Emerson Copeland 2D Series Instruction Manual

Copeland™Semi-Hermetic
Compressors for A2L & A1 Applications
2D*, 3D* & 8D*
Application Guidelines

AGL_HA_ST_Discus_A2L_A1_EN_Rev00
About these guidelines ...............................................................................................1
1Safety instructions ...........................................................................................1
1.1 Icon explanation............................................................................................................... 1
1.2 Safety statements ............................................................................................................ 2
1.3 General instructions ......................................................................................................... 2
2Product description .........................................................................................3
2.1 Compressor range ........................................................................................................... 3
2.2 Nomenclature................................................................................................................... 3
2.3 Nameplate information..................................................................................................... 4
2.4 Application range ............................................................................................................. 4
2.4.1 Qualified refrigerants and oils .............................................................................. 4
2.4.2 Application limits................................................................................................... 5
2.4.3PED category and maximum allowable pressure PS .......................................... 5
2.5 Design features................................................................................................................ 5
2.5.1 Compressor construction ..................................................................................... 5
2.5.2 Compressor cooling ............................................................................................. 5
2.5.3 Liquid injection / Demand cooling ........................................................................ 5
2.5.4 Unloaded start ...................................................................................................... 6
2.5.5 Capacity control.................................................................................................... 7
2.5.6 Oil pump ............................................................................................................... 7
2.5.7 Oil pressure .......................................................................................................... 7
2.5.8 Oil circulation ........................................................................................................ 8
2.5.9 Oil level................................................................................................................. 8
2.5.10 System oil return .................................................................................................. 8
2.6 Dimensions ...................................................................................................................... 9
3Installation ......................................................................................................10
3.1 Compressor handling..................................................................................................... 10
3.1.1Delivery............................................................................................................... 10
3.1.2 Transport and storage ........................................................................................ 10
3.1.3 Positioning and securing .................................................................................... 10
3.1.4 Installation location............................................................................................. 11
3.1.5 Mounting parts.................................................................................................... 11
3.2 Pressure safety controls ................................................................................................ 11
3.2.1 High-pressure protection .................................................................................... 11
3.2.2 Low-pressure protection..................................................................................... 12
3.2.3 Protection of A2L-refrigerant systems operating below atmospheric pressure . 12
3.2.4 Internal pressure relief valve .............................................................................. 13
3.2.5 Oil differential pressure control .......................................................................... 13
3.2.6 Maximum allowable pressures........................................................................... 13
3.3 Brazing procedure.......................................................................................................... 13

AGL_HA_ST_Discus_A2L_A1_EN_Rev00
3.4 Filter screens ................................................................................................................. 14
3.5 Insulation material.......................................................................................................... 14
4Electrical connection ..................................................................................... 15
4.1 General recommendations............................................................................................. 15
4.2 Electrical installation ...................................................................................................... 16
4.2.1 Part-winding motors (YY/Y) – Code A................................................................ 16
4.2.2 Star / Delta motors (Y/∆) – Code E .................................................................... 16
4.2.3 Terminal box jumpers positions ......................................................................... 17
4.3 Terminal box .................................................................................................................. 17
4.4 Electrical protection........................................................................................................ 17
4.5 Compressor protection................................................................................................... 18
4.6 Demand Cooling™......................................................................................................... 19
4.7 Oil differential pressure control ...................................................................................... 21
4.7.1 Electronic oil pressure switch OPS2 .................................................................. 21
4.7.2 Electro-mechanical oil pressure switch – Alco Controls FD-113ZU................... 21
4.8 Crankcase heaters......................................................................................................... 22
4.8.1 70-Watt and 100-Watt heater element ............................................................... 22
4.8.2 200-Watt heater element.................................................................................... 23
5Start-up & operation....................................................................................... 24
5.1 Compressor tightness test ............................................................................................. 24
5.2 System evacuation......................................................................................................... 24
5.3 Preliminary checks – Pre-starting .................................................................................. 24
5.4 Charging procedure ....................................................................................................... 25
5.5 Initial start-up ................................................................................................................. 25
5.6 Minimum run time .......................................................................................................... 26
5.7 Recommended inverter range ....................................................................................... 26
6Maintenance & repair ..................................................................................... 27
6.1 Qualification of workers.................................................................................................. 28
6.2 Preparation and work procedure ................................................................................... 28
6.3 Unbrazing system components ..................................................................................... 28
6.4 Disassembling system components .............................................................................. 28
6.5 Exchanging the refrigerant............................................................................................. 29
6.6 Replacing a compressor ................................................................................................ 29
6.6.1 Compressor replacement ................................................................................... 29
6.6.2 Compressor return procedure for A2L systems ................................................. 30
6.7 Lubrication and oil removal............................................................................................ 30
6.8 Oil additives ................................................................................................................... 31
7Troubleshooting............................................................................................. 32
7.1 Lubrication ..................................................................................................................... 32
7.2 Oil dilution ...................................................................................................................... 32

