Emerson Copeland Scroll Compressors for CO2 Subcritical Refrigeration R-744 User Manual

Emerson Copeland Scroll compressors are designed for CO2 subcritical refrigeration systems, offering efficiency, reliability, and liquid handling advantages. Ideal for low-temperature cascade systems, these compressors can handle high-pressure levels and provide proper lubrication. With a range of models available, they cater to various refrigeration applications.

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AE4-1372 R5 August 2019

Copeland Scroll™ Compressors for CO

Subcritical Refrigeration (R-744)

TABLE OF CONTENTS

Safety Instructions ....................................................... 2

Safety Icon Explanation ........................................... 2

Instructions Pertaining to Risk of Electrical Shock,

Fire, or Injury to Persons .......................................... 3

Safety Statements .................................................... 3

INTRODUCTION ......................................................... 4

FOR LOW TEMPERATURE APPLICATIONS

SUB-CRITICAL DX SYSTEM ...................................... 4

Nomenclature ........................................................... 4

Approved Oils & Refrigerants .................................. 4

Mounting Parts ......................................................... 4

Safety Relief Valves ................................................. 5

High-Pressure Safety Controls ................................ 5

Active Oil Management ............................................ 5

Accumulators ........................................................... 6

Screens .................................................................... 6

Mufflers .................................................................... 6

Electrical Connection ............................................... 7

Crankcase Heaters .................................................. 7

Motor Protection ....................................................... 7

Operating Envelope .................................................. 7

Charging Procedure ................................................. 7

Deep Vacuum Operation .......................................... 7

Shell Temperature .................................................... 8

Pump Down Cycle and Parallel Rack Application .... 8

Low Pressure Safety Control .................................... 8

Minimum Run Time .................................................. 8

ASSEMBLY LINE PROCEDURES ............................... 8

Installing the Compressor ......................................... 8

Assembly Line Brazing Procedure ........................... 8

New Installations ...................................................... 8

‘Hipot’ (AC High Potential) Testing ........................... 9

MAINTENANCE AND REPAIR .................................... 9

Service Procedures .................................................. 9

Compressor Replacement After a Motor Burn ....... 10

General Guidelines and More Information ............. 10

FIGURES

Figure 1 CO

Low Temp. Subcritical DX System ...... 12

Figure 2 Specially designed rubber rommets Kit # 527-

0157-00 ...................................................................... 13

Figure 3 Oil Management Control OMC-CO2 ............ 13

Figure 5 Three Phase Power Circuit .......................... 15

Figure 6 - ZO Compressor Operating Envelope ........ 15

Figure 7 Compressor Electrical Connection ............... 15

Figure 4 Suction Side Pressure Relief Valve

Requirements ............................................................. 14

Revision Tracking R4

Pg. 2 New Pressure Safety Icon added

Pg. 4 Caution tag added to superheat requirement.

Pg. 4 Notes about oil recharging values added.

Pg. 5 Model numbers chart moved to pag. 10 and

ZOD34K3E and ZOD104KCE added.

Pg. 5 Regulatory Compliance reference updated.

Pg. 5 ZO104KCE data updated.

Pg. 5 High-pressure relief valve settings changed.

Pg. 6 Modified low pressure cut.

Pg. 7 Charging Procedures changed

Pg. 9 Maintenance and Repair section added

Revision Tracking R5

Pg.6 Added CO2 OMB Oil Management Links

Pg. 10 Table of AE-Bulletins and documentation related with this Bulletin.

Pg. 10 Nomenclature details added.

Pg. 10 Oil and Refrigerant table added

Pg. 10 Crankcase kit table added

Pg. 11 OMC CO2 Specification Chart added

Pg. 11 Drawing of Subcritical DX System changed.

Pg. 11 and Pg. 12 Mounting parts drawings added.

Pg. 11 Oil Management drawing added

Pg. 13 Pressure Relief Valve drawing changed.

Pg. 14 Operating Envelop changed.

AE4-1372 R5

Safety Instructions

Copeland Scroll™ compressors are manufactured according to the latest U.S. and European Safety

Standards. Particular emphasis has been placed on the user's safety. Safety icons are explained below and safety instructions applicable to the products in this bulletin are grouped on Page 3. These instructions should be retained throughout the lifetime of the compressor. You are strongly advised to follow these safety instructions.

