Which key element is NOT part of an air conditioning system?

An air conditioning system typically consists of several key components that work together to cool and dehumidify the air within a space. The compressor, evaporator coil, and fan are all essential elements of this system.

The compressor is responsible for circulating refrigerant throughout the system, compressing it to increase its pressure and temperature before it moves to the condenser. The evaporator coil absorbs heat from the air in the indoor environment, allowing the refrigerant to evaporate and cool down the air that is then blown into the living space by the fan.

In contrast, a temperature and pressure relief valve is not a standard part of an air conditioning system. Such valves are typically used in other systems, like water heaters or boilers, to prevent excess pressure build-up and to relieve pressure in case of overheating. This makes it clear that while crucial for certain applications, the temperature and pressure relief valve does not function in the same way and thus does not play a role in the operation of an air conditioning system.