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AE4-1365
User Manual
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Emerson AE4-1365 User Manual

© 2020 Emerson Climate Technologies, Inc.
1
TABLE OF CONTENTS
Safety
Safety Icon Explanation
.......................................... 3
Introduction ................................................................ 5
Application Considerations .......................................... 5
Air Conditioning System Suction Line Noise and
Three Phase Scroll Compressor Electrical Phasing
Application Tests ........................................................ 11
Field Application Test ............................................. 12
Assembly Line Procedures ......................................... 12
Installing the Compressor ...................................... 12
Assembly Line Brazing Procedure ......................... 13
Tandem Assembly ................................................. 13
Pressure Testing .................................................... 13
Assembly Line System Charging Procedure ......... 13
“Hipot” (AC High Potential) Testing ........................ 14
Final Run Test ........................................................ 14
Unbrazing System Components ............................ 14
Service Procedures .................................................... 14
Copeland Scroll Compressor Functional Check .... 14
Compressor Replacement After a Motor Burn ....... 15
Start-Up of a New or Replacement Compressor ... 15
Figures & Tables
Figure 1 - Operating Envelope ................................... 16
Figure 2 - Oil Dilution Chart ........................................ 17
Figure 3 - ASTP Label ................................................ 18
Figure 4 - Crankcase Heater ...................................... 18
Figure 5 - Typical ZP*KC Tandem ............................. 19
Figure 6 - Tilted Tandem ............................................ 19
Figure 7- Scroll Suction Tube Brazing........................ 20
Figure 8- How Scroll Works ........................................ 21
Table 1 - Field Application Test .................................. 22
Table 2 - Design Configurations ................................. 22
Table 3 - Compressor Refrigerant Charge Limits ...... 22
Table 4 - Compressor Accessories ............................ 23
Table 5 - PED Details ................................................. 25
AE4-1365 R5
February 2020
5 to 12 Ton ZP*K3, ZP*KC, and ZP*KW R-410A
Copeland Scroll™ Compressors for Air Conditioning
© 2020 Emerson Climate Technologies, Inc.
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AE4-1365 R5
Revision Tracking R5
Pg.6 – Added Information on the Pressure Equipment Directive certification Pg.6 – Updated Discharge Check Valve information Pg.11 – Deleted the Tandem Application section. Note added to refer to AE4-1430 for multiples. Pg.22 – Table 3, Tandem Charge Limit removed Pg.23 – Table 4, Terminal Block part numbers updated. Comfort Alert Module Applications Pg.23 – Table 5, PED Details Added.
© 2020 Emerson Climate Technologies, Inc.
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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 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.
DANGER
WARNING
CAUTION
NOTICE
CAUTION
© 2020 Emerson Climate Technologies, Inc.
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I
nstructions 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.
© 2020 Emerson Climate Technologies, Inc.
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Introduction
The 70 frame ZP*K3 and ZP*KC Copeland Scroll™ compressors are designed for a wide variety of light commercial cooling and heat pump applications. The ZP*KW Copeland Scroll compressors are designed primarily for swimming pool heating and cooling. This bulletin describes the operating characteristics, design features, and application requirements for these models.
For additional information, please refer to the online product information accessible from the Emerson website at
Emerson.com/OPI.
Operating principles of
the Copeland Scroll compressor are described in
Figure 8
of this bulletin.
The ZP*K3 and ZP*KC scrolls range in size from 50,000 to 57,000 Btu/hr (14.7 to 16.7 kW) and 61,000 to 147,000 Btu/hr (17.9 to 43.1 kW) respectively. These models include all of the standard 50 and 60 Hertz, three phase voltages and some single phase voltages. The ZP*KW scrolls are single-phase only scrolls in 70,000 and 83,000 Btu/hr (20.5 and 24.3 kW) displacements.
All of the compressors covered in this bulletin are in the 70 frame family (7" diameter shell) and include a number of features outlined in the matrix below.
Nomenclature
The model numbers of the Copeland Scroll compressors include the approximate nominal 60 Hz capacity at standard operating conditions. An example would be the ZP67KCE-TFD, which has 67,000 But/hr (19.6kW) cooling capacity at the AHRI high temperature air conditioning rating point when operated at 60 Hz. Note that the same compressor will have approximately 5/6 of this capacity or 55,000 Btu/hr (16.1kW) when operated at 50 Hz. Please refer to the on-line product information at
Emerson.com/OPI
for details.
