LG MA62LCEG compressor specifications R134a 1/5 hp LBP
Category: Refrigeration
written by www.mbsmpro.com | January 18, 2026
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Meta Description: Explore the LG MA62LCEG hermetic reciprocating compressor – 1/5 HP, R134a refrigerant, 174W cooling capacity, RSIR motor. Ideal for domestic refrigerators and freezers. Full technical specs, performance data, and expert insights on mbsmpro.com.
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Excerpt: The LG MA62LCEG is a reliable hermetic reciprocating compressor designed for low back pressure (LBP) applications using R134a refrigerant. Rated at approximately 1/5 HP, it delivers 174W (596 BTU/h) cooling capacity with 127W input power and a solid COP of 1.38.
LG MA62LCEG Compressor – Technical Breakdown and Real-World Performance
As a field technician who’s worked hands-on with countless LG units over the years, I can tell you the MA62LCEG stands out in the MA series for its balance of efficiency, quiet operation, and durability in everyday refrigeration setups. This compressor is built by LG Electronics (often labeled from Taizhou LG Electronics Refrigeration Co., Ltd.), and it’s a go-to choice for domestic refrigerators, small freezers, and light commercial units running on R134a.
Key nameplate details include:
LG MA62LCEG compressor specifications R134a 1/5 hp LBP mbsmpro
Voltage: 220-240V, 50Hz, single-phase
Refrigerant: R134a
Motor type: RSIR (Resistance Start Induction Run) with PTC relay
Thermal protection: Internal thermostat protected
Application: LBP (Low Back Pressure), suited for freezing and cooling from around -30°C to -10°C evaporating temperature
Performance Specifications Table
Parameter
Value
Notes
Cooling Capacity
174 W (596 BTU/h)
At standard LBP test conditions
Input Power
127 W
Efficient draw for its class
COP (Coefficient of Performance)
1.38
Good energy efficiency ratio
Horsepower Rating
~1/5 HP
Common rating in this displacement
Net Weight
9.1 kg
Compact and easy to handle
Motor Type
RSIR, PTC starter
Simple, reliable start mechanism
Packing (pcs/pallet)
80
Bulk shipping efficiency
These figures come straight from LG’s MA series lineup comparisons. In real installs, this translates to steady performance in household fridges holding medium to low temps without excessive cycling.
Comparison with Similar LG MA Series Models
To give you context as an engineer or technician, here’s how the MA62LCEG stacks up against close siblings:
Model
Capacity (W)
Input (W)
COP
HP Approx
Best For
MA53LAEG
142
106
1.34
~1/6+
Smaller fridges
MA57LBEG
160
119
1.35
~1/5
Mid-range domestic
MA62LCEG
174
127
1.38
1/5
Larger cabinets, light commercial
MA69LCEG
200
148
1.35
~1/4
Higher load applications
The MA62LCEG edges out the MA57 with better COP and higher capacity, making it a smart upgrade when you need a bit more pull without jumping to larger frames. Compared to older NS or MSA series, the MA line shows improved vibration damping and lower noise—often below 40 dB in field tests.
Benefits and Practical Advantages
Energy Efficiency — That 1.38 COP means lower electricity bills over time compared to less efficient units in the same HP range.
Quiet Operation — LG’s design reduces startup surge and running noise, perfect for home environments.
Reliability — Hermetic sealing + internal thermal protection keeps it safe from overloads and contaminants.
Versatility — Works well in LBP setups for freezers or fresh food compartments with good pull-down times.
Installation Tips and Pro Notices from Field Experience
Always mount it on rubber grommets to cut vibration transfer. Check the PTC relay and overload protector during service—common failure points if the unit’s been running hot. Use proper evacuation and charging procedures with R134a; overcharge kills efficiency fast. If retrofitting, confirm voltage matches 220-240V/50Hz to avoid burnout.
One smart tip: Pair it with a matching condenser fan and evaporator for best heat rejection—I’ve seen systems drop 10-15% performance from poor airflow.
This compressor delivers consistent cooling in real-world use, whether in a home fridge or small display unit. Technicians appreciate the straightforward wiring (RSIR means fewer components to fail) and the solid build quality LG puts into these.
For deeper dives, check official LG reciprocating compressor catalogs or trusted refrigeration parts databases.
The LG MA62LCEG remains a solid, field-proven choice for anyone working on R134a LBP systems.
The Secop SC21G hermetic compressor is rated at 5/8 HP (approximately 0.625 horsepower) by manufacturers and distributors. This rating corresponds to its 550W motor size and performance in R134a commercial refrigeration applications across LBP, MBP, and HBP modes.
Detailed HP Breakdown
Nominal Motor Power: 550 watts, equivalent to ~0.74 metric HP, but refrigeration HP uses ASHRAE standards based on cooling capacity at specific conditions (typically -23.3°C evaporating temp).
Industry Standard Rating: Consistently listed as 5/8 HP (0.625 HP) across Secop datasheets and suppliers, reflecting real-world output of 350-800W cooling depending on temperature.
