Georgia Commercial Driver License Practice Test

What is the purpose of a one-way check valve in an air brake system?

1. To enhance braking power

2. To prevent air from escaping if the air compressor has a leak

3. To allow air to flow in both directions

4. To increase air tank pressure

The correct answer is: To prevent air from escaping if the air compressor has a leak

The purpose of a one-way check valve in an air brake system is to prevent air from escaping if there is a leak in the air compressor. This is crucial for maintaining the integrity of the braking system. If the air compressor develops a leak, it could lead to a loss of air pressure, ultimately causing the brakes to malfunction. The one-way check valve ensures that air can flow into the brake system but does not allow it to escape back towards the compressor, thereby helping to maintain the necessary air pressure for effective braking functionality. Other options such as enhancing braking power or increasing air tank pressure do not accurately describe the function of a one-way check valve, which is specifically designed to manage air flow direction. Similarly, a one-way check valve does not allow air to flow in both directions, which would render its leak prevention capability ineffective.