Hi everyone,
has anyone of you had the problem, that the solenoid valve did not close?
Probably there was a communication error between the web app and the farmbot. The Farmbot stopped moving, but the solenoid valve was still opened.
For such cases, there is a function called “Pin guard” in the hardware configs. This function will turn the output pin off after a specified time. It is only for safety, so your valve does not stay open all night for example. But it might be the case, that there was an error which interrupted the “OFF” signal.
Thanks!
But do you know why this happens? Why does it not fall back in a safe state?
I can only imagine that your turn off command did not make it through into the farmbot os, for whatever reason. If the bot is still functional he keeps the last state active which would be indeed the on command… for exactly this scenario the pinguard thibg would work out quite well…
So what pin maps to the water solenoid?
Is it 63 or D9? Or something else?
this happened to me as well - solenoid would not close water stream completely, and instead of watering my bed, it would make a small pool or pond 
Had to disasseble the valve, clean it - seen nothing inside - but there was probably some dirt stuck inside the valve which prevented it from stopping water completely.
The solution would be to add a filter for small particles (similar that is used e.g. for washing machines) before the valve.
I have not done that myself though, cause I anyway plan to add water pressure regulator - my water is from well and pressure oscillates anywhere between 0.8 PSI to (maybe) up to 3. So sometimes it would gently water the plants, but other times - it just “storms” them 
It sounds ike cbrauns valve was still energized when it should have been off. This sounds more like a software thing.
The issue you described is more mechanical, due to small particles that keep it from closing.
Looks like the water solenoid is on Pin 8. You can see it as the small number in the Peripherals part
of the Controls page.
Just as Klimbim already wrote, the command to turn of the valve may be lost and the software didn’t notice. There are a few factors that make it hard to avoid this issue, but as the software is becoming more stable every update this issue will come up less. Its recommended to enable the pin guard to avoid damage to the plants due to loads of water. Just instert your used pin number of the valve (pin 8 is standard I guess), timeout in seconds and the “safe state” that it will be put in (low for off).
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Thanks @Ascend
I knew it was most likely that (I typed D9 instead of D8)
It would be a nice to have the text “Pin Number” above that column in the WebUI.