Safety Icon Explanation

DANGER

WARNING

CAUTION

NOTICE

CAUTION

DANGER indicates a hazardous situation which, if not avoided, will result in death or serious injury.

WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.

CAUTION, used with the safety alert symbol, indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.

NOTICE is used to address practices not related to personal injury.

CAUTION, without the safety alert symbol, is used to address practices not related to personal injury.

FLAMMABLE

PRESSURE indicates a dangerous proximity to high pressure section of the system.

AE4-1372 R5

Instructions Pertaining to Risk of Electrical Shock, Fire, or Injury to Persons

WARNING

ELECTRICAL SHOCK HAZARD

• Disconnect and lock out power before servicing.

• Discharge all capacitors before servicing.

•

Use compressor with grounded system only.

•

Molded electrical plug must be used when required.

•

Refer to original equipment wiring diagrams.

•

Electrical connections must be made by qualified electrical personnel.

•

Failure to follow these warnings could result in serious personal injury.

WARNING

PRESSURIZED SYSTEM HAZARD

• System contains refrigerant and oil under pressure.

• Remove refrigerant from both the high and low compressor side before removing compressor.

• Never install a system and leave it unattended when it has no charge, a holding charge, or with the service valves closed without electrically locking out the system.

•

Use only approved refrigerants and refrigeration oils.

•

Personal safety equipment must be used.

•

Failure to follow these warnings could result in serious personal injury.

WARNING

BURN HAZARD

• Do not touch the compressor until it has cooled down.

• Ensure that materials and wiring do not touch high temperature areas of the compressor.

• Use caution when brazing system components.

• Personal safety equipment must be used.

• Failure to follow these warnings could result in serious personal injury or property damage.

CAUTION

COMPRESSOR HANDLING

•

Use the appropriate lifting devices to move compressors.

•

Personal safety equipment must be used.

•

Failure to follow these warnings could result in personal injury or property damage.

Safety Statements

• Refrigerant compressors must be employed only for their intended use.

• Only qualified and authorized HVAC or refrigeration personnel are permitted to install commission and maintain this equipment.

•

Electrical connections must be made by qualified electrical personnel.

All valid standards and codes for installing, servicing, and maintaining electrical and refrigeration equipment must be observed.

AE4-1372 R5

INTRODUCTION

This bulletin describes the operating characteristics, design features, and application requirements for all

Copeland Scroll

™

compressors for refrigeration applications using CO

(R-744) for a subcritical operation. For additional information, please refer to the online product information accessible from the Emeson website at Emerson.com/OPI .

Increasing environmental concerns about the potential direct emissions from HFC-based refrigeration systems into the atmosphere have led system designers to revisit refrigerant R-744 (CO

). In comparison with HFC refrigerants, the specific properties of CO

require changes in the design of the refrigeration system. The ZO range of Copeland

Scroll compressors has been designed to exploit the characteristics of CO

refrigeration systems. The efficiency, reliability and liquid handling advantages of Copeland Scroll technology make it ideal for these applications.

The comparably high pressure level and thermodynamic properties of the refrigerant CO

have driven system designers towards low temperature cascade systems, where CO

is used as a direct expanding refrigerant in the low temperature stage. In these subcritical cascade applications, the CO

2 compressor in the low temperature stage is still exposed to pressure levels higher than in standard HFC-based systems. However, they are limited to pressure levels similar to those already known from air-conditioning applications with refrigerant R-410A. An HFC refrigerant is typically used in the medium temperature stage of the cascade system.

The challenges for CO

compressors compared to HFC compressors lie in the high pressure levels, the higher mass flow for a given displacement, and designing for proper lubrication. In terms of mechanical strength, ZO scroll compressors benefit from many years of experience with R-410A air-conditioning compressors, which operate at similar pressure levels as CO

2 compressors.

FOR LOW TEMPERATURE APPLICATIONS

SUB-CRITICAL DX SYSTEM

Figure 1

at the end of this bulletin shows a cascade system diagram with HFC refrigerant for the high side and sub-critical CO

for the low stage refrigerant.

