What causes excess pressure in a refrigeration system?

The presence of non-condensable gases in a refrigeration system is a significant factor that can lead to excess pressure. These gases, which are typically air or any other gases that do not condense at the operating temperature and pressure of the system, can accumulate in the refrigeration circuit. When non-condensable gases are introduced, they occupy space in the condenser or evaporator, reducing the system's capacity to exchange heat effectively. This results in higher pressures, as the refrigerant must work harder to achieve the necessary cooling effect.

In a well-functioning refrigeration system, the refrigerant undergoes phase changes, transitioning between liquid and vapor states. Non-condensables disrupt this process, leading to increased operational pressures and inefficiencies. Therefore, addressing the presence of non-condensables is crucial in maintaining optimal performance and avoiding system failures due to over-pressurization.

In contrast, high refrigerant temperatures, insufficient refrigerant flow, and low ambient temperatures each have different effects on the system's performance. While high temperatures can indeed lead to increased pressure, it is not the primary cause related to the presence of non-condensables. Moreover, insufficient refrigerant flow might lead to cooling issues but wouldn't directly cause excess pressure like non-condensables do