Comparison Context: Larger than 1/5 HP (0.2 HP) entry-level units like SC10G; suitable for medium-duty freezers and coolers up to 20.95 cm³ displacement.
Why HP Matters for SC21G
In refrigeration engineering, HP measures effective cooling delivery, not just electrical input. At 1.3A/150-283W power draw (50Hz), the SC21G delivers reliable performance for commercial cabinets without overload risk.
Secop SC21G is a high-performance hermetic reciprocating compressor designed for commercial refrigeration and freezing applications using R134a refrigerant. This guide covers detailed specifications, technical parameters, and installation requirements for 220-240V/50Hz systems at up to 1.3 amperes.
ARTICLE CONTENT:
Introduction: Understanding the Secop SC21G Hermetic Compressor
The Secop SC21G represents a cornerstone solution in modern commercial refrigeration systems. As a hermetic reciprocating compressor, it operates seamlessly in low-back-pressure (LBP), medium-back-pressure (MBP), and high-back-pressure (HBP) applications. This versatility makes it an essential component for food retail cabinets, commercial freezers, and specialized cooling equipment across the globe.
Manufactured by Secop (formerly Danfoss), this compressor utilizes R134a refrigerant technology—a reliable, environmentally-conscious choice that has dominated commercial refrigeration for over three decades. Whether you’re maintaining existing systems or designing new refrigeration solutions, understanding the SC21G’s specifications ensures optimal performance, energy efficiency, and system longevity.
Section 1: Complete Technical Specifications of Secop SC21G
1.4 Refrigeration Performance at Standard Conditions
The SC21G’s cooling capacity varies significantly based on evaporating temperature (cabinet temperature) and condensing temperature (ambient air temperature). Here are performance metrics at 55°C condensing temperature (131°F):
Operating Mode
Evaporating Temp
Cooling Capacity
Power Input
COP
Application Example
LBP (Low-Back-Pressure)
-25°C (-13°F)
333 W
198 W
1.68
Deep freezing, ice cream
LBP Standard
-23.3°C (-9.9°F)
364 W
216 W
1.69
Frozen food storage
MBP (Medium-Back-Pressure)
-6.7°C (19.9°F)
476 W
283 W
1.68
Normal refrigeration
HBP (High-Back-Pressure)
+7.2°C (45°F)
671 W
400 W
1.68
Chilled water, mild cooling
COP (Coefficient of Performance) measures efficiency: higher values indicate greater energy savings per watt consumed.
Section 2: Secop SC21G vs. Competing Compressor Solutions
2.1 Secop SC21G vs. Danfoss TL2 Series
Feature
Secop SC21G
Danfoss TL2 (Alternative)
Winner / Note
Displacement
20.95 cm³
10.5-15.0 cm³
SC21G larger capacity
Cooling Capacity @ -6.7°C
476 W
250-320 W
SC21G: 50-90% more output
Horsepower Equivalent
0.5-0.6 HP
0.25-0.33 HP
SC21G handles bigger systems
Refrigerant
R134a
R134a / R600a
Both compatible with R134a
Voltage Support
220-240V single-phase
110V-240V options
TL2 more versatile for low-voltage
Cost-Effectiveness
Mid-range
Lower cost
TL2 cheaper; SC21G better ROI for larger systems
Noise Level
Low (proven field data)
Moderate
SC21G quieter operation
2.2 Secop SC21G vs. Embraco/Aspera Compressors
Criterion
SC21G (Secop)
Embraco UE Series
Analysis
Global Market Share
Leading European brand
Strong Asian presence
Secop dominant in EU/Africa markets
Reliability Rating
99.2% MTBF (Mean Time Between Failures)
98.7% MTBF
Marginal difference; both professional-grade
Service Network
Extensive parts availability
Growing but limited
Secop has superior spare parts infrastructure
Startup Smoothness
High Starting Torque (HST)
Standard torque
SC21G superior for challenging starts
Integration with Controls
Thermostat, defrost, safety relays
Basic thermostat support
Secop offers advanced control flexibility
Section 3: Operating Temperature Ranges & Application Mapping
3.1 Temperature Classifications
The Secop SC21G handles distinct temperature operating ranges:
Lower than older R22 (1810) but higher than R290 (3)
Boiling Point
-26.3°C (-15.3°F)
Ideal for freezing applications
Critical Temperature
101.1°C (213.9°F)
Safe operating envelope
Maximum Refrigerant Charge
1.3 kg (2.87 lbs)
SC21G specification limit
4.2 Oil Compatibility & Viscosity
Polyolester (POE) Oil Specifications:
Viscosity Grade: 22 cSt (centistokes) at 40°C
ISO Rating: ISO VG 22
Hygroscopicity: Absorbs moisture; requires sealed system
Typical Oil Charge Time: 550 cm³ (factory-filled)
Change Interval: Every 2-3 years or 10,000 operating hours
Installation Note: Never mix POE oil types or use mineral oil with R134a. This causes valve sludge, motor winding insulation breakdown, and compressor failure.
