Which valve is specified on the hot water tank piping recirculation line?

Which valve is specified on the hot water tank piping recirculation line?

• A. Globe valve on supply
• B. Gate valve on feed
• C. Ball valve on recirc
• D. Globe valve on recirc

Answer: (D)

Controlling flow in a hot-water recirculation line relies on having a valve designed for throttling rather than just turning the flow on or off. A globe valve provides smooth, linear flow control and tight shut-off, which makes it ideal for continuously regulating the amount of hot water circulating back to the tank. This lets you fine-tune the loop to maintain the desired supply temperature and minimize standby losses. Gate valves are better for on/off service but poorly suited for fine control; they can change flow in larger steps and don’t provide as predictable throttling. Ball valves are excellent for quick, full shut-off but are not intended for gradual, precise flow regulation and can cause abrupt temperature swings in a recirc system. So placing a globe valve on the recirculation line gives the best combination of control, stability, and isolation for the hot-water tank loop.

Controlling flow in a hot-water recirculation line relies on having a valve designed for throttling rather than just turning the flow on or off. A globe valve provides smooth, linear flow control and tight shut-off, which makes it ideal for continuously regulating the amount of hot water circulating back to the tank. This lets you fine-tune the loop to maintain the desired supply temperature and minimize standby losses. Gate valves are better for on/off service but poorly suited for fine control; they can change flow in larger steps and don’t provide as predictable throttling. Ball valves are excellent for quick, full shut-off but are not intended for gradual, precise flow regulation and can cause abrupt temperature swings in a recirc system. So placing a globe valve on the recirculation line gives the best combination of control, stability, and isolation for the hot-water tank loop.