The circuit cooling systems with the use of miniature refrigeration compressors have dramatically increased in popularity in recent years as they sit comfortably alongside the small footprint and high performance of modern life. They provide a compact, lightweight, reliable and powerful solution to the thermal management applications in compact or mobile space.  In this circuit, the compressor plays an essential role to pump the refrigerant gas, thus providing the system with dynamic. The miniature compressor’s capability and characteristic determins the reliability, safety, mobility, and efficiency of the micro refrigeration systems. 

So if you’re considering a refrigeration compressor replacement or you want to upgrade your compressor for a more efficient system, a right compressor selection is critically important.  It will have a positive impact on your investment. 

The following system cooling characteristics could be made and help you determine the proper the selection of a compressor for your application. 

1. Compressor Cooling Capacity 
2. Mininum Evaporator Temperature 
3. Type of Compressor 
4. Type of Refrigerant 
5. Ambient Temperature 
6. Electrical Power Available 
7. Motor’s Efficiency. 

Let’s dive right in more details. 

1.Compressor Cooling Capacity 

When selecting a miniature refrigeration compressor, the first factor to consider is the refrigeration capacity you will need. It is usually defined as the specified cooling capacity at normal working conditions of the system in watts, according to the condensing and evaporating temperatures.  The capacity is determined by the mass flow rate of refrigerant, which depends on the compressor’s dispalacement, speed range, and volumetric efficiency. 

The small refrigerated compressor at MOIR COOLING is with cooling capacity ranging from 100W~550W(1870Btu) by our controller. The controller is continously speed controlled by a sine wave signal with variable speeds from 1200RPM to 6500RPM.

2.Mininum Evaporator Temperature 

The minimum evaporating temperature and the condensing temperature allows for the identification of the compressor application(LBP, MBP, or HBP). 

The high back pressure systems such as chillers and air conditioners works best at temperature above 23°F（-5°C） whreas low back pressure systems such as freezers is perfect for compressors that operate at a temperature below -4°F(-20°C）. The medium back pressure systems such as food coolers or beverage dispensers works in a temperature between -4°F and 23°F .

3.Type of Compressor 

The rotary compressors and reciprocating compressors are the most common types of refrigeration compressors applied for refrigeration system. When at the same cooling capacity condition, the mini rotary compressor  is 40%~50% smaller volume and 40~50% lighter than the reciprocating compressor. 

While the cooling capacity for the 2 types compressor is same. You can replace reciprocation compressor directly with rotary compressor just connecting properly with suction and discharge tube. But make sure the discharge tube in rotary compressor is in high pressure end(condenser side) and so the process tube do. 

4.Type of Refrigerant 

Refrigerant selection can be made on the basis of availability, performance, and ecological considerations such as ODP( Ozone Depletion Potential) and GWP( Global Warming Potential).  All the miniature rotary compressor shipped from MOIR is filled with HFC-R134a refrigerant which has been verified. Other refrigerants or refrigerant blends, such as R12, R22, etc.,  may perform satisfactorily, but not be allowed to use yet. 

5.Ambient Temperature 

The compressor-based refrigeration unit are generally applied for indoor use, and a mininum of + 5°C is required for proper lubrication. The micro compressor selected must be suitable to operate at the highest expected room temperature. 

6.Electrical Power Available 

Generally, miniature dc compressors are used in active thermal management applications where the weight and space is crucial.  DC power is produced by batteries, vehicle, grid, solar energy, or from an AC inverter power supply.  The selection of compressor must made according to the DC voltage available. The mini compressors supplied from MOIR is available for 12V, 24V, and 48V input options and compatible with various current. 

7.Motor’s Efficiency.  

Motor is one of the major components of a compressor. The motor’s efficiecy need to be taken into consideration when selecting a refrigeration compressor.  MOIR’s motor, is the kind of Brushless Current Direct( BLDC) motor.  This type motor has fast response, large starting toruqe, and high performance providing torque from zero to rated speed. 

Beside above aspects, other factors can be kept in mind according to your unique requirement, such as your investment, space, noise levels etcs.  When understanding the application of the refrigeration system, the temperature required for storage, the selection of the compressors will be the most appropriate.  This article can help you find the right refrigeration compressor to match exactly your systems for a truly efficient and reliable performance. If you want more details about the selection, please feel free to contact our well-trained specialists. We will cooperate with you for every step of the way as per your need. 

The Features of MOIR’s Minature Refrigeration Compressors 

• Pocket Size & Small Footprint:  smallest size around the world, easily integrated into confined space, cut down shipping cost, saving floor space, perfect for mobile or compact cooling system. 
• High Reliablity: Hermetical type, less parts, less maintenance, fewer service calls, tailed for cutting-edge  equipment use under harsh conditions
• High Capacity: Compact size but with high refrigeation capacity, comparable to systems 10x the size. 
• High Efficicey: minimum power consumption, energy-saving, low power draw, and less heat rejection.

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【MOIR Service】

Supported by our factories that have been engaged in the miniature refrigeration compressors and micro refrigeration systems industry over 15 years, MOIR is capable to provide our customer with umcompromissing standard miniature compressors of ultimate performance and highest reliability.  Nowadays, the small compressors are increasingly used in a wide range of applications, including small water chillers, air conditioning units, and commercial refrigeration units.  To meet the growning market , we will continue our focus on this segment within mobile cooling.