In a fixed bore system, higher head pressure can cause what effect?

In a fixed bore system, higher head pressure results in increased pressure within the entire refrigerant system, which affects the flow of refrigerant. As the head pressure rises, the pressure differential between the high side (where the refrigerant is subjected to high pressure) and the low side (where the refrigerant evaporates and absorbs heat) becomes more significant.

When this pressure differential increases, it can lead to more refrigerant being forced through the fixed metering device. The metering device is designed to restrict the flow of refrigerant to control the amount that enters the evaporator. However, when head pressure is high, the elevated pressure can push more refrigerant through the metering device than it would under normal conditions. This can enhance the cooling effect in the evaporator, assuming the system is functioning correctly and not overwhelmed.

Understanding this relationship is crucial for diagnosing issues in an HVAC system since an improper amount of refrigerant flow can lead to efficiency problems or overloading components.