Before a condenser can convert gas to a liquid, what must occur to the gas?

For a condenser to effectively convert gas into a liquid, the gas must first undergo a process called de-superheating. When a gas is heated beyond its saturation temperature at a given pressure, it exists in a state known as superheated. In this state, the gas holds more energy than it would if it were just at its boiling point.

De-superheating is essential because it removes the excess heat from the superheated gas before it enters the condenser. This reduction in temperature allows the gas to reach its saturation point, where it can then commence the phase change from gas to liquid. If the gas remains superheated, the condenser will be unable to condense the gas effectively, as it would still be in a vapor form and require additional cooling.

While the processes of expansion and sub-cooling may also play roles in different aspects of refrigerant cycles, de-superheating specifically addresses the need to bring the superheated vapor down to its saturation point effectively before any condensation can begin.