What is the function of the check valve in a minimum pressure valve?

The function of the check valve in a minimum pressure valve is to prevent reverse flow of the air flow. This is essential in systems where maintaining a unidirectional flow is necessary for proper operation. By allowing fluid to flow in only one direction and blocking it from returning, the check valve helps maintain the necessary pressure within the system, ensuring that the equipment operates efficiently and safely. This is particularly important in situations where backflow could lead to issues such as contamination of the system, inefficient operation, or even equipment damage. By preventing reverse flow, the check valve contributes to the reliability and integrity of the pressure regulation system.