摘要 |
<p>A refrigeration system (10) which controls subcooling by controlling the amount of refrigerant diverted from the condenser (14) to the receiver (16) based upon the difference in temperature between the phase change transition temperature of the refrigerant in the condenser (14) and the liquid refrigerant temperature at the condenser output. Refrigerant is bled from the receiver (16) to charge the system until the condenser pressure causes the difference between the phase change and liquid temperatures to exceed a predetermined value. A controller (100) responds to this condition by simultaneously operating a bleed valve (32) at the receiver inlet (34) and a release valve (56) at its outlet to draw refrigerant from the condenser (14) into the receiver (16). As the condenser pressure drops, the difference between the phase change and liquid temperatures decreases toward the desired amount, and the cycle begins again.</p> |