Control a water valve using a Tasmota Wifi relay.
Usable for irrigation systems, residential plumbing, RV plumbing.
Follow the instructions HERE on flashing the compatible relay to Tasmota, test that you can control the relay within the Tasmota devices webpage, configure Tasmota MQTT feed to point to your myServer instance, Add the Tasmota relay to the Tasmota driver within myServer, test you can control the relay via the Tasmota Driver command list.
Simple valves have three wires: Ground, Open and Close wires. These can simply be wired like the above video shows. The Battery Ground goes to both the Ground of the valve and to the Relay Ground connection. The Open Relay wire typically would go to the Normally Closed terminal. And the Closed Relay wire goes to the relay Normally Open terminal. The Positive Battery connection goes to both power up the relay board and also to the Common terminal on the relay.
With this wiring, the relay would normally be Closed. Energizing the relay will open the relay. When the valve goes full Open travel, an internal switch will shut the valve motor off so it isn't stalled and consuming battery power. The relay will still be engaged.
Simply add a button and when it is pressed, send a "Lighting|67~On" command (or whatever the device ID assigned to your relay in the Tasmota Driver is). This will turn the relay on until you send it the "Lighting|67~Off" command that can be another button.