Refrigeration control valves for industrial refrigeration systems have been an important system component since the 1920s. When a control valve fails, the result can be as significant as a more costly ...

A proportional solenoid valve is an electromagnetic valve designed to respond to a variable power input to regulate the flow of liquid and/or gas proportionately. It is used to control the flow rate ...

A newly developed pneumatic-control system provides basic valve operation, as well as detailed monitoring of electrical solenoids, sensors, wiring, and connections. Called Drive Diagnostic Link (DDL), ...

Part 1 in this series covered defrost cycle problems in heat pumps. Now, let's discuss the second major winter issue: heat pumps stuck in one mode. The customer calls and says the system won't switch ...