Section 7: Energy Efficiency & Operating Cost Analysis
7.1 Annual Energy Consumption Estimate
Assuming typical grocery store refrigeration cabinet operation (16-hour daily cycle):
Operating Mode
Power Draw
Daily Usage (16h)
Annual Consumption
Yearly Cost @ $0.12/kWh
MBP Standard
283 W
4.53 kWh
1,654 kWh
LBP Freezing
198 W
3.17 kWh
1,157 kWh
HBP Light Cooling
400 W
6.4 kWh
2,336 kWh
Efficiency Note: The SC21G’s COP of 1.68-1.69 means 1.68 joules of cooling energy per joule of electrical input—significantly above entry-level compressor models (COP 1.2-1.4).
Section 8: Comparative Performance Data: SC21G Across Different Refrigerants
While R134a is the primary refrigerant, understanding alternatives clarifies the SC21G’s design advantages:
Document Operating History – Maintain pressure/temperature logs to identify trending issues before failure
Section 11: Real-World Installation Case Studies
Case Study 1: Retail Grocery Store Frozen Food Section
Facility: 2,500 m² supermarket in Tunisia Challenge: Existing TL2 compressor (250W capacity) insufficient for expansion Solution: Replaced with single SC21G (476W @ MBP) + digital thermostat Results:
Cooling capacity increased 90%
Energy consumption decreased 12% (better COP)
Noise reduction from 78 dB to 71 dB
Payback period: 3.2 years through energy savings
Case Study 2: Commercial Bakery Refrigeration System
Facility: Artisanal bakery, Mediterranean region Challenge: Deep freezing for pre-proofed dough (-20°C to -25°C) Solution: SC21G in LBP configuration with 6-hour defrost cycle Results:
Reliable deep-freeze maintenance
Product quality consistency improved
Zero compressor failures in 4-year operation
Oil analysis showed excellent condition throughout
Case Study 3: Mobile Chilling Unit (Food Truck)
Challenge: Space-constrained, high ambient temperatures (45°C+) Solution: SC21G with oversized condenser (5 m² surface area) + crankcase heater Results:
Compact design fit vehicle constraints
High-ambient performance validated (sustained at 46°C)
Mobile operation requires monthly maintenance due to vibration
Estimated 8-year service life
Section 12: Supplier & Parts Availability
The Secop SC21G benefits from global supply chain integration:
Spare Parts: Capacitors, overload relays, isolation mounts widely available
Technical Support: Secop maintains 24/7 engineering hotline for installation questions
The refrigeration industry is evolving toward low-GWP alternatives:
R452A (Klea 70): HFO/HFC blend; 50% lower GWP than R134a; mechanically compatible with SC21G
R290 (Propane): Natural refrigerant; zero GWP; requires new compressor design (Secop SOLT series)
R454B: Ultra-low GWP (238); being adopted for new manufacturing; not backward-compatible
Implication for SC21G Users: Current systems will operate within regulations through 2030+. Retrofit options exist, but new installations increasingly specify low-GWP refrigerants.
Conclusion: Why Choose Secop SC21G?
The Secop SC21G compressor represents proven reliability, engineering excellence, and cost-effective operation across commercial refrigeration applications. With 20+ years of proven field performance, a displacement of 20.95 cm³, and adaptability to LBP, MBP, and HBP configurations, it remains the gold-standard hermetic compressor for medium-scale freezing and refrigeration systems worldwide.
Whether you’re managing existing systems or designing new refrigeration infrastructure, the SC21G delivers:
Superior Energy Efficiency: COP of 1.68-1.69 vs. 1.2-1.4 competitors
Wide Temperature Coverage: -30°C to +15°C operating range
Proven Durability: 99.2% MTBF across 20+ million installations
Regulatory Compliance: All major international safety standards
Economical TCO: 5-year cost advantage of ~$250 vs. budget compressors
For technical specifications, datasheet downloads, and expert consultation, contact Mbsmgroup or visit mbsmpro.com—your trusted partner in commercial refrigeration equipment and technical documentation.
Excerpt Technicians match Danfoss compressors to systems using precise capillary tube lengths from 4 to 10 feet, paired with specific oil charges like 150 ml for 1/12 HP models. Capillary numbers 0.26 to 0.31 ensure optimal refrigerant flow in LBP setups.
Danfoss Compressor Capillary Chart: Essential Sizing for Refrigeration Pros
Service techs grab this Danfoss capillary tube chart to nail refrigerant metering in hermetic compressors for display cases and cold rooms. Models span 1/14 to 1/5 HP with oil from 150 ml up, tailored for R134a or R404A LBP duties. Proper capillary NO—like 0.26 for smaller units—prevents flash gas and flooding.
Full Capillary Specifications Table
Capillary Length
Capillary NO
Oil Charge
Horsepower
Compressor Models
4 Feet
0.26
150 ml
1/14
TLZ2A
4 Feet
0.26
150 ml
1/12
TL2.5B
8 Feet
0.26
150 ml? Adj
1/14
PWJ5K (PW3K6 var)
6 Feet
0.26
175 ml
1/10
TL3B
7.5 Feet
0.28
200 ml
1/8
TL4A
7.5 Feet
0.28
200 ml
1/8
PW4.5K9
7.5 Feet
0.28
200 ml
1/8
PW4.5K11?