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7.3 Inadequate suction superheat ....................................................................................... 32
7.4 Acid formation ................................................................................................................ 32
7.5 Inadequate compressor cooling..................................................................................... 32
7.6 High discharge temperatures......................................................................................... 33
7.7 Motor burnout due to undersized contactors ................................................................. 33
7.8 Motor burnout due to by-passed or disconnected protectors ........................................ 33
8Dismantling & disposal.................................................................................. 33
Appendix 1: Compressor connections..................................................................... 34
Appendix 2: Tightening torques (Nm) ...................................................................... 36
DISCLAIMER ..............................................................................................................37

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About these guidelines
The purpose of these guidelines is to provide guidance in the application of Copeland™ semi-
hermetic compressors in users’ systems. They are intended to answer the questions raised while
designing, assembling and operating a system with these products.
Besides the support they provide, the instructions listed herein are also critical for the proper and
safe functioning of the compressors. The performance and reliability of the product may be impacted
if the product is not used according to these guidelines or is misused.
These application guidelines cover stationary applications only. For mobile applications, please
contact the Application Engineering department at Emerson as other considerations may apply.
1 Safety instructions
Copeland semi-hermetic compressors are manufactured according to the latest relevant European
safety standards. Particular emphasis has been placed on the user’s safety.
Copeland semi-hermetic 2D*, 3D* and 8D* compressors are intended for installation in systems in
accordance with the following directives and regulations:
Machinery Directive MD 2006/42/EC
Supply of Machinery (Safety) Regulation 2016
Low Voltage Directive LVD 2014/35/EU
Electrical Equipment (Safety) Regulation 2016
They can be used in the EU only if they have been installed in systems according to instructions and
conform to the corresponding provisions of legislation. For relevant standards please refer to the
Manufacturer’s Declaration, available at www.climate.emerson.com/en-gb.
NOTE:Only dedicated compressors are allowed to be used with flammable refrigerants.
Emerson marks all compressors that are qualified for flammable refrigerants with a sticker
indicating the usage of such refrigerants. Systems using flammable refrigerants must be
executed correctly while observing safety rules, as specified in corresponding safety
standards such as, but not limited to EN 378. They must comply with any and all applicable
legislation and regulations. Ensuring compliance remains the user’s responsibility.
The Material Safety Datasheet (MSDS) for the individual refrigerant shall be considered when
working with these types of refrigerant - please check the document provided by the gas supplier.
These instructions shall be retained throughout the lifetime of the compressor.
You are strongly advised to follow these safety instructions.
1.1 Icon explanation
WARNING
This icon indicates instructions to
avoid personal
injury and material
damage.
Fire hazard
This icon indicates a risk of flammable
atmosphere.
High voltage
This icon indicates operations with a
danger of electric shock.
CAUTION
This icon indicates instructions to
avoid property damage and possible
personal injury.
Danger of burning or frostbite
This icon indicates operations with a
danger of burning or frostbite.
IMPORTANT
This icon indicates instructions to
avoid malfunction of the compressor.
Explosion hazard
This icon indicates operations with a
danger of explosion.
NOTE
This word indicates a
recommendation for easier operation.
Danger of explosive atmosphere
This icon indicates a risk of explosive
atmosphere.