Nomenclature

The model designation contains the following technical information about the compressor:

ZO D 34 K 3 E - TFD - 269

Z = Compressor family: Scroll

O = Refrigerant: R744, subcritical operation

D = Digital Model; Blank= Standard Model

34K = Nominal Capacity (kBTU/hr)

3 = Model variation

E = Oil type: POE oil

TFD = Electrical Description:

T = Three Phases

F = Internal Inherent Motor Protection

5,7,D,E = Nominal Voltage Range

269 = Bill of material

Please refer to Online Product Information at

Emerson.com/OPI for details.

Refer to Table 1 for a detailed list of ZO Family Models.

Approved Oils & Refrigerants

Recommended quality for carbon dioxide purity grade is 4.0 [(≥ 99.99 %) H2O≤10ppm, O2≤10ppm,

N2≤50ppm] or higher.

Emkarate RL 68 HB is approved for new and service applications.

Oil recharge values can be taken from

Copeland Scroll™ compressors brochures or

Copeland ® brand Products Selection Software.

CAUTION

The compressor superheat at suction should be controlled such that it is always above 36°F (20K) to avoid oil dilution in the compressor but low return gas temperature enough to keep the compressor discharge temperature below 250°F (121.1°C), especially at high compressor ratios (high condensing and low evaporating temperatures).

Note:

A separate heat-exchanger may be required to maintain the recommended superheat.

Refer to

Table 2 for reference.

Mounting Parts

Specially designed rubber grommets are available for mounting (Kit 527-0157-00). These grommets are formulated from a high durometer material specifically designed for refrigeration applications. The high durometer limits the compressors motion thereby minimizing potential problems of excessive tubing stress. Sufficient isolation is provided to prevent

AE4-1372 R5 vibration from being transmitted to the mounting structure. The use of standard soft grommets is not recommended .

Refer Figure 2 for details.

Safety Relief Valves

CAUTION

In a closed system filled with CO

the pressure can rise above 725 psig (50 Bar) under some ambient conditions. The system must be equipped with safety relief valves to ensure that the compressor’s low side and high side pressures are not exceeded (see below).

If the unit is shut down for service or other reasons, the pressure will rise due to ambient heat. To prevent the loss of charge at shut down through the relief valves, it is recommended to provide additional cooling to keep the pressure below the maximum standstill pressure of the suction side. This can be achieved using a small auxiliary condensing unit connected to an uninterruptable power supply, that removes heat from the R744 liquid receiver. The auxiliary condensing unit will not be sufficient to maintain the low-stage system below the Maximum Allowable Operation Pressure if there is a load from the evaporators.

Refer to ANSI/ASHRAE Standard 15-2016, Section

9.7.5 and ANSI/ASHRAE 15 appendix C-2016,.

ZO Maximum Operating pressures

Suction side

Discharge side

500 psig (34.5 Bar)

625 psig (43.1 Bar)

The requirements for Copeland Scroll compressors with

per Underwriters Laboratory (UL) state that a system with a CO

compressor must be installed with an approved suction pressure relief valve. ASME highpressure relief valves are the only valves currently approved for use with the Copeland Scroll CO

models.

The installation of the above valve must meet the following criteria:

1. There must be an open flow path from the compressor suction sump to the relief valve. This is accomplished by connecting the relief valve to the correct port on the suction Rotalock valve.

This port is open to the compressor sump no matter what position the valve stem is located.

The relief valve itself can be remotely located as long as the path from compressor suction sump and the valve is always open.

2. This flow path cannot be shut off in any way by a valve.

Figure 4 represents the correct (a) and incorrect (b) way

to apply the pressure relief valve. Failure to apply the high-pressure relief valve correctly will void any UL approval of the system.

The high-pressure relief valve should be located such that the path between the valve and the low side of the compressor is always open and cannot be shut off in any way by a valve. Note that the valve opens only once and must be replaced if it opens.

A 500 psig (34.5 Bar) high-pressure relief valve kit is shipped with the compressor. Contact Application

Engineering for alternative pressure relief valves.