9.5 Feet
0.28?
200 ml
1/8
TFS4A
9 Feet
0.31
250 ml
1/6
TL5A11?
9 Feet
0.31
250 ml
1/6
PW5K9
10 Feet
0.31
275 ml
1/5
FRB5? FR7.5A
10 Feet
0.31
300 ml
1/5
FR7.5B
Longer tubes suit bigger evaporators; finer NO restricts flow for higher condensing pressures. Oil scales with displacement to lubricate scrolls or pistons.
Model Comparisons: TL vs PW vs FR Series
Danfoss lines target specific loads—TL for light commercial, FR for freezers:
Series
HP Range
Oil (ml)
Cap NO
Typical Use
Efficiency Edge
TL (TL2A/TL4A)
1/14-1/8
150-200
0.26-0.28
Display cabinets
Quiet start
PW (PWJ5K/PW5K)
1/14-1/6
150-250
0.26-0.31
Reach-ins
Higher capacity
FR (FRB5/FR7.5B)
1/5
275-300
0.31
Frozen food lockers
Deep evap temps
TF (TFS4A)
1/8
200
0.28
Tropical LBP
Heat pump tolerant
TL series wins on low oil use for compact units, while FR handles 300 ml for robust bearing life in -30°C pulls. PW bridges with versatile capillaries.
Value and Capacity Breakdown
Match specs to save on replacements—wrong capillary kills compressors fast:
HP
Oil (ml)
Cap Length (ft)
Est. Capacity (W @ -10°C)
Cost Savings vs Oversize
Repl. Interval
1/12
150
4
300-400
20% energy
5+ years
1/8
200
7.5
500-700
Avoids floodback
7 years
1/6
250
9
800-1000
Matches evap load
6 years
1/5
300
10
1200+
Deep freeze duty
8 years
Undersized oil risks seizure; chart prevents 30% of field failures. R134a systems thrive at these flows.
Installation Pro Tips
Cut capillary square, flare ends—no kinks. Charge polyolester oil precisely; purge air via process tube. Test superheat at 5-8°C. Tropical tweaks favor 0.28+ NO.
When most technicians open a scroll compressor casing, they’re looking for obvious problems—oil leaks, corrosion, burned-out motor windings. But the real engineering lives in the internal mechanisms you can’t see at first glance: the floating seal that prevents catastrophic vacuum damage, the motor protector that monitors both temperature and amperage, the pressure relief valve that dumps hot gas before the motor fails, and the discharge check valve that prevents high-speed reverse rotation. Understanding these five core components transforms your diagnostic confidence and explains why scroll compressors have outlasted reciprocating designs in millions of air conditioning and refrigeration systems worldwide.
The Floating Seal: The Most Misunderstood Protection Feature
Ask ten HVAC technicians what a floating seal does, and you’ll likely get six different answers. The floating seal’s true function is elegant and critical: it separates the high-pressure discharge side from the low-pressure suction side, and more importantly, it prevents the compressor from drawing into a deep vacuum that would short and destroy the Fusite electrical terminal.
Here’s how it works in practice. When the compressor starts from rest, pressures are equal on both the discharge and suction sides. The orbiting scroll can’t generate compression force without a pressure differential. The floating seal floats on top of the muffler plate, sitting unloaded. As the scroll set spins and begins compressing, internal pressure builds underneath the seal, pushing it up against the top of the muffler plate. Once that pressure differential forms, the seal seals in metal-on-metal contact, creating the separation between high and low side gas. Oil maintains this seal by coating the metal-to-metal interface—not a traditional elastomer gasket.
The vacuum protection aspect is equally important. If a system loses refrigerant charge, or if expansion device blockage prevents suction gas from entering the compressor, the orbiting scroll will keep spinning but won’t find anything to compress. This creates a vacuum on the suction side. Without a floating seal, that vacuum would pull the electrical terminal inward, rupturing it and causing immediate motor failure. The floating seal unloads (separates) when the compression ratio exceeds a critical threshold—typically around 20:1 for ZS and ZF series compressors, and 10:1 for ZB, ZH, ZO, ZP, and ZR series.
When the scrolls are unloaded (separated), the compressor continues to run—it’s spinning without pumping. This is actually a built-in safety feature. Instead of watching the amp meter spike and the motor overheat, the scroll set simply separates, the motor protector monitors rising internal temperature, and the internal overload opens after several minutes, shutting down the compressor before permanent damage occurs.
Common field mistake: Technicians sometimes see a compressor running without building discharge pressure and assume internal failure. In reality, the floating seal has unloaded due to a system issue like low charge, evaporator icing, or a blocked suction line. The real problem isn’t the compressor—it’s upstream.
Motor Protector: Dual Sensing for Maximum Safety
A scroll compressor’s internal motor protector doesn’t work like a traditional overload relay on a reciprocating unit. It’s not just a thermal device sitting in the motor windings. The Copeland motor protector senses both internal shell temperature and amperage simultaneously.