2 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
1.2 Safety statements
Refrigerant compressors must be employed only for their intended use. The system has
to be labelled according to the applicable standards and legislation.
Only qualified and authorized RACHP (refrigeration, air conditioning and heat pump)
personnel are permitted to install, commission and maintain this equipment.
Electrical connections must be made by qualified electrical personnel.
All valid standards for connecting electrical and refrigeration equipment must be
observed.
The national legislation and regulations regarding personnel protection must be observed.
Additional requirements and statements for A2L-refrigerant compressor/systems:
Only competent personnel (as specified in EN 13313) qualified for flammable refrigerant
handling are permitted to commission, initiate and maintain the compressor/refrigeration
systems using flammable refrigerant; non-trained personnel, including the user, are not
allowed to do so and must call on an expert.
The maximum refrigerant charge is specified in standards such as, but not limited to
EN 378, EN 60335-2-40 and EN 60335-2-89. The system designer shall implement all safety
measures defined by the applicable standards and the maximum refrigerant charge shall
not be exceeded.
If a flammable atmosphere is detected, immediately take all necessary precautions to
mitigate the risk as determined in the risk assessment.
Use personal safety equipment. Safety goggles, gloves, protective
clothing, safety boots and hard hats should be worn where
necessary.
1.3 General instructions
WARNING
Pressurized system! Serious personal injuries and/or system
breakdown! Accidental system start before complete set-up must be avoided.
Never leave the system unattended without locking it out electrically when it is
on vacuum and has no refrigerant charge, when it has a holding charge of
nitrogen, or when the compressor service valves are closed.
WARNING
System breakdown! Personal injuries!
Only approved refrigerants and
refrigeration oils must be used.
WARNING
High shell temperature! Burning! Do not touch the compressor and piping
until they have cooled down. Ensure that other materials in the area of the
compressor do not come into con
tact with it. Lock and mark accessible
sections.
CAUTION
Overheating! Bearing damage!
Do not operate compressor without
refrigerant charge or without it being connected to the system.
CAUTION
Contact with refrigerant oil! Material damage! Polyolester (POE) lubricant
must be handled carefully and the proper protective equipment (gloves, eye
protection, etc.) must be used at all times. Refrigerant oil must not come into
contact with any surface or material that it might damage, including without
limitation, certain polymers, eg, PVC/CPVC and polycarbonate.
IMPORTANT
Transit damage! Compressor malfunction! Use original packaging. Avoid
collisions and tilting.

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 3
2 Product description
2.1 Compressor range
These application guidelines cover Copeland semi-hermetic compressor models 2D*, 3D* and 8D*
with displacement ranging from 16.8 to 181 m3/h. The optimized valve plate design of these
compressors provides the highest energy efficiency.
Copeland semi-hermetic compressors are suitable for a wide range of applications in the form of
either single compressors, condensing units or as multi-compressor equipment.
Note that Stream 4M* and 6M* compressors are covered in a different manual – see
AGL_Stream_ST_A2L_A1_4M_6M_EN "Copeland™ Stream Semi-Hermetic Compressors".
NOTE: The compressor is only one component which must be combined with many others to
build a functional and efficient refrigeration system. Therefore, the information in this manual
relates to Copeland semi-hermetic compressors with standard equipment and accessories
only.
2.2 Nomenclature
The model designation contains the following technical information about the standard and Discus
compressors:
Figure 1: Nomenclature
The 2D*, 3D* and 8D* compressors have been modified internally to support operation with A2L
refrigerants. The modified models can be identified by the new design revision number in the
nomenclature – see also Table 1 below. Only the compressors marked with the new design revision
numbers are approved for operation with A2L refrigerants, or alternatively with A1 refrigerants. The
compressor models with the revision numbers of the old design are not qualified for operation with
A2L refrigerants and can only be operated with A1 refrigerants.
"Old" design revision
number (A1 refrigerants)
"New" design revision number
(A2L + A1 refrigerants)
2D*3
2D*4
3D*5
3D*6
8D*6 8D*
7
Table 1: Design revision numbers and corresponding refrigerant safety classes
The qualification and suitability for A2L operation and the changeover to updated design
revision numbers in the nomenclature are of application from serial number 23B** (production
date February 2023) onwards.

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2.3 Nameplate information
All important information for identification of the compressor is printed on the nameplate.
The year and month of production are shown on the nameplate as part of the serial number (Jan =
A, Feb = B, … Dec = L).
Figure 2: Examples of nameplate for 2D* & 3D* compressors
Figure 3: Example of nameplate for 8D* compressors
2.4 Application range
2.4.1 Qualified refrigerants and oils
IMPORTANT
Some refrigerant blends (for example R454C, R455A and R454A)
have a
significant temperature glide.
It is essential that this glide be carefully
considered when adjusting pressure and superheat controls.
NOTE: R454C, R455A and R454A are classified as A2L (mildly flammable) refrigerants.
NOTE: For applications with A1 refrigerants (R448A, R449A, R407A, R407F, R404A, R407C,
R513A, R450A, R134a and R22), the flammable refrigerant sticker is not of application and can
be removed from the compressor.
Compressors 2D*, 3D* & 8D*
Qualified
refrigerants
R454C, R455A
& R454A
R448A, R449A, R407A,
R407F, R404A, R407C,
R513A, R450A & R134a
R22
Qualified oils
(factory charged)
RL32 3MAF RL32 3MAF Suniso 3 GS
Servicing oils RL32 3MAF RL32 3MAF
Mobil EAL Arctic 22 CC
Shell 22-12, Suniso 3 GS
Fuchs Reniso KM 32
Capella WF 32
Table 2: Qualified refrigerants and oils for recharging and topping up
Oil recharge values can be taken from Copeland Select software available at
www.climate.emerson.com/en-gb.
To recharge:
When the compressor is completely empty of oil, the amount of oil to be "recharged" is typically
0.12 litre less than the original oil charge (oil will already be present in the system).
To top up:
During commissioning, planned maintenance or servicing, add oil so that the compressor oil level
is between min ¼ and max ¾ of the sight glass.

