Q
What is the stop-and-waste valves?
A
Stop-and-waste valves are usually globe valves that have a drain screw on the downstream side of the shutoff mechanism. This screw allows you to drain water from the downstream piping after you have shut off the valve. Stop-and-waste valves are useful for pipes that you need to shut down during winter, such as dedicated lines serving outdoor faucets, sprinklers, outbuildings, and the like. If you are draining an entire system, such as a summer home or cabin, however, a hose bibcock drain is the best choice.

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