Chapter 25 Installation and Troubleshooting of Domestic Refrigerators and Freezers 665 Copyright Goodheart-Willcox Co., Inc. 8 Condenser Evaporator Compressor Hot-gas line Solenoid valve Filter-drier High-pressure vapor Low-pressure liquid High-pressure liquid Low-pressure vapor Goodheart-Willcox Publisher Figure 25-31. Diagram of a hot-gas defrost system with solenoid valve stuck open.