The 23XL Hermetic Screw Liquid Chiller

Featuring the 23XL compressor

The 23XL from Carrier is the industry's first and only centrifugal class screw chiller. With an ideal balance of features - efficiency, reliability, quiet operation, and field serviceability, the 23XL is the best value for medium sized commercial applications such as schools, hospitals, manufacturing facilities, and office buildings.






The 23XL chiller utilizes a unique twin rotor screw compressor. Because the 23XL was to compete in what was traditionally a centrifugal chiller market, Carrier engineers determined that the screw compressor could not sacrifice in any critical area, including efficiency, reliability, sound, and serviceability. The result is the industry's first and only centrifugal class screw compressor; a robust design, world-class in every sense.

Unlike chillers which incorporate air compressors adapted for air-conditioning duty, the 23XL utilizes a compressor designed and optimized for air conditioning applications. As a result, it suffers from none of the compromises associated with misapplied technology.

High efficiency - Because one of the primary factors to consider when purchasing a chiller is operating cost, efficiency is of paramount importance. The 23XL compressor provides outstanding efficiency at full load and throughout it's part-load operating range. This high efficiency, leveraged by advanced internally and externally enhanced heat exchanger tubes, results in operating costs among the lowest in the industry.

Carrier has achieved high efficiency compression by combining an optimized design with ultra precise compressor tolerances. By utilizing proprietary manufacturing techniques available only recently, in conjunction with high precision bearings, the 23XL screw rotors are positioned with clearances measured in microns!

Reliability - It's not unusual for Carrier chillers to last thirty years, or longer! With this tradition in mind, Carrier designed the 23XL for the long haul, and achieved centrifugal class, world class reliability. With proper preventative maintenance, twenty, even thirty years of service is definitely possible.

Of course, with the compressor being the heart of the chiller, it was there that Carrier engineers concentrated their efforts most heavily. Every component was scrutinized in an exhaustive process of analysis, design, and testing. Particular attention was paid to the critical moving elements; the rotors, bearings, and slide valve. Let's look at each of these separately.

Rotors - The rotors are the defining element of any screw compressor.

The rotors used in the 23XL were designed specifically

to compress refrigerant vapor for air-conditioning

applications. Their computer optimized

profiles are key in achieving high

efficiency throughout a broad

envelope of load and lift

conditions. This is a

hallmark of the

23XL design.



Bearings - The bearing system in the 23XL compressor was designed to accommodate the high loading associated with air-cooled chiller duty. But the 23XL chiller is water-cooled, and this duty creates much lower loads. The bearing system therefore operates very conservatively loaded. Add to this the fact that the bearings are AFBMA class 5 rolling element type, the same type utilized in jet engines and machine tool spindle applications. Clearly this robustness significantly enhances long term reliability.

Capacity control slide valve - Here, Carrier engineers applied their innovation in creating a unique design that locates this critical device below the rotors rather than above them. In this design, gravity accurately and repeatably positions the valve in it's bore. The resulting tight tolerances contribute to high efficiency. An extra benefit is that the bottom-mounted design minimizes the wear potential resulting from rubbing between the slide valve and rotors, a problem inherent in top-mounted designs.

Sound - An inherently quiet design makes the 23XL chiller ideal for acoustically demanding applications, usually without the need for costly field applied acoustic insulation.

Serviceability - The 23XL compressor is unique in that it is the air-conditioning industry's first and only fully field-serviceable screw compressor. This allows routine maintenance and inspections to occur in the field, dramatically reducing expense and machine downtime. The alternative is a compressor which must be sent back to the manufacturer's factory for exchange; a costly and time consuming procedure.










An abundance of additional features further contributes to the robust quality of the centrifugal class 23XL screw compressor.

With an exceptional combination of efficiency, reliability, quiet operation, and serviceability, the 23XL compressor clearly demonstrates true centrifugal class. For your water-cooled screw chiller applications, let the 23XL compressor set the standard, and choose the 23XL chiller to meet your needs.