ZO compressors have Rotalock valve fittings. Rotalock shut-off valves are available for the suction as well as discharge side. Using either straight or angled adaptors provides a way to convert a Rotalock into a brazing connection.

Tightening Torques

Torque Lbs

Rotalock 1"-1 UNF 60-70 ft.lb.

Rotalock 1"1/4-12 UNF

High-Pressure Safety Controls

75-85 ft.lb

A CO

approved ASME safety pressure relief valve(s) with a setting of 500 psig (34.5 Bar) is required to be pre-installed for standstill conditions.

All sections that can be isolated in the system must have relief valves pre-installed by the system manufacturer with a 500 psig (34.5 Bar) setting.

These high-pressure cut-outs should have a manual reset feature.

Additional Requirements:

Low Pressure Cut-Out on Suction Side:

80 psig (5.5 bar)

High Pressure Cut-Out on Discharge Side: 625 psig

(43.1 Bar)

Discharge Temperature Protection

External discharge line thermostat 998-7022-02

Active Oil Management

An OMC CO2 electronic oil level management system should be used that is suitable for both high and low

pressure oil management systems. The differential pressure required for sufficient oil flow from the oil reservoir to the compressor crankcase depends upon the system. However, 20 psig (1.4 Bar) can be used as

a minimum pressure differential value. Refer to Figure

and Table 4

For more details about OMB-CO2 Oil Management

Devices scan the QR codes below or follow the links available.

- Emerson OMC Video

-

AE4-1372 R5

OMB Adapter Instruction Sheet

https://climate.emerson.com/documents/ombadapter-instructions-en-4924792.pdf

- Emerson OMC Specification Sheet https://climate.emerson.com/documents/omcspecification-sheet-en-us-3584550.pdf

- OMB/C Instructions https://climate.emerson.com/documents/ombc--pa-00388-en-4858298.pdf

Accumulators

Irrespective of system charge, oil dilution may occur if large amounts of liquid refrigerant repeatedly flood back to the compressor during normal running cycles, defrost, and varying loads.

If adequate Compressor Superheat cannot consistently be maintained at minimum of 36°F (20K) an accumulator may be required, as well as the addition of liquid to suction heat exchanger or other means as assuring 36°F (20K) Superheat.

Screens

The use of screens finer than 30 x 30 mesh (0.6 mm openings) anywhere in the system should be avoided with these compressors. Field experience has shown that finer mesh screens used to protect expansion valves, capillary tubes, or accumulators can become temporarily or permanently plugged with normal system debris and block the flow of either oil or refrigerant to the compressor. Such blockage can result in compressor failure.

Mufflers

External mufflers, normally applied to piston compressors in the past, may not be required for

Copeland Scroll compressors.

Individual system tests should be performed to verify acceptability of sound performance. If adequate attenuation is not achieved, use a muffler with a larger cross-sectional area to inlet area ratio. A ratio of 20:1 to

30:1 is recommended.

A hollow shell muffler will work quite well. Locate the muffler 6-18 inches from the compressor for the most effective operation. The farther the muffler is placed from the compressor within these ranges, the more effective. Choose a muffler with a length of 2-6 inches.

AE4-1372 R5

Electrical Connection

The compressor terminal box has a wiring diagram on the inside of its cover. Before connecting the compressor, ensure the supply voltage, the phases and the frequency match the nameplate data. Refer to

Figure 5 for details.

The terminal box is IP21 for all models from ZO21K* to

ZO104K*. The ZO Scroll compressors have threephase induction motors connected in star. Copeland

Scroll compressors, like several other types of compressors, will only compress in one rotational direction. Three phase compressors will rotate in either direction depending upon phasing of the power. Since there is a 50% chance of connecting power in such a way as to cause rotation in the reverse direction, it is important to include notices and instructions in appropriate locations on the equipment to ensure that proper rotation direction is achieved when the system is installed and operated. Verification of proper rotation direction is made by observing that suction pressure drops and discharge pressure rises when the compressor is energized. Reverse rotation will result in no pressure differential as compared to normal values.

