What happens when a critically charged system is overcharged?

When a critically charged system is overcharged, it generally leads to an increase in pressure within the system. This excess refrigerant causes a heightened operating pressure in both the condenser and evaporator. The discharge temperature of a compressor typically rises as the system pressure increases because the compressor must work harder to compress the additional refrigerant.

The idea of reduced discharge temperature does not hold true in this context; instead, the discharge temperature will usually increase due to the additional load and pressure. In an overcharged system, the balance of refrigerant flow and heat exchange gets disrupted, leading to inefficiencies and potential overheating of the compressor.

Ultimately, overcharging adversely affects the system, leading to higher discharge temperatures and progressively lower compressor performance overall. Lower compressor performance can result from several issues caused by overcharging, such as increased pressure drop, improper heat exchange, and potential liquid slugging where liquid refrigerant enters the compressor.

Thus, the option that a critically charged system sees a reduced discharge temperature due to overcharging does not align with the practical realities of compressor and refrigerant behavior in these circumstances.