Raspberry Pi Based Irrigation Controller

So just as a preface, I dont have many images to show with this build as it went through several phases and I simply didnt pay attention to documenting images. With that said, I figured I would share my experience for anyone looking for a super inexpensive diy solution, albiet, a bit janky if I may add…
Essentially, the first phase this project went through was with an esp8266 and two shift registers (I have 11 zones), but I quickly discovered that the wiring became messy and disheartening to look at. I have adhd and it was severely hampering my progress. I needed a more simple solution. But then I realized, OpenSprinkler! The opensprinkler software allows you to map out with GPIO pins you want to use for each sprinkler zone in the web based gui, and that means that each relay/zone can be connected directly to the gpio pins on the pi without the need for shift registers. Awesome! I had a rapsberry pi 3 A+ laying around and it is perfect for this use case. Can this be done with a zero w? Im pretty sure it can, but I cannot attest to its performance so take that with a grain of salt.
OSPi does support active High/Low switching so relay boards with those can be used, but I used two simple 8 channel relay boards from amazon. Pair that with a Hunter Pro C controller housing I found laying in the garage, some gorilla tape, cardboard, and electric tape, the previous AC adapter and I was gold. I told you it was janky, didnt I? But hey it works. OpenSprinkler is fantastic and there is a custom integration available through HACS. There is a little setup involved but once its understood, its easy to get going. Im still working on my ui integration but design creativity is definitely not my strong suit, so im open to any suggestions.
Ask any questions you may have! This post will be constantly updated, because Im cheap and I want to share inexpensive ideas. Rainmachines are expensive…

Image of the janky mess that is my madness, but hey, its working! No water hammer either!

Janky-ness, gorilla tape, cardboard and electrical tape are all good with me.

What I want to know is, what are you actually using to control the water flow? ie what are the relays connected to at the business end?

So basically, I’m reusing my last controllers AC power supply. The positive wire from the pwr source is connected to the common white wire going to the valves, and the negative lead is connected to the middle relay terminals, which are all connected together to each relay through a small wire. The zone wires are then connected to the relay on the left most point. I can’t remember the name of the ports but I believe they are referred to as the Normally Open port? I’ll have to double check that. I was concerned about water hammer due to the quick shorts these relays do, but I haven’t had any issues. Other people’s mileage may vary. I’m working on more modifications right now because I didn’t account for the intense garage ambient heat from the vehicles and the pi is running pretty warm (53 degrees).

The thing I really wanted to know is what


Last controllers were a Hunter Pro C and a Netro Sprite. The Netro was cool at first but overtime I realized that its cloud reliance was a huge flaw and I wanted to replace it. Final nail in its coffin is the lack of home assistant integration, but mostly that cloud reliance is its achilles heel. Thus, here I am.