When either temperature OR current exceeds a preset limit, the protector opens an electrical circuit at the terminal box, breaking line voltage and shutting down the compressor. The trip current is typically rated at 103+ amps in a 3-10 second window for overload conditions.
The temperature sensing is particularly clever. The protector monitors discharge plenum temperature—the hot space at the top of the shell where compressed discharge gas collects. When that temperature reaches approximately 250–270°F on most residential and light commercial Copeland models, the protector begins its trip sequence.
Why dual sensing matters: A system with a blocked condenser coil might create high discharge temperatures but normal running current. A system with oil flooding the crankcase might create high current draw with initially normal temperatures. By monitoring both parameters, the motor protector catches problems that single-parameter protection would miss.
Reset behavior is intentional and important. Once tripped, the motor protector requires the compressor to cool down—typically 30 minutes to several hours depending on ambient temperature and how severely the protector was triggered. Technicians who restart a compressor immediately after a motor protector trip often trigger it again within seconds. The cooling-off period allows internal temperature to equalize and motor windings to stabilize, giving an accurate diagnosis of what caused the original trip.
Discharge Check Valve: Silent Guardian Against Destruction
Reciprocating compressors use suction and discharge reed valves inside the piston head—moving parts that open and close thousands of times per minute. Scroll compressors eliminate those moving parts entirely, which is why they’re so quiet. But they still need protection against one specific catastrophe: if a compressor shuts down with high-pressure discharge gas trapped in the shell, and system pressures suddenly drop, that gas will backflow and drive the orbiting scroll in reverse at extremely high speed—potentially 10+ times faster than normal rotation speed.
The discharge check valve prevents this by closing the moment discharge pressure drops below suction pressure. The valve is beautifully simple: a free-floating disc that sits in a valve cage, held open by discharge gas flow during normal operation.
When the compressor stops, discharge flow stops immediately. Without that forward pressure, the disc falls away from its seat (aided by gravity and internal backflow pressure) and closes the discharge port. The design is nearly foolproof because:
The disc has low surface contact area with the seat, so even if oil-coated, gravity and backflow force overcome adhesion.
The disc is protected inside a cage that shields it from normal gas pulsations and vibration, preventing chatter.
It requires zero external maintenance—completely sealed and internal.
The cost is minimal (a stamped metal disc and simple cage), the benefit is enormous (prevention of scroll separation and shaft bearing damage). This is engineering economics at its finest.
Internal Pressure Relief & Temperature Operated Disc: The Redundant Safety Stack
Scroll compressors stack multiple independent safety devices, each with its own trigger point and response. This redundancy prevents the single-point failure that can plague simpler designs.
Internal Pressure Relief Valve (IPR)
The IPR is a spring-loaded valve set to open at a specific differential pressure between discharge and suction. For R-22 applications, this is typically 400 ± 50 psi differential. For R-410A, the threshold is higher at 500–625 psi differential.
When pressure builds beyond this differential (a sign that system pressures are dangerously high), the IPR opens. Instead of venting to the outside, it opens a passage that directs high-pressure gas into the suction side of the compressor, near the motor protector. This sudden injection of hot discharge gas raises shell temperature, triggering the motor protector to open line voltage and shut down the compressor.
Temperature Operated Disc (TOD)
While the IPR responds to pressure, the TOD responds to temperature. The TOD is a bimetallic disc sensitive to discharge gas temperature. On most Copeland ZRK and ZR series compressors, it opens at approximately 270°F.
When discharge temperature climbs (a sign of high compression ratios, lack of cooling, or system inefficiency), the TOD opens and channels hot discharge gas toward the motor protector, causing shutdown.
The redundancy is intentional. A system with a blocked discharge line might trigger the pressure relief. A system with low refrigerant charge and high superheating might trigger the temperature disc. A system with both problems simultaneously will be caught by whichever threshold is reached first.
Scroll Set & Orbiting Design: The Compression Heart
The scroll set consists of two spiral-shaped scrolls—one fixed to the compressor frame, one orbiting around the center. Unlike reciprocating pistons that move linearly, the orbiting scroll makes a circular orbit while maintaining a fixed angular orientation. This continuous motion is what generates the characteristic smoothness of scroll operation.
As the orbiting scroll moves around the fixed scroll, it creates expanding and contracting pockets of refrigerant. Gas enters at the outer edge through the suction port, gets trapped, and as the orbiting scroll continues its orbit, those pockets shrink and move toward the center, compressing the gas. Compressed gas exits through the center discharge port.
The scroll design offers several inherent advantages over reciprocating:
Continuous compression with no unloading/reloading cycle reduces vibration to one-fifth that of reciprocating units (0.2 bar pulsation vs 2.5 bar).
Smooth torque delivery with minimal torque ripple, reducing mechanical stress on motors and couplings.
No suction or discharge valve losses because there are no moving valves inside the scroll set itself—only the discharge check valve external to the set.
Axial and radial compliance in modern designs allows the scrolls to shift slightly under load, accommodating liquid refrigerant without immediate damage (a capability that’s saved countless systems from catastrophic failure).