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 5
2.4.2 Application limits
CAUTION
Inadequate lubrication! Compressor breakdown! The superheat at the
compressor suction inlet must always be sufficient to ensure that no refrigerant
droplets enter the compressor. For a typical evaporator-
expansion valve
configuration a minimum stable superheat of at least 10 K is required.
For application envelopes and technical data, please see Select software available at
www.climate.emerson.com/en-gb.
2.4.3 PED category and maximum allowable pressure PS
The Pressure Equipment Directive PED 2014/68/EU does not apply to 2D*, 3D* and 8D* semi-
hermetic compressors.
The pressure PS is the maximum allowable pressure at the low- and high-pressure sides of the
compressor. The maximum pressure value PS for the individual compressor type is printed on the
nameplate of the compressor. Safety is established in compliance with the relevant standards
applicable to the given product. Also refer to section 3.2.6 "Maximum allowable pressures".
Compressor
PS
High-pressure side
PS
Low-pressure side
2D*, 3D* & 8D*
32.5 bar(g)
22.5 bar(g)
Table 3: Maximum allowable pressures
2.5 Design features
2.5.1 Compressor construction
The semi-hermetic compressors covered in these guidelines are suction-gas cooled compressor
models 2D*, 3D* and 8D* with 2, 3 and 8 cylinders respectively and a displacement between
16.8 and 181 m³/hr. They are fitted with Discus™ valve plates.
Each cylinder head has a plugged 1/8" - 27 NPTF tapped hole for connecting a high-pressure switch.
The high-pressure switches must be calibrated and tested before putting the compressor into service.
They must stop the compressor if the allowable pressure is exceeded.
The complete cylinder head is under discharge pressure.
2.5.2 Compressor cooling
With suction-gas cooled compressors, the motor is cooled by the incoming refrigerant, which enters
the compressor and is then passed over the motor area. An additional fan may be required depending
upon the operating conditions – see Select software at www.climate.emerson.com/en-gb.
2.5.3 Liquid injection / Demand cooling
WARNING
Ignition source in a potentially flammable atmosphere! Fire hazard! The
solenoid valve of the liquid injection is not an ignition source during normal
operation in an A2L-refrigerant system but could become one if not installed
properly. Never operate the solenoid coil when not positioned on the solenoid
valve. Secure the installation with a screw.
Liquid injection may be required for low-temperature applications in order to keep the compressor
within safe discharge temperature limits.
Additional liquid cooling can be applied in the low-temperature model versions of 2D* and 3D*
compressors. With this solution, an additional discharge temperature sensor, a separate Demand
Cooling driver and a liquid injection valve kit work together.
For more information also see Section 4.6 "Demand Cooling™".
NOTE: For corresponding application envelopes, please see Select software available at
www.climate.emerson.com/en-gb.

6 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
2.5.4 Unloaded start
WARNING
Ignition source in a potentially flammable atmosphere! Fire hazard! The
solenoid valve of the unloaded start is not an ignition source during normal
operation in an A2L-refrigerant system but could become one if not installed
properly. Never operate the solenoid coil when not positioned on the solenoid
valve. Secure the installation with a screw.
Unloaded start is mainly required for compressors connected for part-winding start (for example with
motor version AWM) or star-delta start (motor version EWM).
2.5.4.1 Unloaded start for 2D* and 3D* models
As a result of the compressor design of the 2D* and 3D* models, the components for unloaded start
are mounted outside the compressor housing. The unloaded start kit consists of a very short bypass
line that connects the high-pressure side of the compressor to the suction side. A solenoid valve is
installed in this bypass line.
When the compressor is switched on, the solenoid valve opens the bypass line and holds it open
during the starting phase. The refrigerant vapour is short-circuited without any significant increase in
pressure, and the motor is unloaded.
After completion of the starting procedure, ie, after energizing of the second part-winding or
changeover from star to delta or short-circuiting of starting resistors, the solenoid valve is de-
energized, closing off the bypass line.
A Non-Return Valve (NRV) must be installed in the discharge line to prevent the refrigerant from
flowing back from the condenser to the suction side.
The kit consists of the following parts:
Figure 4: Unloaded start components for 2D* and 3D* models
2.5.4.2 Unloaded start for 8D* models
8D* compressors can be equipped with an internal unloaded start system, to be ordered as an option.
The compressor prepared for unloaded start is supplied with a special cylinder head. The control
valve and coil are positioned on the top of the cylinder head. An additional check valve must be
installed in the discharge piping. Recommended inbuild position for the check valve is approximately
50-100 cm to the compressor discharge connection.
A. Standard operation B. Unloaded start operation
Figure 5: Unloaded start components & operation for 8D* models
1Special cylinder head
2Solenoid
3Valve
4Spring-loaded control piston
5 Suction side
6High side in the cylinder head
7 Valve plate
1
6
5
2
3
4
7
1
1
1 x Pipe assembly and valve body (1)
1 x Rotalock stub (2)
1 x Rotalock seal (3)
1 x Gasket - flange to cylinder head (4)
1 x Gasket - flange to Rotalock valve (4)
1 x Solenoid valve coil (5)
1 x Check valve
x Screws ½" – 13 UNC X 2¾"

