Spring Check Valves
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The spring style check valve has a seal on a piston. The spring keeps the valve closed until sufficient pressure pushes the piston open. The piston has a rubber seal on the end that gives a positive seal against backflow. |
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When water goes forward through the valve, the spring is compressed and the piston pushes back and allows the water through the valve. |
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When water attempts to go backwards through the valve the spring and the water pressure hold the valve closed. |
