.2 3.4

2-5/8 159 44 6.5 4.2

3-1/8 185 53 8 5.1

Reproduced by permission of Air Conditioning and Refrigeration Institute

RTAA-SVX01A-EN 35

Table 4 Liquid Line Sizes

35 Ton Circuit 40 Ton Circuit

Total

Equiv.

Length

(ft.)

Liquid Line Size (OD”) Total

Equiv.

Length

(ft.)

Liquid Line Size (OD”)

Horizontal or

Downflow

Upflow

1-5 ft.

Upflow

6-10 ft.

Upflow

11-15 ft.

Horizontal or

Downflow

Upflow

1-5 ft.

Upflow

6-10 ft.

Upflow

11-15 ft.

25 1.125 1.125 1.125 1.125 25 1.125 1.125 1.125 1.125 50 1.125 1.125 1.125 1.125 50 1.125 1.125 1.125 1.375 75 1.125 1.125 1.125 1.375 75 1.125 1.125 1.125 1.375 100 1.125 1.125 1.125 1.375 100 1.125 1.125 1.125 1.375 125 1.125 1.125 1.125 1.375 125 1.125 1.125 1.375 1.375 150 1.125 1.125 1.125 1.375 150 1.125 1.125 1.375 1.375 175 1.125 1.125 1.375 1.375 175 1.125 1.375 1.375 1.625 200 1.125 1.125 1.375 1.375 200 1.125 1.375 1.375 1.625 225 1.125 1.125 1.375 1.625 225 1.375 1.375 1.375 1.625 250 1.125 1.375 1.375 1.625 250 1.375 1.375 1.375 1.625 275 1.125 1.375 1.375 1.625 275 1.375 1.375 1.375 1.625 300 1.375 1.375 1.375 1.625 300 1.375 1.375 1.375 1.625

50 Ton Circuit 60 Ton Circuit

Total

Equiv.

Length

(ft.)

Liquid Line Size (OD”) Total

Equiv.

Length

(ft.)

Liquid Line Size (OD”)

Horizontal or

Downflow

Upflow

1-5 ft.

Upflow

6-10 ft.

Upflow

11-15 ft.

Horizontal or

Downflow

Upflow

1-5 ft.

Upflow

6-10 ft.

Upflow

11-15 ft.

25 1.125 1.125 1.125 1.125 25 1.125 1.125 1.125 1.375 50 1.125 1.125 1.125 1.375 50 1.125 1.125 1.375 1.375 75 1.125 1.125 1.375 1.375 75 1.125 1.125 1.375 1.625 100 1.125 1.125 1.375 1.375 100 1.125 1.375 1.375 1.625 125 1.125 1.375 1.375 1.625 125 1.375 1.375 1.375 1.625 150 1.125 1.375 1.375 1.625 150 1.375 1.375 1.375 1.625 175 1.375 1.375 1.375 1.625 175 1.375 1.375 1.625 1.625 200 1.375 1.375 1.375 1.625 200 1.375 1.375 1.625 2.125 225 1.375 1.375 1.625 1.625 225 1.375 1.375 1.625 2.125 250 1.375 1.375 1.625 2.125 250 1.375 1.625 1.625 2.125 275 1.375 1.375 1.625 2.125 275 1.375 1.625 1.625 2.125 300 1.375 1.375 1.625 2.125 300 1.375 1.625 1.625 2.125

Table 5 Suction Line Sizes (“O.D.”) for Upflow Lines

Circuit Size

(nominal tons)

Outside Diameter

(inches)

35 2-1/8

40 2-1/8

50 2-5/8

60 2-5/8

36 RTAA-SVX01A-EN

7. Figure 17 depicts an installation where the remote evaporator elevation is the same as that of the outdoor condensing unit. The suction and liquid line are horizontal or down flowing only.

8. Figure 18 shows a variation to Figure 17. The remote evaporator and out-door condensing unit are at the same elevation but interconnecting piping may be installed up to 15 feet above the base elevation. In this case a suction line trap is required to assure oil return, and the suction accumu-lator line must be extended at least by the amount determined from Table 7.

9. For installations where the remote evaporator is at a lower elevation than the outdoor condensing unit as shown in Table 4, the elevation difference is not to exceed 100 feet. An inverted liquid line trap to prevent unwanted free cooling modes and a suction line trap to assure oil return from the evaporator must be included on both circuits as shown. The apex of the liquid line trap should be at a height above the condenser coils. The high-est point of the suction line piping must not exceed 4 inches above the outdoor condensing unit suction line connection point.