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Usually, the unloaded start is activated once for about 5-10 seconds shortly before compressor start
and then kept closed during operation. The unloaded start solenoid valve opens a suction channel
in the valve plate and the pressure in the discharge line equalizes to the suction side.
Assembly
Installation of the modified cylinder head and valve plate for unloaded start is only possible at certain
positions on the compressor. Therefore all 8D* compressor models have fixed cylinder head
positions for unloaded start.
Figure 6: Unloaded start position for 8D* models
2.5.5 Capacity control
WARNING
Ignition source in a potentially flammable atmosphere! Fire hazard! The
solenoid valve of the capacity control is not an ignition source during normal
operation in an A2L-refrigerant system but could become one if not installed
properly. Never operate the solenoid coil when not positioned on the solenoid
valve. Secure the installation with a screw.
A mechanical capacity control is available for 8D* compressors. The system used is blocked suction.
The suction port of the valve plate will be closed by a control piston. When an 8D* compressor is
ordered with capacity control, it is equipped with one or two special cylinder heads. The capacity
control valves with coils are positioned on the top of the cylinder head. Not all cylinder bank positions
are possible for the capacity control cylinder head.
Capacity control must be fitted in the following positions:
8D* 1st step 25 % Lower cylinder head on terminal box side
8D* 2nd step 50 % Lower cylinder head on discharge valve side
Figure 7: Capacity control position on 8D* models
2.5.6 Oil pump
All 2D*, 3D* and 8D* compressors are equipped with an external oil pump. The oil pump will always
work in the correct direction of rotation, regardless of the rotation direction of the compressor. The
compressors are designed to accommodate fittings for an OPS2 oil safety system (OPS2 oil sensor
included in the oil pump) or any conventional oil pressure switch.
2.5.7 Oil pressure
Normal oil pressure is between 1 and 4.2 bar higher than crankcase pressure. Net oil pressure can
be read by connecting two pressure gauges to the compressor and comparing the readings. One

8 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
gauge should be connected to the oil pump. The second gauge should be connected to the
crankcase (oil service plug or any other crankcase connection plug).
NOTE:The pressure measured on the suction service valve, where the refrigerant enters the
compressor housing, does not correspond to the crankcase pressure and should not be used
as a reference for the indication of oil differential pressure.
2.5.8 Oil circulation
Oil returns with the suction gases through a suction strainer and separates in the motor chamber
reaching the crankcase by way of oil return relief valve in the partition between motor housing and
crankcase. This relief valve closes on compressor start-up due to the pressure difference arising
between motor side and crankcase, thus slowing down pressure decrease in the crankcase over a
certain period of time. It reduces the foaming of the oil/refrigerant mixture that would occur if the
pressure decreased rapidly.
The valve does not reopen until the pressure has been equalized by means of a crankcase ventilating
valve. This second valve connects the crankcase and suction side cylinder head. It reduces the
pressure difference by means of a very small bore in the plate of the valve so slowly that oil foams
less and only limited oil/refrigerant foam is transferred to the oil pump.
2.5.9 Oil level
The 2D*, 3D* and 8D* compressors are supplied with sufficient oil for normal operation – see
individual oil quantities in Select. The optimum oil level should be checked by operating the
compressor until the system is stable then comparing the sight glass reading with the corresponding
oil level in Figure 8 below. For 8-cylinder compressors, a higher oil level may be accepted if an oil
regulator is used.
2D*, 3D* 8D*
Figure 8: Oil level
2.5.10 System oil return
CAUTION
Inadequate lubrication! Bearing and moving parts destruction! Ensure
adequate oil return from the system into the compressor at any time. No liquid
refrigerant return to the compressor. Liquid refrigerant dilutes the oil, could
wash the oil off the bearings and moving parts and could lead to overheating
and compressor failure.
The system piping must be carefully designed to ensure sufficient refrigerant gas velocity, so that oil
returns to the compressor at all times and conditions. Individual piping diameter calculation depends
on the refrigerant properties, pressure level, mass flow, and density.
Once a new system design is set and assembled, a functional test is required. The functional test
includes a qualification for the general system oil return. Systems with multiple compressors (two,
three, or more) require additional oil balancing qualification between the parallel compressors.
System engineers should review the system design and operation to identify the critical conditions
and to check oil return and oil balancing. Typically, the following situations should be considered:
In single compressor systems:to check oil return, testing conditions shall be at minimum mass
flow and minimum density of suction gas in continuous and frequent start/stop-cycling.
In multiple compressor systems:to check oil return and oil balancing in the tandem or rack,
testing conditions shall be at the corner points of the system application envelope in continuous
and frequent start/stop-cycling.
The system shall also be tested with regards to liquid refrigerant flood-back and the superheat
level of the refrigerant gas at compressor suction.
These checks should be carried out for standard operation, but also for special conditions such as
compressor frequent start/stop, compressor start after long off time with migration, defrost, low load,
load changes, fans or pumps cycling at low load and more.

