The HydroGEN PRO is the world’s first and only water cooled CO2 generator. Water cooling can remove 86% of the heat produced by burning propane and has many features not available in any other CO2 generator on the market. The unit can easily be used in a closed-loop system with a small chiller and reservoir, or you can connect directly to your home water supply and drain to storage for reuse in your garden. Compact for easy placement. This optional valve (used in place of a pump) is designed to be installed in a pressurized water line and to be controlled by your CO2 monitor. This is a high quality solid brass valve designed for years of service. The valve has 1/2” NPT outlets that can be used with your existing plumbing or you can install on ˝” hose barbs to make the connection. You will need either a pump or a valve but not both. 1 Year Warranty.