Automotive Service Excellence (ASE) Air Conditioner Certification Practice Exam

High-side pressure in an A/C system can be influenced by several factors, and understanding the operations of these components is key to diagnosing issues.

A broken compressor reed valve would not typically cause high-side pressure to exceed specifications. The purpose of the reed valves in a compressor is to ensure that refrigerant flows in one direction, allowing for proper compression and allowing the low-pressure side to fill with refrigerant. If the reed valve were broken, it could either lead to a loss of compression or allow refrigerant to flow back, but it wouldn't specifically cause an increase in high-side pressure. In fact, a malfunctioning reed valve often results in reduced performance, decreased pressures, or other inefficiencies.

In contrast, an overcharge of refrigerant directly impacts the pressures within the system, often leading to elevated high-side readings. Similarly, restricted airflow across the condenser prevents heat from dissipating properly, which can raise high-side pressure due to inadequate cooling. A slipping fan belt also hinders the operation of the condenser fan, further preventing heat exchange and thus contributing to high pressures. Each of these scenarios disrupts the normal operation and cooling cycle of the air conditioning system, resulting in increased high-side pressure, unlike the effect of a broken compressor reed valve.