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 9
2.6 Dimensions
Figure 9: 2D* compressors dimensions
Figure 10: 3D* compressors dimensions
Figure 11: 8D* compressors dimensions

10 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
3 Installation
WARNING
High pressure! Injury to skin and eyes possible! Be careful when opening
connections on a pressurized item.
3.1 Compressor handling
3.1.1 Delivery
Please check whether the delivery is correct and complete. Any deficiency should be reported
immediately in writing. Standard delivery:
Suction and discharge shut-off valves
Oil charge, oil sight glass
Mounting kit
Motor protection system
Holding charge up to 2.5 bar(g) (dry air)
Compressors are individually packed and may be delivered on pallets depending on quantity and
size. Cooling fans are delivered in separate boxes. Accessories may be mounted or delivered loose.
Solenoid valves are never mounted.
3.1.2 Transport and storage
WARNING
Risk of collapse! Personal injuries!
Move compressors only with
appropriate handling equipment according to weight. Keep in the upright
position. Respect stacking loads according to Figure 12. Check the tilting
stability and if needed take action to ensure the stability of the stacked loads.
Keep the packaging dry at all times.
Respect the maximum number of identical packages which may be stacked on one
another, where "n" is the limiting number:
Transport: n = 1 for 8D* / n = 2 for 3D* / n = 3 for 2D*
Storage: n = 1 for single box 8D* / n = 2 for 2D* & 3D*
Figure 12: Maximum stacking loads for transport and storage
NOTE: The compressor is pre-charged with dry air to avoid any moisture contamination.
3.1.3 Positioning and securing
IMPORTANT
Handling damage! Compressor malfunction!
Only use the lifting eyes
whenever the compressor requires positioning. Using discharge or suction
connections for lifting may cause damage or leaks.
If possible, the compressor should be kept horizontal during handling.
In order to avoid refrigerant leaks or other damage the compressors should not be lifted by the service
valves or other accessories.
2D* 3D*
max. 140 kg max. 175 kg

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 11
8D*Lifting eye
max. 350 kg ½" – 13 UNC
Figure 13: Compressor lifting methods
3.1.4 Installation location
Ensure the compressors are installed on a solid level base.
For multiple compressor parallel configurations, the compressors must be positioned completely
vertically on a totally horizontal surface or rail.
3.1.5 Mounting parts
To minimize vibration and start/stop impulses flexible mounting should be used. For this purpose one
specific set of spring mounting parts is delivered with each compressor model.
A compressor may be rigidly mounted, ie, without springs. In this case more shock and vibration
loading will be transmitted to the frame.
If the installation requires a very high level of vibration absorption, additional vibration absorbers –
available on the market – can be fitted between the rails and the foundation.
To ensure proper lubrication of moving parts, the compressor should be installed horizontally on both
axes.
Transport clamp Transport position Operating position Grommets for twin
compressors
Figure 14: Position of vibration dampers during transport and operation
3.2 Pressure safety controls
3.2.1 High-pressure protection
Applicable regulations and standards, for example EN 378-2, shall be followed to apply appropriate
control and ensure that the pressure never exceeds the maximum limit.
High-pressure protection is required to stop the compressor operating outside the allowable pressure
limits. The high-pressure control must be installed correctly, which means that no service valve is
allowed between the compressor and the pressure protection.
The high-pressure cut-out setting shall be determined according to the applicable standard, the type
of system, the refrigerant and the maximum allowable pressure PS.
The high-pressure cut-out should have a manual reset feature for the highest level of system
protection.