APPLICATION CONSIDERATIONS
The following application guidelines shouldconsidered in the design of a system using ZP*K3, ZP*KC, and ZP*KW scroll compressors. Some of the guidelines are
recommended in this bulletin for good practice or best in class, other guidelines must be followed to ensure a safe and reliable application. The Application Engineering department always welcomes suggestions that will help improve these types of documents.
Internal Pressure Relief (IPR) Valve
The ZP91KC through ZP143KC compressors do not have IPR valves.
All other compressors in this family have an internal pressure relief valve which is located between the high and low side of the compressor. It is designed to open when the discharge-to-suction pressure differential exceeds 550 to 625 psid (38-43 bar). When the valve opens, hot discharge gas is routed back into the area of the motor overload to cause a trip. During fan failure testing, system behavior and operating pressures will depend on the type of refrigerant metering device. Fixed orifice devices may flood the compressor with refrigerant, and thermostatic expansion devices will attempt to control superheat and result in higher compressor top cap temperatures. Fan failure testing or loss of air flow in both cooling and heating should be evaluated by the system designer to assure that the compressor and system are protected from abnormally high pressures.
Discharge Temperature Protection
Compressor top cap temperatures can be very hot. Care must be taken to ensure that wiring or other materials which could be damaged by these temperatures do not come into contact with these potentially hot areas.
Protection against abnormally high discharge temperature is accomplished through one of the two folowing methods:
The Therm-O-Disc™ or TOD is a temperature-sensitive snap disc device located between the high and low pressure side of the scroll. It is designed to open and route excessively hot discharge gas back to the
Model
Application
IPR
Valve
Discharge Temp Protection
Internal
Overload
Electrical
Connections
AC
TOD
ASTP
ZP50-57K3
X
X X X X
MP, QC, TB
ZP61-83KC
X
X X X X
MP, QC, TB
ZP91KC
X
X
X X
MP, TB
ZP104-122KC
X
X
X X
MP, TB
ZP70-83KW
Pool Heating/Cooling
X X
X
MP, TB
ZP143KC
X
X
X X
MP, TB
© 2020 Emerson Climate Technologies, Inc.
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AE4-1365 R5
internal motor overload when the internal discharge gas exceeds 290°F (144°C). When the internal motor overload is subjected to hot discharge gas the overload will reach its opening temperature and take the compressor off-line. ZP91 and smaller compressors in this family use this method of temperature protection.
The second type of discharge temperature protection is referred to as Advanced Scroll Temperature Protection (ASTP). During a high discharge temperature event, a temperature-sensitive snap disk located in the intermediate cavity of the scroll will open and vent the intermediate cavity. This will result in the scrolls separating and not pumping. The motor will continue to run until the internal overload opens from a lack of refrigerant flow/cooling. The temperature-sensitive disk has a shorter reset time than the internal motor overload, so when the internal overload resets and brings the compressor back on line the compressor will run and pump. Compressors that have ASTP are identified with the ASTP label shown in
Figure 3
.
Heat Pump Protection
A low pressure control is highly recommended for loss of charge protection and other system fault conditions that may result in very low evaporating temperatures. Even though these compressors have internal discharge temperature protection, loss of system charge will result in overheating and recycling of the motor overload protector. Prolonged operation in this manner could result in oil pump out and eventual bearing failure. A cut out setting no lower than 20 psig (1.4 bar) is recommended.
Discharge Line Thermostat
Some systems, such as air-to-air heat pumps, may not work with the above low pressure control arrangement. A discharge line thermostat set to shut the compressor off before the discharge temperature exceeds 260°F (125°C) may have to be used to achieve the same protection. Mount the discharge thermostat as close as possible to the compressor discharge fitting and insulate well. See
Table 4
for recommended Emerson Climate
Technologies part numbers.
Air Conditioning Unit Protection
Air-conditioning-only units can be protected against high discharge temperatures through a low pressure control in the suction line. Testing has shown that a cut out setting of not lower than 55 psig (3.8 bar) will adequately protect the compressor against overheating from loss of charge, blower failure in a TXV system, etc. A higher level of protection is achieved if the low pressure control is set to cut out around 95 psig (6.7 bar) to prevent evaporator coil icing. The cut in setting can be as high as 180 psig (12.5 bar) to prevent rapid
recycling in case of refrigerant loss. If an electronic controller is used, the system can be locked out after repeated low pressure trips.
High Pressure Control
The ZP91KC through ZP143KC compressors do not have an internal pressure relief valve. A high pressure control with a maximum cut out setting of 650 psig (45 bar) is required for all ZP91KC through ZP143KC applications.