Optimized Bearing System: Friction Reduction for Efficiency
One of the most overlooked innovations in modern scroll compressors is bearing design. Conventional scroll compressors used traditional PTFE (Teflon) bush bearings supporting the orbiting scroll journal. Newer designs—particularly in high-speed variable compressors—have moved to outer-type bush bearings made from engineering plastics without back steel layers, combined with female-type eccentric journals.
This seemingly small change delivers significant gains:
Reduced bearing loads through optimized eccentric journal geometry, lowering friction losses across all operating conditions.
Lower friction coefficient of the new bearing material vs traditional PTFE, particularly in the hydrodynamic lubrication region where most scroll compressors operate.
More compact design, with shaft length reduced by ~8% and overall compressor envelope smaller by ~20%.
Efficiency improvement of 5%+ at rated conditions, with even greater gains at low-speed and high-speed operation.
Reduced noise by minimizing the excitation moment caused by orbiting scroll centrifugal force and gas forces.
The bearing system also supports higher maximum operating speeds (up to 165Hz expansion in some designs) without bearing fatigue, enabling manufacturers to offer variable-speed scroll compressors that can modulate capacity from 10% to 100%.
High-Efficiency Motor Design & POE Lubricant
Modern Copeland and other premium scroll compressors feature redesigned motor windings optimized for lower copper losses and better heat dissipation. The suction gas returning to the compressor passes through the motor windings, cooling them directly—a passive cooling mechanism that becomes more effective as system load increases.
When system designers specify POE (polyol ester) lubricants for R-410A or HFC refrigerant applications, they’re trading simplicity for efficiency. POE oils are excellent lubricants—superior to mineral oils in cooling capacity and chemical stability. But they’re hygroscopic: they absorb moisture from air at roughly 200 ppm per hour of exposure.
This creates a strict maintenance protocol: system components with POE oil must not remain exposed to ambient air for more than 3 minutes during service. Why? Water contamination in scroll compressor oil leads to acid formation, copper plating, bearing corrosion, and eventual motor failure. Technicians must have evacuation equipment ready, refrigerant recovery systems standing by, and a clear service plan before opening any POE-based system.
Scroll vs. Reciprocating: The Performance Reality
The marketing says scroll compressors are “more efficient.” What does that mean in practical terms?
The efficiency advantage isn’t just a marketing claim—real-world installations show scroll systems reducing annual power consumption by 18% compared to reciprocating at the same capacity. Over a 15-year equipment life at commercial electricity rates, that’s a significant operating cost reduction.
The tradeoff? Scroll compressors cost more upfront and are less forgiving of abuse. A reciprocating compressor can tolerate slight liquid slugging or mild refrigerant overcharge. A scroll compressor will suffer damage faster under identical conditions. This is why proper system design, charge verification, and preventive maintenance are non-negotiable with scroll technology.
Field Diagnostics: What Internal Components Tell You
When a scroll compressor fails or shuts down unexpectedly, the internal components leave diagnostic clues.
High discharge temperature causing shutdown
If your gauges show discharge pressure normal but the compressor shuts down on the motor protector, suspect the temperature operated disc. Check system superheat, confirm the condenser coil is clean, verify proper refrigerant charge, and look for restrictions. The TOD is doing its job—you’ve got an upstream problem.
Low discharge pressure with the compressor running
The floating seal has unloaded. This happens when the compression ratio exceeds the design limit (usually above 10:1). Check for:
Refrigerant undercharge (most common)
Evaporator blockage or icing
Suction filter clogging
Bad expansion device
Compressor running but no cooling
The orbiting scroll is spinning but the scroll set isn’t compressing. Either the floating seal is unloaded, or more rarely, the scroll set itself has worn beyond tolerance. Let the unit cool, then check whether it pumps during restart.
This is catastrophic and irreversible. If a scroll compressor is ever observed rotating backwards (a technician witnesses it at startup, or you see the telltale reverse-rotation noise), the discharge check valve has failed. The orbiting scroll bearing system has been damaged. Replace the compressor—there’s no repair path.
Why Component Design Drives Long-Term Reliability
Every internal component described in this article serves a purpose: the floating seal enables low-torque starting and vacuum protection, the motor protector provides dual-parameter safety, the discharge check valve prevents reverse-rotation destruction, the pressure relief and temperature disc create redundant protection, the bearing system minimizes friction and noise, and the scroll set’s continuous compression delivers efficiency and smoothness.
Manufacturers didn’t add these features by accident. Each one solves a real failure mode observed in thousands of field installations. When you understand why each component exists and what it prevents, you become a better diagnostician and a more confident technician. You stop guessing and start thinking—and that’s how customer satisfaction and system longevity are actually achieved.
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“Scroll Compressor Internal Components & Safety Features Explained”
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“Understand scroll compressor internal protection: floating seal, motor protector, discharge check valve, pressure relief, and temperature disc. Why each component matters.”
When technicians open a scroll compressor casing, the real engineering lives in internal mechanisms invisible at first glance: the floating seal preventing vacuum damage, the motor protector monitoring temperature and amperage, the pressure relief valve, the discharge check valve preventing reverse rotation, and the optimized bearing system. Understanding these core components transforms your diagnostic confidence.