12 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
3.2.2 Low-pressure protection
CAUTION
Operation outside the application envelope! Compressor breakdown! A
low-
pressure protection shall be fitted in the suction line to stop the
compressor when it operates outside the envelope limits. Do not bridge or by-
pass the low-pressure limiter.
CAUTION
Low suction pressure operation! Compressor damage! Do not operate
compressor with a restricted suction or with the low-pressure limiter bridged.
Do not operate compressor at pressures that are not allowed by the operating
envelope. Allowing the suction pressure to drop below the envelope limit for
more than a few seconds may overheat the pistons and cause damage to
parts.
Applicable regulations and standards shall be followed to apply appropriate control and ensure that
the pressure is always above the required minimum limit.
The low-pressure control must be installed correctly into the suction line, which means that no service
valve is allowed between the compressor and the pressure protection.
The minimum cut-out setting shall be determined according to the refrigerant and the allowed
operation envelope – see Select software at www.climate.emerson.com/en-gb.
The low-pressure cut-out should have a manual reset feature for the highest level of system
protection.
3.2.3 Protection of A2L-refrigerant systems operating below atmospheric pressure
WARNING
Operation below atmospheric pressure! Fire hazard!
During operation
below atmospheric pressure, a flammable mixture can form inside the system.
Ensure system tightness to prevent any ingress of air.
CAUTION
Operation outside the application envelope! Compressor breakdown! A
low-pressure protection shall
be fitted in the suction line to stop the
compressor when it operates outside the envelope limits.
CAUTION
Low suction pressure operation! Compressor damage! Do not operate
compressor with a restricted suction or with the low-pressure limiter bridged.
Do not operate compressor at pressures that are not allowed by the operating
envelope. Allowing the suction pressure to drop below the envelope limit for
more than a few seconds may overheat the pistons and cause damage to
parts.
Special requirements for safety and tightness apply to 2D*, 3D* or 8D* compressor systems that are
to be operated below atmospheric pressure. The following precautions must be observed:
Check all the critical points on the system and piping connections; tightness has to be ensured
also at very low pressure.
Minimum absolute working pressure: 0.5 bar.
The installation of mechanical high-pressure and low-pressure cut-outs is mandatory. For
systems provided with a service shut-off valve on the discharge side of the compressor, only
mechanical pressure cut-outs shall be used. Electronic pressure limiters, which could cause
delayed sensor response, are not allowed.
The high- and low-pressure cut-outs must be installed correctly on the discharge and suction
lines, which means that no service valve is allowed between the compressor and the pressure
protection (refer to EN 378 or ISO 5149).
A discharge temperature control is mandatory to stop the compressor when the maximum
discharge temperature is exceeded.
Additional warning notices shall be affixed to any system equipped with shut-off valves. The
warnings must contain instructions to open the shut-off valves completely after each repair or

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 13
maintenance work. The compressors may only be energized when the safety measures (high-
and low-pressure cut-outs and discharge temperature cut-out) have been checked and verified
to be operational.
NOTE: All of the above points must be fulfilled. If any of them cannot be met, the compressor
must not be operated below atmospheric pressure.
3.2.4 Internal pressure relief valve
8D* compressors are equipped with an internal pressure relief valve placed between the suction
chamber and the discharge chamber. The valve protects the compressor against bursting if the
discharge shut-off valve is accidentally fully closed.
NOTE: The valve will not protect the installation against dangerous system pressures!
Before operating the compressors, the pressure switches and other safety devices must be installed
correctly. The maximum allowable pressures must not be exceeded.
Each cylinder head has a plugged 1/8" – 27 NPTF tapped hole for connecting a high-pressure switch.
3.2.5 Oil differential pressure control
The oil pressure switch breaks the control circuit when the pressure difference between the oil pump
outlet and the crankcase is too low. If the oil differential pressure drops below the minimum
acceptable value the compressor will be stopped after a 120-second delay. After having solved the
problem the control has to be reset manually. The switch must be properly adjusted and tamper-
proof.
The following oil pressure switches can be delivered as accessories:
Electronic oil pressure switch OPS2
Mechanical oil pressure switch Alco Controls FD-113ZU, applicable only with A1 refrigerants
For more information on the oil pressure switches and wiring diagrams, see Section 4.7 "Oil
differential pressure control".
NOTE: Proper oil pressure safety control with an approved switch is a condition of warranty!
3.2.6 Maximum allowable pressures
The maximum allowable pressures according to EN 12693 are shown on the compressor nameplate.
They are obligatory and must not be exceeded.
High-pressure side (HP): 32.5 bar (g)
Low-pressure side (LP): 22.5 bar (g)
NOTE: The compressor operating range may be restricted for various reasons. Check the
application range limitations in Select software at www.climate.emerson.com/en-gb.
3.3 Brazing procedure
WARNING
Air/flammable refrigerant mixture! Creation of a potentially flammable
atmosphere! Fire hazard! Remove all refrigerant before opening the system.
When working on a refrigerant-filled system, make sure to follow the safety
and working instructions given in Chapter 6 "Maintenance & repair".
WARNING
High temperature! Burning!
Proceed with caution when brazing system
components. Do not touch the compressor until it has cooled down. Ensure
that other materials in the area of the compressor do not come into contact
with it.
CAUTION
Blockage! Compressor breakdown! Maintain a flow of oxygen-free nitrogen
through the system at very low-pressure during brazing. Nitrogen displaces
the air and prevents the formation of copper oxides in the system. If allowed
to form, the copper oxide material can later be swept through the system and
block screens such as those protecting capillary tubes, thermal expansion
valves, and accumulator oil return orifices.