All other compressors in this family have an internal pressure relief valve and the necessity of a high pressure control switch is dependent on the working pressure of the system components. The high pressure control should have a manual reset feature for the highest level of system protection.
It is not recommended to use the compressor to test the high pressure switch function during the assembly line test.
Compressors requiring certification to the Pressure Equipment Directive (PED):
The nameplate will be marked with a TS min of -35°C where TS min is defined as the minimum allowable temperature. The nameplate will also be marked with a TS max of 150°C where TS max is defined as the maximum allowable temperature (°C, max design temperature, highest temp that can occur during operation or standstill of the refrigeration system or during test under test conditions, specified by the manufacturer). See
Table 5
for PED specific information. The nameplate will be marked with the internal free volume (IFV) of the compressor. The first two digits of the compressor serial number references the year of manufacture.
Discharge Check Valve
A low mass, disk type check valve in the discharge fitting of the compressor to prevent the high side, high pressure discharge gas from flowing rapidly back through the compressor after shutdown.
Motor Overload Protection
Conventional internal line break motor overload protection is provided. The overload protector opens the common connection of a single-phase motor and the center of the Y connection on three-phase motors. The three-phase overload protector provides primary single­phase protection. Both types of overload protectors react to current and motor winding temperature.
© 2020 Emerson Climate Technologies, Inc.
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AE4-1365 R5
Operating Envelope
The ZP model family is approved, and U.L. recognized, for use with R-410A only. See
Figures 1a and 1b
for the R-410A operating envelope. The envelope represents safe operating conditions with 20F° (11K) superheat in the return gas. Please note that the ZP*KW compressors have a smaller envelope for swimming pool applications.
Power Supply
All motors for the ZP compressors, whether single or three phase, with the exception of the “PFV” 208-230, 1Ø, 60 Hz motor, are designed to operate within a voltage range of +/-10% of the voltages shown on the nameplate. For example, a compressor with a nameplate voltage of 200-230 volts can start and operate within a range of 180-253 volts. Compressors with a “PFV” designated motor such as ZP50K3E-PFV, may only be operated in a range of 197-253 volts under maximum load conditions.
Accumulators
The use of accumulators is very dependent on the application. The Copeland Scroll compressor’s inherent ability to handle liquid refrigerant during occasional operating flood back situations make the use of an accumulator unnecessary in standard designs such as condensing units. Applications such as heat pumps with orifice refrigerant control that allow large volumes of liquid refrigerant to flood back to the compressor during normal steady-state operation can dilute the oil to such an extent that bearings are inadequately lubricated, and wear will occur. In such a case an accumulator must be used to reduce flood back to a safe level that the compressor can tolerate. Heat pumps designed with a TXV to control refrigerant during heating may not require an accumulator if testing assures the system designer that there will be no flood back throughout the operating range. To test for flood back conditions and determine if the accumulator or TXV design is adequate, please see the
Application Tests
section. The accumulator oil
return orifice should be from .040 to .055 inches (1 –
1.4mm) in diameter depending on compressor size and compressor flood back results. A large-area protective screen no finer than 30x30 mesh (0.6mm openings) is required to protect this small orifice from plugging. Tests have shown, that in the presence of very fine debris, a small screen with a fine mesh can easily become plugged causing oil starvation to the compressor bearings. The size of the accumulator depends upon the operating range of the system and the amount of sub cooling and subsequent head pressure allowed by the refrigerant control. System modeling indicates that heat pumps that operate down to and below 0°F (-18°C) will require an accumulator
that can hold around 70% to 75% of the system charge. Behavior of the accumulator and its ability to prevent liquid slugging and subsequent oil pump-out at the beginning and end of the defrost cycle should be assessed during system development. This will require special accumulators and compressors with sight tubes and/or sight glasses for monitoring refrigerant and oil levels.
Screens
Screens finer than 30x30 mesh (.06mm openings) should not be used anywhere in the system 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.
Crankcase Heat - Single Phase
A crankcase heater is
recommended
on single phase compressors when the system charge amount exceeds the limit shown in
Table 3
. A crankcase heater is
required
for systems containing more than 120% of
the compressor refrigerant charge limit listed in
Table
3
. This includes long line length systems where the extra charge will increase the standard factory charge above the 120% limit.
Experience has shown that compressors may fill with liquid refrigerant under certain circumstances and system configurations, notably after long off cycles when the compressor has cooled. This may cause excessive start-up clearing noise; or the compressor may start and trip the internal overload protector several times before running. The addition of a crankcase heater will reduce customer noise and dimming light complaints since the compressor will no longer have to clear out liquid during starting.
