What can cause high-pressure levels in an A/C system?

High-pressure levels in an A/C system can result from overcharging with refrigerant or blockages. When too much refrigerant is added to the system, it creates an excess that can lead to increased pressure in the evaporator and condenser coils. This is because the refrigerant has nowhere else to go, leading to a buildup of pressure that can cause the system to operate inefficiently or even fail.

Blockages within the system, such as in the expansion valve, filter drier, or evaporator coils, can also result in high-pressure buildup. When airflow is restricted by these blockages, proper circulation of the refrigerant is hampered, causing pressure to rise significantly.

In contrast, fluctuations in temperature do not directly cause high-pressure levels. They can affect system performance in various ways, but they are not a primary driver of high pressure. Excessive airflow typically helps to reduce pressure by enhancing heat exchange, while low refrigerant levels would lead to low pressure due to insufficient refrigerant in the system to absorb heat effectively.