14 AGL_HA_ST_Discus_A2L_A1_EN_Rev00
CAUTION
Contamination or moisture! Bearing failure! Do not remove the connection
plugs until the compressor is set into the unit. This minimises any entry of
contaminants and moisture.
Refer to Figure 15 and procedure below for the brazing of the suction and discharge lines:
Flushing oxygen-free nitrogen through the piping
during the brazing process is recommended for
applications with A1 refrigerants and mandatory for
applications with flammable A2L refrigerants.
The copper-coated steel tubes on semi-hermetic
compressors can be brazed in approximately the same
manner as any copper tube.
Recommended brazing material: any Silfos material is recommended, preferably with a minimum
of 5 % silver. However, 0 % silver is acceptable. For brazing connections where dissimilar or ferric
metals are joined a silver alloy rod with a minimum silver content of 30 % shall be used being
either flux-coated or with a separate flux.
Be sure tube fitting inner and outer surfaces are clean prior to assembly.
Using a double-tipped torch, apply heat in area 1.
As the tube approaches brazing temperature, move the torch flame to area 2.
Heat area 2 until braze temperature is attained, moving the torch up and down and rotating around
the tube as necessary to heat the tube evenly. Add braze material to the joint while moving the
torch around the joint to flow braze material around the circumference.
After the braze material flows around the joint, move the 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.
3.4 Filter screens
CAUTION
Screen blocking! Compressor breakdown! Use screens with at least
0.6 mm openings.
The use of screens finer than 30 x 30 meshes (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
thermal 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.
3.5 Insulation material
Insulation material is commonly used in a system to insulate the suction line, suction accumulator,
expansion valve bulb or discharge line thermostat. When choosing the insulation material for A2L
applications, particular attention shall be paid to its non-electrostatic properties, as it could be a
potential ignition source.
Figure
15: Brazing areas

AGL_HA_ST_Discus_A2L_A1_EN_Rev00 15
4 Electrical connection
4.1 General recommendations
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.
When the compressor is shipped the motor protector is mounted in the terminal box. The thermistors
are factory connected. The power supply and the control circuit must be wired according to the wiring
diagram on the inside of the terminal box cover. For more information on the wiring diagrams, please
also visit www.climate.emerson.com/en-gb.
The knockouts on the terminal box have to be removed before the electrical glands can be installed.
First make sure that the terminal box is closed with its cover. Emerson recommends to use a subland
twist driller to avoid any damage to the box while removing the knockouts.
Figure 16: Terminal box preparation for cable gland fitting
Position at
terminal box
Hole diameter
at terminal box (mm)
Cable bushing
metric
Outside
diameter (mm)
1
20.6
M20 x 1.5
20
2
32.5
M32 x 1.5
32
3
50.5
M50 x 1.5
50
4
63.5
M63 x 1.5
63
Table 4: Characteristics of the holes for cable bushings
The protection class of each terminal box according to IEC 60529 is given in Table 5hereunder.
Also refer to Section 4.3 "Terminal box".
Models Class Option
2D*
IP54
-
3D*
IP54
IP56
8D*
IP54
IP56
Table 5: Protection class
For safety reasons, Emerson recommends that the electrical installation be executed in compliance
with standard EN 60204-1 and/or other standards and regulations of application when dealing with
A2L mildly flammable refrigerants such as R454C, R455A and R454A.
When installing 2D*, 3D* or 8D* compressors in A2L systems, the following measures must be taken:
To ensure the wires are properly terminated, the correct terminal and clamping tool for the
selected wire size must be used.
The ground wiring must conform to local regulations and codes of practice (only the provided
parts must be used).
The grounding screw must be torqued to 4.5 to 5.7 Nm.
A cable strain-relief device must be added.
Cable and wires must be protected against sharp edges.
Twist driller
2D*
3D* & 8D*