A compressor running in reverse will sometimes make an abnormal sound. There is no negative impact on durability caused by operating three phase Copeland

Scroll compressors in the reversed direction for a short period of time (under one hour). After several minutes of reverse operation, the compressor’s internal overload protector will trip shutting off the compressor. If allowed to repeatedly restart and run in reverse without correcting the situation, the compressor bearings will be permanently damaged because of oil loss to the system.

All three phase scroll compressors are wired identically internally. As a result, once the correct phasing is determined for a specific system or installation, connecting properly phased power leads to the identified compressor electrical (Fusite™) terminals will maintain the proper

rotational direction (see Figure 7 ). All three phase scrolls

will continue to run in reverse until the internal overload protector opens or the phasing is corrected.

Crankcase Heaters

A crankase heater is always required. The crankcase heater ust be turned on a minimum of 12 hours prior to starting the compressor and must remain energized during the compressor off cycle.

See Table 3 for reference.

Motor Protection

For the ZO range of compressors, conventional inherent internal line break motor protection is provided.

Operating Envelope

Figure 6 at the end of this bulletin shows the CO

2 cascade operating envelope in relation to R-410A and R-

404A.

Charging Procedure

Do not operate compressor without enough system charge to maintain at least 87 psig (6 Bar) suction pressure.

Do not operate with a restricted suction.

Do not operate with the low-pressure cut-out bridged.

Vapor initial charge should be 145 PSIG (10 Bar). Do not allow a pressure under 87 psig (6 Bar), otherwise it might cause CO

solidification and blocked valves or pipes and consequently, the scrolls may overheat and cause early drive bearing damage.

Do not use the compressor to test the opening set point of the high-pressure cut-out. Bearings are susceptible to damage before they have had several hours of normal running in. Ensure charging equipment is approved for at least 1300 psig (89.6 Bar).

The system should be charged through the liquidreceiver shut-off valve or through a valve in the liquid line. The use of a filter drier in the charging line is highly recommended.

Because there may be several valves in the system it is recommended to charge on both the high and low sides simultaneously to ensure a positive refrigerant pressure is present in the compressor before it runs. The majority of the charge should be placed in the high side of the system to prevent bearing washout during first-time start.

Deep Vacuum Operation

Copeland Scroll compressors should never be used to evacuate a refrigeration or air-conditioning system. The scroll compressor can be used to pump down refrigerant in a unit as long as the pressures remain within the operating envelope. Low suction pressures will result in

AE4-1372 R5 overheating of the scrolls and permanent damage to the compressor drive bearing. ZO scrolls incorporate internal low vacuum protection, the floating seal unloads when the pressure ratio exceeds approximately 10:1.

Shell Temperature

The top shell and discharge line can briefly but repeatedly reach temperatures above 350°F (176.7 °C) if the compressor cycles on its internal protection devices. This only happens under rare circumstances and can be caused by the failure of system components such as the condenser or evaporator fan or loss of charge and depends upon the type of expansion control.

Care must be taken to ensure that wiring or other materials that could be damaged by these temperatures do not come in contact with the shell.

Pump Down Cycle and Parallel Rack Application

A pump down cycle for control of refrigerant migration may be used in conjunction with a crankcase heater when the compressor is located so that cold air blowing over the compressor makes the crankcase heater ineffective.

If a pump down cycle is used on a parallel rack system, a separate external check valve must be added. The scroll discharge check valve is designed to stop extended reverse rotation and prevent high-pressure gas from leaking rapidly into the low side after shut off.

The check valve will in some cases leak more than reciprocating compressor discharge reeds, normally used with pump down, causing the scroll compressor to recycle more frequently. Repeated short-cycling of this nature can result in a low oil situation and consequent damage to the compressor. The low-pressure control differential has to be reviewed since a relatively large volume of gas will re-expand from the high side of the compressor into the low side on shutdown.

Low Pressure Safety Control

Never set the low-pressure control to shut off outside of the operating envelope. To prevent the compressor from running into problems during such faults as loss of charge or partial blockage, the control should not be set lower than -60°F (-51.1°C) equivalent suction pressure

(80 PSIG, 5.51 bar) below the lowest design operating point.

Minimum Run Time

Emerson recommends a maximum of 10 starts per hour.

