This is something I was also thinking about. I thought to take some two channel wall relay module from Fibaro or Qubino. They have potential-free switch contacts, so that you could switch two 24V loads, while being supplied from 230V. Qubino is more interesting despite higher price - their modules work from -10 degrees C - this is in my opinion important for outside installation. Put everything in the box - done.
The only one concern to check - z-wave relay should have some kind of autonomous Limitation of maximum ON time. So that if communication or server is down, relay would safely switch off to avoid flooding. I saw Fibaro wall relay has such parameter, but not sure about others.
Sounds like a straightforward approach. Would be cheaper for 2 separate valves as well.
I didn’t know that fibaro two ways could provide 24V as well. Which model are you referring to?
I did not think about disconnected fibaro plug behavior.
Thanks for bringing it up.
I was talking about FGS-221 or similar relays. It’s not that they can supply 24V, but they can switch 24V, because contacts are isolated from mains. But you will need extra 24V PSU for valves anyway.
hate to say it, but after spending that kind of money, you should have gone the opensprinkler way! minus the valves, would spend 150ish usd
Thanks @Artyom_Syomushkin, got it 
Actually I use a FGS-222 already.
But if I need a power supply anyway I will start with the plug (I need one anyway for another project
@Branden_Smale
I thought about it, but I have a raspberry pi running openhab somewhere else and I don’t want to use another raspi for the open sprinkler setup.
Furthermore for my purpose it’s cheaper:
50 € for switched wall plug,
23 € for water valve
14 € power supply
For a huge garden with multiple irrigation channels you are absolutely right.
I created my own controllers. I used a cheap microcontroller board with wifi (ESP8266) to control an 8 channel relay board. Communication between the microcontrollers and Openhab is done via MQTT. Openhab does all scheduling and weather compensation, the microcontrollers just switch the valves.
Openhab:
Provides user Interface (via dedicated sitemap)
Scheduling
Provides weather delay
Controller:
Programmed in Arduino IDE
Receives on / off commands from Openhab via MQTT
Provides status feedback
The most expensive part was the enclosure
ESP8266 - $4.00
Relay Board $6.50
24VAC power supply - $12.00
Orbit Weatherproof Enclosure - $30.00
Irrigation Controller.pdf (145.4 KB)
1 Like
Hardware wise I setup exactly the same.
I’m very interested how you setup oh side, esp the weather compensation part & timing.
Would you mind sharing the oh side of your setup
Would it be possible to also add e.g. a DHT sensor to this board?
I will have my system sitting i a greenhouse in which I would like to monitor temperature/humidity as well.
Valves (12 or 24 V) can be bought for about $5 piece. Here is an example.
Absolutely, This is programmed with the Arduino IDE, so you can do anything with this board that an Arduino can do.
I have tested this with both the DHT22 and ds18b20 sensors on an “official” NodeMCU board. I believe the NodeMCU boards (ESP8266 development boards) provide pinouts for 9 GPIO, so I can fit 8 relays and a temp / humidity sensor. You can probably change functionality of some of the other communication pins to get more IO. The senors log to Openhab via MQTT as well as Thingspeak via wifi. I did have problems with this particular Aliexpress version of the NodeMCU (LoLin) not appearing to support the DHT library. I’m still trying to fix that issue.
As a plus, I can also push OTA firmware updates to the controllers, so no need to plug into a computer to make a change.
The most expensive part of the controller. I have 8 sprinkler and drip zones with (2) valve manifolds. I use typical rainbird valves (~$15) and have probably a couple hundred feet of PVC in the ground, so the rest of the system wasn’t cheap 
Wouldn’t mind at all, I used the wiki as a starting point. I’ll try to put a write up together this evening. Message me if you’d like to see my configuration files. It’s quite a bit of code, too much to post here
@Spilota - i too would be keen to see more of the config/code!
As i use MySensors - id like to use a $20 Rboard https://www.itead.cc/rboard.html as the arduino/relay side, and Openhab for the logic.
Just as a side note - those valves from Ali are quite unreliable. People are installing two-three of those in series to prevent leaks.
Hmm. I will find out soon enough 
Thanks for the info. Do you have any form of encryption enabled on the MQTT communication? Mosquitto and the ESP8266 MQTT client supports ssl as far as I can see, but not the OpenHAB binding.
My concern is that if the WIFI security is breached, then there is open access to control of all MQTT controlled devices on the network!
My philosophy is that is someone wants to come hack into my wifi and mess with my sprinklers then go for it. A) I’m not that important and B) you’re wasting your talent! (Maybe I shouldn’t post that on the internet?)
I do have a watchdog timer programmed into the sprinkler controller that will shut the valve off after a set time period if it doesn’t receive a close command from OpenHab.
Hi @Spilota,
I would be greatly interested in your item and sitemap config for your dedicated weather sitemap as well as your logic to switch the valves.
Your hardware setup sounds great, but it’s far beyond my capabilities (time and brain wise) 
Based on this thread, I ordered one of the TIAO Raspberry Pi Sprinkler boards and have been using it with OpenSprinkler. It came out to about the same price as a Rachio first gen, but is much more flexible (and fun to tinker with) http://imgur.com/a/U3afk
im glad i could help someone!
Would you share more information about your setup? I’d like to set up something very similar.
My system is based off of the irrigation example on the wiki, I’ve been expanding on this as I get time. I have separate valve stations / controllers in my front and backyard.
Hardware:
- Raspberry Pi running Openhab
- (2) NodeMCU ESP8266 development boards (separate boards for frontyard and backyard zones)
- (2) 8-channel relay boards
- (2) 24VAC transformer
- (2) 5VDC power supply (USB)
System Description:
ESP8266
- Programmed in Arduino
- Controls sprinkler valves via 8 channel relay board
- Does not execute sprinkler timing logic, scheduling done in Openhab
- Receives open / close commands from Openhab
- Provides status updates to Openhab via MQTT
- Has “watchdog” timer limiting runtime of any zone, preventing lawn flooding if comms are lost
- Only one zone can run at a time
Openhab
- Allows for manual on / off via sitemap
- Provides (4) programs
- Provides weather compensation, via wunderground (or weather binding of your choice)
I put a gihub page together to host my files. Openhab files and arduino code are up there.
This code is pretty messy, I still have a to do list
- Combine code into function blocks - Suggestions welcome! I didn’t spend the time to figure out how to use functions in openhab rules (suggestions welcome!)
- Refine weather compensation, make sure run / delay decision is made at run time, not midnight
- Add items for last runtime of each zone, next scheduled runtime, and last status update received from each controller
7 Likes