Use the direct bury connectors to protect the controller and solenoid wires from moisture damage that can cause a short circuit.
Waterproof splice connectors provide a waterproof wire connection for wet and direct burial applications between the valve and the controller. These connectors are made of wire nut UV resistant plastic housing immersed in a waterproof silicone gel. The waterproof splice connectors provide for fast and reliable splicing of irrigation wires, designed for low voltage control wires, with 18 to 22 AWG, to a maximum of 30V.
AC solenoid: Cut the multi strand irrigation controller wire and and strip back 3/4" of the insulation from each colored wire used, including the common (white) wire, to expose the multi-strand copper conductor. Join one of the colored wires to each wire of the solenoid valve. Since there is no polarity in low voltage it doesn't matter which side is which when joining the wires together. Then connect the other wire (common) from each solenoid to the exposed white (common) wire. Install a wire nut on each side and insert into the waterproof connector, and snap the connector together.
If you have a problem with power to any of the valves installed, first visually inspect the waterproof connectors near the valve. Then inspect the controller wires to insure there are no obvious loose or damaged leads.