Red Seal Sprinkler Fitter Practice Exam

What is the function of a dry pipe valve?

1. To allow water to drain from the system

2. To keep the pipe system filled with air

3. To increase water pressure in the system

4. To reduce the flow rate of water

The correct answer is: To keep the pipe system filled with air

The function of a dry pipe valve is to keep the pipe system filled with air. This is essential in applications where the sprinkler system is installed in areas that are subject to freezing temperatures. A dry pipe system remains filled with pressurized air or nitrogen, which keeps the water in the supply pipes from entering the system until the valve is activated by the heat from a fire. When a sprinkler head is triggered by heat, the dry pipe valve opens, allowing water to flow into the previously empty system and out through the activated sprinklers. This configuration ensures that there’s no water in the pipes during non-fire situations, significantly reducing the risk of pipe freezing and potential damage. The mechanical design of the dry pipe valve allows it to respond only when necessary, ensuring reliability in fire protection systems without compromising safety in cold environments.