REFRIGERATION SYSTEM AND A METHOD FOR REGULATING THE REFRIGERATION CAPACITY OF SUCH A SYSTEM

摘要

A refrigeration system having a rotary screw compressor (11), a condenser (12), first pressure reducing means (13), an economizer (14), second pressure reducing means (15) and an evaporator (16) is provided with an economizer channel (22, 23) connecting the economizer (14) to a closed working chamber of the compressor (11). The refrigeration capacity is regulated by a valve (17) in the economizer channel (22, 23), governed by sensing means (28) sensing a parameter of the refrigerant in the refrigeration loop, which parameter is indicative of the required refrigeration capacity. The valve (17) regulates the mass flow of gaseous refrigerant through the economizer channel. In a preferred embodiment the closed working chamber of the compressor (11) is also connectable to the compressor inlet through a return channel (23, 24), which connection also is regulated by the valve (17).