There is no minimum off time because scroll compressors start unloaded, even if the system has

8 unbalanced pressures. The most critical consideration is the minimum run time required to return oil to the compressor after start-up. To establish the minimum run time, obtain a sample compressor equipped with a sight tube (available from Emerson Climate Technologies) and install it in a system with the longest connecting lines that are approved for the system. The minimum on time becomes the time required for oil lost during compressor start-up to return to the compressor sump and restore a minimal oil level that will ensure oil pickup through the crankshaft. Cycling the compressor for a shorter period than this, for instance to maintain very tight temperature control, will result in progressive loss of oil and damage to the compressor.

ASSEMBLY LINE PROCEDURES

Installing the Compressor

Copeland Scroll compressors leave the factory dehydrated and with a positive dry air charge. Plugs should not be removed from the compressor until the compressor has had sufficient time to warm up if stored outside and is ready for assembly in the unit. The suggested warm up time is one hour per 4°F (2K) difference between outdoor and indoor temperature. It is suggested that the larger suction plug be removed first to relieve the internal pressure. Removing the smaller discharge plug could result in a spray of oil out of this fitting since some oil accumulates in the head of the compressor after Emerson’s run test. The inside of both fittings should be wiped with a lint free cloth to remove residual oil prior to brazing. A compressor containing POE oil should never be left open longer than

5 minutes.

Assembly Line Brazing Procedure

Following are the proper procedures for brazing the suction and discharge lines to a scroll compressor. It is important to flow nitrogen through the system while brazing all joints during the system assembly process.

Nitrogen displaces the air and prevents the formation of copper oxides in the system. If allowed to form, the copper oxide flakes can later be swept through the system and block screens such as those protecting capillary tubes, thermal expansion valves, and accumulator oil return holes. Any blockage of oil or refrigerant may damage the compressor resulting in failure.

New Installations

• The copper-coated steel suction tube on scroll compressors can be brazed in approximately the same manner as any copper tube.

AE4-1372 R5

•

Recommended brazing materials: Any SIL-FOS® material is recommended, preferably with a minimum of 5% silver. However, 0% silver is acceptable.

• Be sure suction tube fitting I.D. and suction tube

O.D. are clean prior to assembly. If oil film is present wipe with denatured alcohol, Dichloro-

Trifluoroethane or other suitable solvent.

• Using a double-tipped torch apply heat in Area 1.

As tube approaches brazing temperature, move torch flame to Area 2. should be operated for a brief period of time to redistribute the refrigerant to a more normal configuration and the system hipot tested again. See

AE4-1294 for megaohm testing recommendations.

Under no circumstances should the hipot test be performed while the compressor is under a vacuum.

MAINTENANCE AND REPAIR

Service Procedures

Scroll Suction Tube Brazing

• Heat Area 2 until braze temperature is attained, moving torch up and down and rotating around tube as necessary to heat tube evenly. Add braze material to the joint while moving torch around joint to flow braze material around circumference.

•

After braze material flows around joint, move torch to heat Area 3. This will draw the braze material down into the joint. The time spent heating Area 3 should be minimal.

• As with any brazed joint, overheating may be detrimental to the final result.

‘Hipot’ (AC High Potential) Testing

Copeland Scroll compressors are configured with the motor down and the pumping components at the top of the shell. As a result, the motor can be immersed in refrigerant to a greater extent than hermetic reciprocating compressors when liquid refrigerant is present in the shell. In this respect, the scroll is more like semi-hermetic compressors that have horizontal motors partially submerged in oil and refrigerant.

When Copeland Scroll compressors are hipot tested with liquid refrigerant in the shell, they can show higher levels of leakage current than compressors with the motor on top. This phenomenon can occur with any compressor when the motor is immersed in refrigerant.

The level of current leakage does not present any safety issue. To lower the current leakage reading, the system

Copeland Scroll Compressor Functional Check: A functional compressor test during which the suction service valve is closed to check how low the compressor will pull the suction pressure is not a good indication of how well a compressor is performing. Such a test will damage a scroll compressor in a few seconds.

The following diagnostic procedure should be used to evaluate whether a Copeland Scroll compressor is functioning properly:

1. Proper voltage to the unit should be verified.

2. Determine if the internal motor overload has opened or if an internal motor short or ground fault has developed. If the internal overload has opened, the compressor must be allowed to cool sufficiently to allow it to reset.

