Home » Commercial & Industrial » Chillers » Modular Air-Cooled Screw Compression
Download R134a Modular Air Cooled Screw Chiller.pdf
Image Galery


The 230 - 430 kW models are shipped from the factory complete ready for installation and use. The unit is pressure-tested, evacuated, and fully charged with R134a and has an initial oil charge. R134a has no ozone depletion potential. It is environmentally safe and does not have a phase-out date. After assembly, a complete operation test is performed with water flowing through the cooler to assure that the refrigerating circuit operates correctly. The units can be installed on the rooftop, ground outside and so on, instead of being equipped in a special machine room. It can be widely applied in newbuilt or reconstructed industry and civil-building project, such as hotel, apartment,restaur-ant, office building, shopping mall, theater, gymnasium, hospital and so on, as well as supplies required cooling water for factories in technical process of producing, so it's especially suitable for some special locations around where there are high-level requirements for noise and environments and cooling tower are difficult to install.


High Efficiency Full Load Operation:

Utilizing new screw compressor technology, the chillers meet or exceed the performance requirements of ASHRAE 90.1. All system components are selected for optimum performance, including the condenser coil areas and evaporator sizes.


Excellent Part Load Performance:

By using compressor on each chiller, unloading characteristics and part load performance are outstanding. Integrated part load value (IPLV) is a part load performance indicator as outlined in Standard ARI 550/590-1998. The IPLV rating compares the performance of different chillers under identical conditions. When the IPLV is listed as EER (Energy Efficiency Ratio), a higher EER will indicate that the chiller's overall performance is better.


Compact Design with Small Footprint:

The chillers have a reputation for a compact design and small footprint. A small footprint can save installation costs by minimizing the size of the concrete mounting pad or reduces the amount of structural steel if the unit is mounted on the rooftop.


Quiet Operation:

The chillers are designed with quiet screw compressors. Fans are selected for good performance and lower sound levels. The attention to detail with sound is critical in the design. Small issues such as refrigerant piping, supports for piping, securing components to the structure are all important to making a quiet product. We proudly publish our sound performance.


Superior Controls:

GREE has provided the latest technology in controlling the chillers. The new controller provides a user friendly environment for the operator. The control logic is designed to provide maximum efficiency, to help provide continuing operation in unusual operating conditions through proactive controls, and to provide a history of conditions to aid in problem resolutions. Perhaps the greatest benefit is Protocol for integrating with your building automation system (BAS). The interface with the BAS standard protocols through Modbus.



The evaporator is direct expansion, shell-and-tube type with water flowing in the baffled shell side and refrigerant flowing through the tubes. The evaporator has a carbon steel fin and seamless high efficiency copper tubes roller expanded into a carbon steel tube sheet. Refrigerant heads are carbon steel with multi-pass baffles to provide oil return and are removable to permit access to the tubes from either end. For water removal, 10mm vent and drain plugs are provided on the top and bottom of the shell. An ambient air thermostat controls the heater cable. The fitted and glued in place insulation has a K factor of 0.28. The refrigerant side maximum operating pressure is 2068 kPa. The water side operating pressure is 1048 kPa. Each evaporator is designed, constructed, inspected, and stamped according to the requirements of the ASME Boiler and Pressure Vessel Code.



Condenser coils have internally enhanced seamless copper tubes arranged in a staggered row pattern. The coils are mechanically expanded into louver aluminum fins with full fin collars. A variety of optional coil material and coatings are available for corrosive atmospheres. The external condenser coils are fitted with a protective wire mesh guard. Several optional coil materials are available for corrosive atmospheres. Fans-The condenser fans are composed of corrosion resistant aluminum hub and glass-fiberreinforced polypropylene composite blades molded into a low noise airfoil section. They are designed for maximum efficiency and are statically and dynamically balanced for vibration-free operation. They are directly driven by independent motors, and positioned for vertical air discharge. The fan guards are constructed of heavy-gauge, rust-resistant, coated steel. All blades are statically and dynamically balanced for vibration-free operation. Motors-The fan motors are totally enclosed air-over, squirrel-cage type, current protected. They feature ball bearings that are double-sealed and permanently lubricated.


Microprocessor Controller:

The chiller's Unit Control Module is an innovative, modular microprocessor control design. It coordinates the actions of the chiller in an efficient manner and provides stand-alone operation of the unit. A Human Interface Panel is a standard component of the Chiller. Access to all unit controls is via the Human Interface Panel.



Suction gas cooled semi-hermetic compact twin screw compressors with high efficiency profile. Compressors are provided with high efficiency suction strainer, oil trainer crank case heater and built in safety pressure relief valve. Compressors are also provided with intelligent electronics including motor temperature monitoring, phase sequence monitoring, manual reset lockout and discharge temperature protection by PTC`s sensors. Optimized oil management ensure minimum refrigerant dilution in oil.


Water Flow Switch:

A water flow switch is available for field installation in the chilled water piping to protect against evaporator freeze-up under low, or no flow conditions. Terminals are provided in the unit control center for field connection of the water flow detection switch. A flow detection device of some type is required.


Pump Output Signal:

Provides a digital output to control a second chilled water pump. Standard unit has one pump output.


High Ambient Operation:

This option is required for operation at ambient temperatures above 46 , up to 52 or when the unit is equipped with the low ambient fan control option. The option can be ordered with any unit. Compressor loading and unloading is adaptively determined by system load, ambient air temperature and other inputs to the control algorithms.



The "W" shaped coil provides excellent headroom under the unit for inspection and service. It allows less installation space requirement. Heavy structure unit with waterproof, electro-static, polyester powder painted.

The patented design of that any unitary module can be as master module, makes various emergencies easy. Each unitary module can be combined with another module with different capacity so that different units with different cooling capacity are formed in a wider application range. Balanced running of compressor extends the lifetime of unit. The compressor of each unitary module will be started one after another to ensure less attack to power network. The design of combination of modular makes the unit compact in size and configuration, convenient in delivery and installation.







© 2000 - 2016 NIA Limited Co. All Rights Reserved. Google+