Hello! Thank you for your question about the Taco VR1816-HY1-4C2A00 circulator pump. To wire this circulator, start by disconnecting the AC power supply and removing the terminal box cover. Then, install a wiring connector into the knockout hole, ensuring that only flexible conduit is used. Next, connect the line/hot wire to the black lead and the neutral wire to the white lead. If pigtail leads are not used, trim the field wire to a strip length of 1/4" to avoid exposing wire that could cause a short at the terminal plug. Insert the Line and Neutral wires into the green terminal plug, using a small screwdriver to depress the spring tab, then release the tab to secure the wires. Lastly, please note that this model is double-insulated and no grounding wire is necessary. We hope this information helps. Thank you for visiting PlumbersStock! Have a great day!