Which is better, a scroll compressor or a rotary compressor?- Ningbo Ouyu Import & Export Co., Ltd

In modern air conditioning and refrigeration systems, the compressor is undoubtedly the core component, playing the role of its "heart." The mainstream household and light commercial air conditioning compressors on the market fall into two main categories: Scroll Compressors and rotary compressors.

Content

1 The Working Principle of a Scroll Compressor
2 Advantages of Scroll Compressors
3 In-depth understanding: Rotary Compressor
4 Characteristics of rotary compressors
5 Scroll vs. Rotary: Comprehensive Comparison
- 5.1 For those seeking ultimate energy efficiency, quiet operation, and reliability (e.g., central air conditioning, high-end split units, multi-split systems):
- 5.2 For those prioritizing cost-effectiveness and compact size (e.g., residential split units, bedroom air conditioners):

The Working Principle of a Scroll Compressor

The working principle of a scroll compressor is based on two meshing scroll plates, one fixed and the other rotating eccentrically. Refrigerant gas is drawn in and trapped in the crescent-shaped cavity formed by these two scroll plates. As the scroll plates rotate, the volume of the cavity gradually decreases, thereby compressing the refrigerant gas. This design achieves a continuous and smooth gas compression process, greatly reducing reciprocating moving parts.

Advantages of Scroll Compressors

High Energy Efficiency Ratio (EER/SEER): Because the gas compression process is continuous and smooth with less leakage loss, Scroll Compressors typically have higher volumetric efficiency, meaning they can provide more cooling capacity with the same energy consumption.

Low noise and low vibration: The smooth rotary motion replaces the reciprocating motion of the piston, resulting in very low mechanical vibration and noise during scroll compressor operation, making it particularly suitable for applications requiring high quietness.

High reliability and long lifespan: The scroll plate contact uses a flexible seal, which is more resistant to liquid slugging (a small amount of liquid refrigerant entering the compressor). With fewer moving parts, the failure rate is lower, and the service life is relatively longer.

In-depth understanding: Rotary Compressor

The working principle of a rotary compressor: A rotary compressor, typically a single-rotor or twin-rotor design, uses one or more rollers (rotors) that rotate eccentrically within a cylinder. The change in space between the rollers and the cylinder wall completes the intake, compression, and discharge of gas. This design is relatively simple and compact.

Characteristics of rotary compressors

Compact structure and low cost: Rotary compressors are simple in design, small in size, and lightweight, resulting in relatively low production costs, making them very popular in economical residential air conditioners.
Suitable for small displacement: Rotary compressors perform excellently in applications with smaller displacement (lower cooling capacity).
Energy Efficiency and Reliability: While modern rotary compressors (especially twin-rotor inverter compressors) have made significant improvements in energy efficiency, their volumetric efficiency and durability may still be slightly inferior to Scroll Compressors in high-load or large-displacement applications.

Scroll vs. Rotary: Comprehensive Comparison

Features	Scroll compressor	Rotary compressors:	Conclusion/Application Scenarios
Energy Efficiency	High (continuous compression, low leakage)	Medium to high (depending on single/twin rotor and inverter technology)	Scroll turbines offer significant advantages under high load and variable frequency conditions.
Noise/Vibration	Extremely low (smooth rotation, no reciprocating motion)	Lower (but generally higher than scroll compressors)	For applications requiring high noise levels, scroll turbines are the preferred choice.
Reliability and Lifespan	High (resistant to liquid slugging, few moving parts)	Medium to high (simple structure, but seal wear needs to be considered)	Scroll turbines are better suited for long-term, high-intensity operation.
Application Displacement	Medium to large displacement (excellent performance above 3 horsepower)	Primarily small displacement (common in 1-2 horsepower household air conditioners)	Scroll turbines are the mainstream choice for light commercial and multi-split air conditioning systems.
Manufacturing Cost	Higher	Lower	Rotary turbines have advantages in cost-sensitive home air conditioning systems.

The answer to the question "Which is better, a scroll compressor or a rotary compressor?" is not absolute, but depends on your specific application and budget:

For those seeking ultimate energy efficiency, quiet operation, and reliability (e.g., central air conditioning, high-end split units, multi-split systems):

Scroll compressors are the better choice. They offer significant advantages in smooth operation, sustained energy efficiency, and system stability, especially suitable for scenarios requiring long-term operation and large cooling capacity.

For those prioritizing cost-effectiveness and compact size (e.g., residential split units, bedroom air conditioners):

Rotary compressors are a more affordable option. Modern inverter rotary compressors offer satisfactory energy efficiency and performance even in the small-displacement segment, offering excellent value for money.

Therefore, if you are purchasing a high-power or high-end inverter refrigeration system, seeing "using a high-performance scroll compressor" is usually a sign of high quality. When making purchasing decisions, please consider energy efficiency ratio, noise level, and expected service life as key factors.