On a makeup water line that supplies a hydronic boiler, which two kinds of valves are required?

• A. A hand valve and a pressure reducing valve
• B. A globe valve
• C. A gate valve
• D. A ball valve

Answer: (A)

The essential idea is to have one valve to isolate the makeup line and another to regulate the water pressure entering the boiler. A hand valve serves as a manual shut-off so you can isolate the makeup line for service or maintenance. A pressure reducing valve lowers the incoming city water pressure to the boiler’s feedwater pressure, protecting the boiler from overpressure and ensuring proper operation. Together, these two valves provide safe, controllable makeup water supply. Other valve types listed don’t combine isolation with pressure regulation, so they don’t meet the required function.