Table 4
lists the crankcase heaters recommended for the various models and voltages. voltages.
WARNING!
Crankcase heaters must be properly grounded.
The heater should be installed on the compressor shell as shown in
Figure 4
. Ideally the heater would come together for clamping with the vertical shell seam weld coming up through the area where the crankcase heater is clamped together. See
Figure 4
for details. Tighten the clamp screw carefully, ensuring that the heater is uniformly tensioned along its entire length and that the circumference of the heater element is in complete contact with the compressor shell. It's important that the clamp screw is torqued to the range of 20-25 in-lb (2.3-8 N m) to ensure adequate contact and to prevent heater burnout. Never apply power to a heater in free air or before the heater is installed on the
© 2020 Emerson Climate Technologies, Inc.
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AE4-1365 R5
compressor to prevent overheating and burnout.
Crankcase Heat - Three Phase
A crankcase heater is
required
for three-phase compressors when the system charge amount exceeds the compressor charge limit listed in
Table 3. Pump Down Cycle
A pump down cycle for control of refrigerant migration is not recommended for scroll compressors of this size.
If a pump down cycle is used, a separate discharge line check valve must be added.
The scroll compressor’s 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.
Minimum Run Time
There is no set answer to how often scroll compressors can be started and stopped in an hour, since it is highly dependent on system configuration. Other than the considerations in the section on
Brief
Power Interruptions
, there is no minimum off time because Copeland Scroll compressors start unloaded, even if the system has unbalanced pressures. The most critical consideration is the minimum run time required to return oil to the compressor after startup. To establish the minimum run time, obtain a sample compressor equipped with a sight tube (available from Emerson) 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 startup to return to the compressor sump and restore a minimal oil level that will assure oil pick up 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. See
AE17-1262
for more information on
preventing compressor short cycling.
Reversing Valves
Since Copeland Scroll compressors have very high volumetric efficiency, their displacements are lower than those of comparable capacity reciprocating compressors.
CAUTION Reversing valve sizing must be within the guidelines of the valve manufacturer. Required pressure drop to ensure valve shifting must be measured throughout the operating range of the unit and compared to the valve manufacturer's data. Low ambient heating conditions with low flow rates and low pressure drop across the valve can result in a valve not shifting. This can result in a condition where the compressor appears to be not pumping (i.e. balanced pressures). It can also result in elevated compressor sound levels.
During a defrost cycle,
when the reversing valve abruptly changes the refrigerant flow direction, the suction and discharge pressures will go outside of the normal operating envelope. The sound that the compressor makes during this transition period is normal, and the duration of the sound will depend on the coil volume, outdoor ambient, and system charge. The preferred method of mitigating defrost sound is to shut down the compressor for 20 to 30 seconds when the reversing valve changes position going into and coming out of the defrost cycle. This technique allows the system pressures to reach equilibrium without the compressor running. The additional start-stop cycles do not exceed the compressor design limits, but suction and discharge tubing design should be evaluated.
The reversing valve solenoid should be wired so that the valve does not reverse when the system is shut off by the operating thermostat in the heating or cooling mode. If the valve is allowed to reverse at system shutoff, suction and discharge pressures are reversed to the compressor. This results in pressures equalizing through the compressor which can cause the compressor to slowly rotate backwards until the pressures equalize. This condition does not affect compressor durability but can cause unexpected sound after the compressor is turned off.
Low Ambient Cut-Out
Because of internal discharge temperature protection, a low ambient cut-out is not required to limit air-to air heat pump operation. Air-to-water heat pumps must be reviewed since this configuration could possibly run outside of the approved operating envelope (
Figure 1
)
causing overheating or excessive wear.
Oil Type
POE may cause an allergic skin reaction and must be handled carefully and the proper protective equipment (gloves, eye protection, etc.) must be used when handling POE lubricant. POE must not come into contact with any surface or material that might be harmed by POE, including without limitation, certain polymers (e.g. PVC/ CPVC and polycarbonate). Refer to the Safety Data Sheet (SDS) for further details.).
Polyol ester (POE) oil is used in these compressors. See the compressor nameplate for the original oil charge. A complete recharge should be approximately four fluid ounces (118 ml) less than the nameplate value. Copeland™ Ultra 32-3MAF, available from Emerson Wholesalers, should be used if additional oil is needed in the field. Mobil Arctic EAL22CC,
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