What is the typical purpose of an expansion valve in an HVAC system?

The typical purpose of an expansion valve in an HVAC system is to regulate refrigerant flow into the evaporator. This valve plays a crucial role in controlling the amount of refrigerant that enters the evaporator coil. By doing so, it ensures that the refrigerant can effectively absorb heat from the indoor air, which is necessary for the cooling process.

When the expansion valve opens, it allows refrigerant at high pressure from the condenser to expand and turn into a low-pressure vapor as it enters the evaporator. This transformation is essential because it facilitates the refrigerant's ability to absorb heat from the air passing over the evaporator coil. Proper regulation of this flow is critical for maintaining system efficiency, temperature control, and preventing issues such as flooding or starvation of the evaporator.

In addition to its primary function, the expansion valve can also help maintain optimal pressure and temperature conditions for the refrigerant, contributing to overall system reliability and performance. Thus, the regulation of refrigerant flow into the evaporator is essential for the HVAC system's cooling and heating processes.