I've been working on a Wifi gardening project that allows me to water plants from anywhere I want. Of course, this means I need to use a water valve and a MOSFET to control it. The MOSFET feeds power from a 9V battery to the solenoid, and a Huzzah ESP8266 (on a separate 9V battery) controls the MOSFET gate.
I found that the ESP8266 would not open or close the valve, so I started testing the valve and I realized that I could not open the valve at all. The valve is a plastic 12V solenoid valve (https://www.adafruit.com/product/997), but the information on that page indicates that it can be run using 9V. As far as the 3 PSI minimum pressure requirement goes, the valve is connected to a resevoir that is 3-4 feet above the valve, so I figure that I have a decent amount of pressure from gravity.
I have almost no idea what could be going wrong - I connected the 9V battery directly to the solenoid through a breadboard and nothing happened. The only thing that seems off to me is the diode I use for reverse current protection - see the picture below. Is that diode set up correctly?
Thank you very much for your help.