10. When the elevation of the remote evaporator exceeds that of the outdoor condensing unit as shown in Figure 20, the elevation difference may not exceed 15 feet. The suction accumulator line must be extended at least by the amount determined from Table 7. This line must not exceed 4 inches above the outdoor unit suction line connection point. An inverted suction line trap whose apex is 3 to 15 feet above the elevation of the remote evaporator is required in both circuits.

11. Compressor and oil separator heaters must be on at least 24 hours prior to compressor start.

Table 6 Suction Line Sizes (“O.D.”) for

Horizontal and/or Downflow Lines

Circuit Size:

Total Equiv.

Length (ft.) 35 Ton 40 Ton 50 Ton 60 Ton

25 2.125 2.125 2.625 2.625 50 2.125 2.125 2.625 2.625 75 2.125 2.125 2.625 2.625 100 2.125 2.625 2.625 2.625 125 2.125 2.625 2.625 2.625 150 2.625 2.625 2.625 2.625 175 2.625 2.625 2.625 3.125 200 2.625 2.625 2.625 3.125 225 2.625 2.625 2.625 3.125 250 2.625 2.625 2.625 3.125 275 2.625 2.625 3.125 3.125 300 2.625 2.625 3.125 3.125

RTAA-SVX01A-EN 37

Line Sizing To determine the appropriate outside diameter for field installed liquid and suction lines, it is first necessary to establish the equivalent length of pipe for each line. It is also necessary to know the capacity (tons) of each circuit.

Circuit capacities for each RTAA unit are listed in Table 2.

Liquid Line Sizing Steps

Line sizing is an iterative process. While iterating to determine the proper equivalent line length use the “Horizontal or Downflow” column of Table 4.

After the final equivalent line length has been determined in step # 9, then break down the piping into it's “Horizontal or Downflow” and “Upflow” components and select the proper outside diameter. Note that “Upflow” has a column for one to five, six to ten, and eleven to fifteen feet.

The steps to compute liquid line size are as follows:

1. Compute the actual length of field installed piping.

2. Multiply the length from step # 1 by 1.5 to estimate the equivalent length.

3. Using Table 4 for the proper tonnage circuit, look in the “Horizontal or Downflow” column. Find the outside diameter that corresponds to the equivalent length computed in step # 2.

4. With the outside diameter found in step # 3, use Table 3 to determine the equivalent lengths of each fitting in the field installed piping.

5. Sum the equivalent lengths of all the field installed elbows.

6. Add the length found in step # 5 to the actual length from step # 1. This is your new equivalent line length.

7. Using Table 4 again, find the new outside diameter that corresponds to the new equivalent line length from step # 6.

8. Using Table 2b and the new outside diameter found in step # 7, find the equivalent line length of each elbow, and sum them.

9. Add the length found in step # 8 to the actual length from step # 1. This is your final equivalent line length.

10. With the final equivalent line length found in step # 9, use Table 4 to select the proper outside diameter for horizontal or downflow lines, and any upflow lines.

38 RTAA-SVX01A-EN

Example Liquid Line Sizing For this example, refer to Table 2, 3, 4, and Figure 22, and assume a 50 ton circuit.

1. From Figure 22, the actual length of field installed piping is:

80+8+8+21 =117 feet

2. Estimate equivalent line length:

117 feet x 5=175 feet

3. From Table 4 for a 50 ton circuit, for 175 equivalent feet the OD is 1-3/8 inches.

4. In Figure 22 there are six long-radius elbows. From Table 3, for 1-3/8 inch elbows, the equivalent feet is:

6 elbows x 2.2 feet = 13.2 feet

5. Adding equivalent feet from step #4 to step #1 gives:

13.2 feet + 117 feet = 130.2 feet

6. From Table 4, for a 50 ton circuit, for 125 equivalent feet (nearest to 130.2), the OD is 1-1/8 inches

7. From Table 3, for 1-1/8" OD long-radius elbows, the equivalent feet is:

6 elbows x 1.9 feet = 11.4 feet

8. Adding equivalent feet from step #7 to step #1 gives:

11.4 feet + 117 feet = 128.4 feet

Table 7 Additional Suction Accumulator Line

Required Length in Feet of Field Installed Suction Line Accumulator

Liquid Line

Length in

Actual Ft.