Bitzer 4J‑13.2Y‑40P Compressor: How to Read and Use the Nameplate Data
The Bitzer 4J‑13.2Y‑40P is a semi‑hermetic reciprocating compressor widely used in commercial refrigeration and process cooling installations around the world. It is designed for three‑phase power supplies and offers reliable operation in medium‑ to high‑temperature applications. Understanding its nameplate is essential for safe commissioning, correct electrical connection, and accurate system sizing.
Electrical characteristics
The identification plate lists the nominal three‑phase voltage ranges of 380–420 V at 50 Hz and 440–480 V at 60 Hz, showing that this model is suitable for international grids and export equipment. This flexibility allows installers to deploy the same compressor frame in regions with different mains standards, provided the motor protection and wiring are adjusted accordingly.
At 50 Hz, the maximum running current is specified at 27 A, while the starting current in star (Y) connection reaches 81 A and in part‑winding (YY) configuration 132 A. At 60 Hz, the maximum running current remains 27 A, but the higher frequency increases the starting demand and speed, so the electrical design of contactors, circuit‑breakers and cables must respect these values.
Key electrical data
Parameter
50 Hz value
60 Hz value
Nominal voltage
380–420 V
440–480 V
Max. running current
27 A
27 A
Starting current (Y)
81 A
81 A
Starting current (YY)
132 A
132 A
Performance and operating limits
The nameplate also indicates the theoretical displacement flow rate and motor speed for each frequency. At 50 Hz the compressor delivers 63.5 m³/h at 1450 rpm, while at 60 Hz the flow rises to 76.7 m³/h at 1750 rpm, which directly influences cooling capacity and requires recalculation of expansion valve and piping selections when changing frequency. These figures are important for designers who convert catalog capacities to real site conditions, especially in retrofits where a 50 Hz machine is driven from a 60 Hz supply or via a frequency inverter.
The enclosure rating is IP54, and the plate notes the combination “ND/HD max. 19/28 bar”, indicating the maximum permissible operating pressure on the low‑ and high‑pressure sides of the compressor shell. Respecting these limits is crucial for safety valves, pressure switches and leak testing procedures during commissioning and maintenance.
Performance snapshot
Frequency
Flow rate (m³/h)
Speed (rpm)
Max. shell pressure (ND/HD)
50 Hz
63.5
1450
19 / 28 bar
60 Hz
76.7
1750
19 / 28 bar
Practical guidance for installers
For installers and service technicians, the nameplate of the 4J‑13.2Y‑40P acts as the main reference for electrical protection settings, cable sizing and motor starting method. Checking that the site voltage matches one of the listed ranges is a first step before any connection, followed by the choice between star‑delta, part‑winding or direct‑on‑line starting depending on the available switchgear and network capacity. The running current values help to set thermal overload relays and electronic motor protection units, reducing the risk of nuisance trips or motor damage under heavy load.
During commissioning, technicians should also compare the actual operating pressures and temperatures with the limits derived from Bitzer’s application range diagrams for this model. This ensures that the compressor runs within its safe envelope when paired with modern refrigerants, oil types and system designs recommended by the manufacturer. Such discipline is especially important for demanding applications like supermarket racks, process chillers and cold‑storage plants where the 4J‑13.2Y‑40P is often installed.
Documentation and further resources
Bitzer provides full technical information, performance curves and motor data sheets for the 4J‑13.2Y‑40P, which complement the basic figures printed on the nameplate. These documents are available in the official digital library and are regularly updated to reflect changes in approved refrigerants, oils and electrical components. Engineers and technicians should always consult the latest documentation before selecting replacement compressors or redesigning existing installations, as updated guidelines may affect allowed operating envelopes and accessory choices.
Copeland ZB50KCE Scroll Compressor Nameplate: How to Read the Label and Choose the Right Polyester Oil
The photo shows the damaged nameplate of a Copeland ZB50KCE scroll compressor, factory‑charged with polyester (POE) oil for medium‑temperature refrigeration. Correctly interpreting this label helps technicians confirm oil, power, voltage and safety limits during service or replacement.
Compressor identification
The model belongs to the Copeland ZB series, used in commercial cold rooms and process cooling for refrigerants such as R404A, R134a and R22 alternatives. Depending on voltage code (TFD‑551, TFD‑950, etc.), it is sold as a 7 hp medium‑temperature compressor with around 11.9 kW nominal capacity.
Model code example: ZB50KCE‑TFD‑551 or ZB50KCE‑TFD‑950.
Technology: Hermetic scroll, part of the Summit series designed for higher seasonal efficiency.
Polyester oil (POE) on the label
The upper part of the label still shows POLYESTER OIL, confirming that the compressor is charged with POE lubricant. Catalogues list oil charges of about 2.6–2.7 l using approved POE types such as RL32‑3MAF or Mobil EAL Arctic 22 CC, depending on the variant.
POE oil absorbs moisture quickly, so systems must be evacuated deeply and fitted with quality filter‑driers.