3. Check that the compressor is correctly wired.

4. Proper indoor and outdoor blower/fan operation should be verified.

5. With service gauges connected to suction and discharge pressure fittings, turn on the compressor. If suction pressure falls below normal levels the system is either low on charge or there is a flow blockage in the system.

6. Three phase compressors – If suction pressure does not drop and discharge pressure does not rise to normal levels, reverse any two of the compressor power leads and reapply power to make sure the compressor was not wired to run in reverse. If pressures still do no move to normal values, either the reversing valve (if so equipped) or the compressor is faulty. Reconnect the compressor leads as originally configured and use normal diagnostic procedures to check operation of the reversing valve.

7. To test if the compressor is pumping properly, the compressor current draw must be compared to published compressor performance curves using the operating pressures and voltage of the

AE4-1372 R5 system. If the measured average current deviates more than +/-20% from published values, a faulty compressor may be indicated. A current imbalance exceeding 20% of the average on the three phases of a three-phase compressor should be investigated further. A more comprehensive trouble-shooting sequence for compressors and systems can be found in Section H of the

Emerson Climate Technologies Electrical

Handbook, Form No. 6400 .

8. Before replacing or returning a compressor, be certain that the compressor is actually defective.

As a minimum, recheck compressors returned from the field in the shop or depot by testing for a grounded, open or shorted winding and the ability to start. The orange tag in the service compressor box should be filled out and attached to the failed compressor to be returned. The information on this tag is captured in our warranty data base.

Compressor Replacement After a Motor Burn

In the case of a motor burn, the majority of contaminated oil will be removed with the compressor. The rest of the oil is cleaned with the use of suction and liquid line filter driers. A 100% activated alumina suction filter drier is recommended but must be removed after 72 hours. See

AE24-1105 for clean up procedures and AE11-1297 for liquid line filter-drier recommendations. It is highly recommended that the suction accumulator be replaced if the system contains one. This is because the accumulator oil return orifice or screen may be plugged with debris or may become plugged shortly after a compressor failure. This will result in starvation of oil to the replacement compressor and a second failure. The system contactor should be inspected for pitted/burnt contacts and replaced if necessary. It is highly recommended that the run capacitor be replaced when a single phase compressor is replaced.

General Guidelines and More Information

For general Copeland Scroll compressor and CO

2 refrigerant please log in to Online Product Information at

Emerson.com/OPI , refer to the Application Engineering bulletins listed below, or contact your Application

Engineer.

AE4-1294

Megaohms Values of Copeland®

Compressors

AE24-1105 Principles of Cleaning Refrigeration

Systems

AE11-1297 Liquid Line Filter-Driers

AE4-1396 Application Guidelines for Copeland™

Semi-Hermetic Compressors for

Transcritical CO2 Applications

Commercial CO2 Refrigeration Systems Guide

AE4-1372 R5

Table 1 ZO Family Models

Model

Nominal

Horse-power

Displacement

CFH

Capacity

BTU/hr

EER

Weight lb(kg)

TF5

200/230-3Ø-60Hz

200/220-3Ø-50Hz

Motors

TF7

380-3Ø-60Hz

TFD

460-3Ø-60Hz

480/420-3Ø-50Hz

TFE

575-3Ø-60Hz

ZO21K5E

ZO34K3E

ZOD34K3E

ZO45K3E

ZO58K3E

ZOD58K3E

ZO88KCE

ZO104KCE

1.3

2.5

3.5

112

172

228

291

431

498

20,800

32,000

42,700

55,000

85,300

95,500

49 (22)

60 (27)

62 (28)

65 (29)

88 (40)

90 (41)

ZOD104KCE 6 498 95,500 16 90 (41) X X X

Capacity with R-744 at -31°F (-35°C) evap, 14°F (-10°C) cascade cond, 5°F (-15°C) RG, 14°F (-10°C) liquid

Table 2 Qualified Refrigerants and Oils

Qualified Refrigerants CO₂ (R

-744)

Copeland™ Standard Oil

Emkarate RL 68 HB

Servicing Oil

Emkarate RL 68 HB

Note: Refer to form 93-11 for the latest approved refrigerants and lubricants for Copeland products.