35 Ton Circuit 40 Ton Circuit 50 Ton Circuit 60 Ton Circuit

2 1/8" O.D.

Suction

Line

2 5/8" O.D.

Suction

Line

2 1/8" O.D.

Suction

Line

2 5/8" O.D.

Suction

Line

2 5/8" O.D.

Suction

Line

3 1/8" O.D.

Suction

Line

2 5/8" O.D.

Suction

Line

31/8"O.D.

Suction

Line

20 1 1 5 3 9 6 14 10

40 7 5 14 9 15 11 21 15

60 14 9 23 15 21 15 27 19

80 20 13 32 21 28 19 33 23

100 26 17 N/A 26 34 24 40 28

120 32 21 N/A 32 40 28 46 32

140 N/A 25 N/A 38 46 33 52 37

160 N/A 29 N/A 43 53 37 N/A 41

180 N/A 33 N/A 49 59 41 N/A 45

200 N/A 37 N/A 55 65 46 N/A 50

RTAA-SVX01A-EN 39

9. From Table 4, for a 50 ton circuit, for 125 equivalent feet (also nearest to

128.2 feet), the OD is still:

Horizontal or Downflow = 1 1/8 inches

10. From 22, there is 8 feet of up-flow on the liquid line inverted trap. There-fore, select:

Upflow = 1-3/8 inches

Suction Line Sizing Steps The steps to compute suction line size are as follows:

1. Break the suction line into it's “Upflow” and “Horizontal or Downflow” components. The horizontal or downflow length should include that portion of field-installed suction line within the condensing unit's base.

See Figure 22.

2. From Table 5, select the appropriate “Upflow” suction line outside diame-ter according to the circuit tonnage. This is the diameter of the upflow suction line and any fittings in the upflow line.

3. With the diameter found in step #2, use Table 3 to find the equivalent length of each fitting in the upflow line. Sum the equivalent lengths of all the fittings in the upflow line.

4. Sum the final length found in step #3 with the actual length of the upflow line. This is the final equivalent length of the upflow portion of the suction line.

5. Multiply by 1.5, the actual length of the horizontal or downflow portion of the suction line.

6. Add the length from step #5 to the length from step # 4. This is the first estimate of the equivalent line length.

7. In Table 6 find the column for the circuit tonnage you are sizing. In that

Figure 22 Liquid Line Sizing Example

40 RTAA-SVX01A-EN

column find the outside diameter that corresponds to the equivalent length computed in step #6.

8. Use Table 3 and the diameter found in step #7 to determine the equiva-lent lengths of each fitting.

9. Sum the following: equivalent lengths of the fittings from step #8, the actual length of the horizontal or downflow suction line, and the equiva-lent length of the upflow line found in step # 4. This is the new estimate of the equivalent length of the entire suction line.

10. With the new length found in step #9, go back to Table 6 and find the new diameter for the circuit you are sizing.

11. Repeat steps #8-10 with the new diameter found in step # 10.

12. The diameter found in step #11 is the horizontal or downflow suction line diameter.

13. The diameter found in step #2 is the diameter of the upflow suction line and any fittings in the upflow line.

NOTE: The diameters of the upflow, and horizontal or downflow portions of the suction line may differ depending on the application.

Example Suction Line Sizing

For this example, refer to Table 3, 5, 6, and 23, and assume a 50 ton circuit on a 100 ton chiller.

1. From 23, the actual length of upflow, and horizontal or downflow is:

upflow (20 + 5) = 25 feet horizontal or downflow (75+8) = 83 ft.

2. Table 5 for a 50 ton circuit shows: Upflow suction line outside diameter

= 2-5/8 inches

3. According to Figure 23, there are 6 long radius ELLs. From Table 2b for a diameter of 2-5/8 inches:

6 elbows x 3.4 feet = 20.4 feet

4. Final equivalent length of upflow suction line:

20.4 + 25 = 45.4 feet

5. There are no fittings in the horizontal portion. Therefore, the final equivalent line length is:

45.4 + 83 = 128.4 feet

6. From Table 6, for a 50 ton circuit, and 125 equivalent feet

(nearest to 128.4):

Horizontal or downflow suction line diameter = 2-5/8 inches

NOTE: In this example, the horizontal line is pitched downward in the direction of flow.

RTAA-SVX01A-EN 41

Suction Accumulator Sizing

Installations similar to those in Figure 18 and 20 will require that the suction accumulator be extended at least by the amount shown in 7. The suction accumulator length in feet is dependent upon: circuit tonnage, suction line O.D., and actual liquid line length.

