Short-tube refrigerant flow restrictors

Abstract

Five short-tube refrigerant expansion devices, with L/D ratios from 7.5 to 11.9, were tested on a three-ton split-system heat pump. The test results show that first-stage choking has occurred at the liquid subcooling temperature of 22.2 C/sup 0/ (40.0 F/sup 0/). However, there is no indication that second-stage choking has ever occurred.