Table 3 Crankcase Number Kits

Model

ZO21K5E

ZO34K3E

ZOD34K3E

ZO45K3E

ZO58K3E

ZOD58K3E

ZO88KCE

ZO104KCE

ZOD104KCE

OEM Part # Description

018-0094-00 240V, 40W

Aftermarket #

918-0052-00

018-0094-01 120V, 40W 918-0052-01

018-0094-03 480V, 40W, 21.25" Lead Length 918-0052-03

018-0094-04 575V, 40W, 21.25" Lead Length 918-0052-04

018-0095-00 240V, 70W, 21" Lead Length 518-0024-06

018-0095-01 480V, 70W, 21" Lead Length

018-0095-02 575V, 70W, 21" Lead Length

018-0095-03 240V, 70W, 32" Lead Length

018-0095-04

240V, 70W, 48”

Lead Length

018-0095-05

480V, 70W, 48” Lead Length

018-0095-06 575V, 70W, 48" Lead Length

018-0095-07 120V, 70W, 48" Lead Length

018-0095-08 400V, 70W, 48" Lead Length

018-0095-09 277V, 70W, 21" Lead Length

518-0024-07

518-0024-08

995-0018-00

918-0043-00

918-0043-01

918-0043-02

918-0043-07

AE4-1372 R5

Table 4 OMC CO2 Specifications

SPECIFICATIONS OMC CO2

Maximum Working Pressure (MWP) 1885 PSIG (130 Bar)

Solenoid min/max OPD

Supply Voltage

1/1450 psig

120 V or 220-240V, 50/60 Hz

Solenoid Coil

Current Consumption

EMF

0.15 Amp (120V), 0.07 Amp (220-240V)

Time Delay for Low Level Signal 10 seconds

Time Delay After Setpoint Recovery 5 seconds

Alarm Delay Time (Including Alarm

Contact)

Alar Switch

120 seconds

SPDT

Alarm Contact Rating

Refrigerant Temperature

10A @ 120VAC 50/60Hz, 5A @ 250VAC 50/60 Hz,

3A@ 30 VDC

-40° to 180°F (-40°C to 82.2°C) Maximum

-40° to 120°F (-40°C to 48.9°C) Maximum Ambient Temperature - Storage

Ambient Temperature - Intermittent

Duty

Oil Supply Fitting

-40° to 120°F (-40°C to 48.9°C) Maximum

1/4" Male SAE (Brass)

Figure 1 CO

Low Temp. Subcritical DX System

AE4-1372 R5

Figure 2 Specially designed rubber rommets Kit # 527-0157-00

Figure 3 Oil Management Control OMC-CO2

AE4-1372 R5

Figure 4 Suction Side Pressure Relief Valve Requirements

AE4-1372 R5

Figure 5 Three Phase Power Circuit

Figure 6 - ZO Compressor Operating Envelope

Figure 7 Compressor Electrical Connection

The contents of this publication are presented for informational purposes only and are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. Emerson Climate Technologies, Inc. and/or its affiliates (collectively

"Emerson"), as applicable, reserve the right to modify the design or specifications of such products at any time without notice. Emerson does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Emerson product remains solely with the purchaser or end user.

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Key features

Designed for use in CO2 subcritical refrigeration systems
Available in a variety of models to meet the needs of different applications
High efficiency
Low noise operation
Compact design
Easy installation and maintenance

Frequently asked questions

CO2 is a natural refrigerant with a low global warming potential (GWP) and zero ozone depletion potential (ODP). It is also non-flammable and non-toxic.

Emerson Copeland Scroll compressors are available in a variety of models to meet the needs of different applications. Some of the most popular models include the ZO, ZB, and ZR series.

Emerson Copeland Scroll compressors are easy to install. Detailed installation instructions are included with each compressor.

Emerson Copeland Scroll compressors require minimal maintenance. Regular maintenance tasks include checking the oil level and cleaning the compressor filters.

Emerson Copeland Scroll compressors come with a standard one-year warranty.