The following example uses Figure 23 and assumes a 50 ton circuit with a 2-5/8 inch O.D. suction line. Figure 23 illustrates an installation where the remote evaporator is 11 feet above the outdoor condensing unit. A liquid line at the same elevation as the evaporator runs horizontally 25 feet. Then it drops 11 feet to the same elevation as the suction line connecting points on the outdoor condensing unit, and runs horizontally 5 feet to the outdoor condensing unit. From Figure 23, the actual length of liquid line is 41 feet (25 + 11+5). With the previously mentioned assumptions, Table 7 indicates 15 feet of 2-5/8 inch O.D. suction accumulator needs to be added. Figure 24 shows one method of piping the additional 15 feet.

NOTE: In this example, if the liquid and suction lines had dropped the 11 feet from the evaporator and then run the 25 feet horizontal at the outdoor condensing unit's elevation, the 15 feet of suction accumulator would not be required.

NOTE: When sizing suction line diameters, the length of the suction accumulator should be included in any computations.

The height of the suction accumulator, specified in Table 7, may not exceed 4 inches above the suction line connecting point at the outdoor condensing unit. In addition, the suction accumulator must be pitched toward the compressor 1/2 inch per 10 feet of horizontal run.

42 RTAA-SVX01A-EN

Figure 23 Suction Accumulator Sizing Example

RTAA-SVX01A-EN 43

Piping Installation Procedures The outdoor unit and the evaporator are shipped with a 25 psig holding pressure of dry nitrogen. Do not relieve this pressure until field installation of the refrigerant piping is to be accomplished. This will require the removal of the temporary pipe caps.

NOTE: Use Type L refrigerant-grade copper tubing only.

The refrigerant lines must be isolated to prevent line vibration from being transferred to the building. Do not secure the lines rigidly to the building at any point.

All horizontal suction lines should be pitched downward, in the direction of flow, at a slope of 1/2 in. per 10 feet of run. This allows for larger line size, which will improve unit efficiency.

Important: Relieve nitrogen pressure before removing end caps.

Do not use a saw to remove end caps, as this may allow copper chips to contaminate the system. Use a tubing cutter or heat to remove the end caps.

� WARNING

Prevent Injury!

When sweating line connections, always provide a sufficient purge of dry nitrogen through the tubing to prevent the formation of oxides/scaling cause by high temperature from brazing. Use a pressure regulator in the line between the unit and the high pressure nitrogen cylinder to avoid over pressurization and possible explosion. If any refrigerant or refrigerant vapors are present a thorough purge with dry nitrogen will prevent the possible formation of toxic phosgene gas. Failure to follow these recommendations could result in death or serious injury.

Refrigerant Sensors The suction line refrigerant sensors must be installed by the contractor installing the refrigerant piping. The sensors are prewired and each is “wire-tied” to its respective liquid line. Fittings and adapters for mounting of the sensors are located in the remote evaporator terminal box. See Figure 24 for mounting instructions.

44 RTAA-SVX01A-EN

Figure 24 Refrigerant Sensor Mounting and Wiring

RTAA-SVX01A-EN 45

Leak Test and Evacuation After installation of the refrigerant piping, thoroughly test the system for leaks. Pressure test the system at pressures required by local codes.

Immediately before evacuation, install the liquid line filter cores. These will be shipped with the evaporator.

NOTE: Do not install these before the circuit is ready for evacuation, as the cores will absorb moisture from the atmosphere.

For field evacuation, use a rotary-type vacuum pump capable of pulling a vacuum of 100 microns or less. Follow the pump manufacturer's instructions for proper use of the pump. The line used to connect the pump to the system should be copper and be the largest diameter that can be practically used. A larger line size with minimum flow resistance can significantly reduce evacuation time.

Use the ports on the compressor suction service valves and the liquid line shutoff valves for access to the system for evacuation. Insure that the compressor suction service valve, the liquid line shutoff valve, the oil line shutoff valve and any field installed valves are open in the proper position before evacuating.

Insulate the entire suction line and the suction accumulator line. Where the line is exposed to the weather, wrap it with weatherproof tape and seal with weather-proof compound.

Refrigerant and Additional Oil Charge

Refrigerant Charge Determination

The approximate amount of refrigerant charge required by the system must be determined by referring to Table 8 and must be verified by running the system and checking the liquid line sightglasses.

To determine the…