Unless an automatic expansion valve is equipped with a bleeder or bypass, what will happen to the high side and low side pressures during the off cycle?

The correct answer indicates that during the off cycle, the high side and low side pressures will not balance unless an automatic expansion valve is equipped with a bleeder or bypass. An automatic expansion valve regulates the flow of refrigerant to ensure consistent cooling. When the system is off, without a means for pressure equalization, the high pressure on the condenser side and low pressure on the evaporator side remain isolated from each other.

The high side typically holds refrigerant at a much higher pressure because it's involved in releasing heat to the environment, while the low side operates at lower pressure, absorbing heat from the indoor space. Without a bleeder or bypass to allow some bleed-off of high-pressure refrigerant back to the low side, the pressures will remain distinct.

This differentiation in pressures is crucial for the function of the system; if they were to balance, or equalize immediately, it could lead to operational failures or inefficiencies when the system tries to start up again. Therefore, the unique pressure characteristics during the off cycle are vital to maintaining the integrity of the cooling cycle.