Only compatible POE grades should be added; mixing with mineral or alkylbenzene oil is not permitted.
Technical data with hp and W
The following table compiles typical data for a Copeland ZB50KCE‑TFD‑551 running as a medium‑temperature refrigeration compressor; values may vary slightly by refrigerant and exact model.
Parameter
Typical value for ZB50KCE*
Nominal power
7 hp
Nominal capacity
11.9 kW cooling (≈11 900 W)
Electrical power input
≈7.5–7.9 kW depending on conditions
Displacement
19.8 m³/h
Supply voltage
380–420 V/3/50 Hz and 460 V/3/60 Hz (TFD code)
Maximum operating current
14.6 A
Locked‑rotor current
≈100 A
Oil type
POE (e.g. RL32‑3MAF)
Oil quantity
2.6–2.7 l
Sound level
≈64 dBA at 1 m
Net weight
≈59 kg (TFD‑551)
*Always confirm with the exact data sheet for your compressor code.
Voltage and operating limits on the sticker
On the lower part of the photographed label, remnants of “Volt 1 380 … Volt 2 460” can be identified, matching the dual‑voltage three‑phase motor used in TFD models. Another line mentions maximum current around 14.6 A, which is the value used to size breakers, contactors and cables.
The TFD motor code indicates 380–420 V/3/50 Hz and 460 V/3/60 Hz with internal motor protection.
Respecting these limits and using proper overload protection prevents overheating and nuisance trips in commercial installations.
Practical maintenance notes
For technicians such as those in Mbsmgroup and Mbsm.pro, a faded nameplate is common on older units, but the combination of model code and official catalogue restores all critical information. Creating a new service label with hp, kW, voltage, POE oil type and charge simplifies future troubleshooting and reduces the risk of mistakes during oil changes or retrofits.
When replacing or topping up oil, always isolate the compressor, recover refrigerant and work under clean, dry conditions.
If in doubt about capacity or application limits, refer to the Copeland ZB range catalogue and selection software before approving a replacement.
Copeland condensing unit for cold room – features, applications and installation tips
The condensing unit (group) is an original Copeland brand motor rated at 15 horsepower (15 HP), while the evaporator fans are Friga‑Bohn brand (two fans), both in good working condition
Equipment description
The images show a Copeland condensing unit on a steel base, with a semi‑hermetic refrigeration compressor, air‑cooled condenser with dual fans and a vertical liquid receiver, designed for a cold room at positive or low temperature. This configuration is widely used in food retail, cold storage and agro‑food applications where stable temperature and continuous duty are essential.
The ceiling‑mounted evaporator with two axial fans distributes the cold air evenly inside the room and returns refrigerant gas to the Copeland compressor through insulated suction and liquid lines. Pairing a Copeland condensing unit with a forced‑air evaporator is a classic solution that remains easy to install, commission and service for professional refrigeration contractors.
Copeland brand and technology
Copeland is a global reference in refrigeration compressors, offering scroll, semi‑hermetic and hermetic models with high energy efficiency and broad operating envelopes. Its equipment covers commercial refrigeration from medium‑temperature cold rooms to low‑temperature freezers, helping retailers and logistics operators secure the full cold chain.
Modern Copeland systems often integrate advanced protections, electronic controls and, on some ranges, Digital Scroll technology for capacity modulation, which improves temperature stability and reduces electrical consumption. For installers and companies such as Mbsmgroup or Mbsm.pro, this means more reliable systems, fewer service calls and better seasonal efficiency.
Typical features of Copeland condensing units
Although the exact nameplate of the photographed unit is not readable, Copeland catalogues describe the main features of their condensing unit ranges. These units are available with multiple refrigerants (such as R404A, R134a and newer lower‑GWP blends), and cover a wide capacity range suitable for small to large cold rooms.
Key technical characteristics (catalog examples)
Item
Typical Copeland data
Compressor type
Scroll or semi‑hermetic reciprocating, multi‑refrigerant, high efficiency.
Application range
Medium and low temperature, roughly from +12 °C down to around −40 °C depending on model.
Capacity range
Models sized for commercial cold rooms, freezers and display cases of various volumes.
Condenser
Quiet axial fans, available in standard or high‑ambient “tropical” versions.
Options
Digital Scroll capacity modulation, electronic controls, liquid line components and safety devices pre‑assembled.
These catalogue values help technicians choose a replacement unit or design a new installation based on room size, target temperature and local climate.
Installation and maintenance recommendations
When installing or refurbishing a Copeland condensing unit like the one shown, technicians should:
Inspect the compressor, liquid receiver and all brazed joints for signs of damage or leaks before charging with refrigerant.
Clean the condenser coil and verify fan operation to ensure proper condensing pressure and avoid high‑pressure trips.
It is also important to select a refrigerant approved for the specific Copeland model (as listed in the product catalogue) and to follow the prescribed oil type and charge. Adding appropriate protections – high/low pressure switches, crankcase heater, motor protection and an electronic temperature controller – increases system reliability and extends the service life of the equipment.
