I had a controller for a couple years that worked fine until completely dieing this spring. I replaced it with a new unit, installed in exactly the same place. The new unit goes offline every few days. Usually power cycling it a few times brings it back online.  I've even had to install a smart plug in line with the power supply so I can reset this remotely - but why does the new controller go offline every 2-3 days when the old one never did?

Added information:

At the suggestion of support, I tried a reset (pin in the front) and this did what was expected - it reset it. Some of the times it goes offline it goes into reset mode by itself - and this appears to just do the same as it was sometimes doing by itself. 

Also, it now often stays offline all the time and nothing I do other than a reset seems to bring it back online.

Just to provide further information, sometimes when it won't go online, I get the slow blinking indicating it is in setup mode. This then requires me to remove and re-add the controller - which then requires me to completely setup my garden again ( a lengthy job). It would sure be nice if I didn't have to completely reconfigure the garden each time I re-add the controller.

My updated for today - after todays factory reset, following by another garden reconfiguration, I did a manual run for each of my 4 zones. From the app, it looks like everything ran - but a physical check showed that no water was applied. The app thinks it turned on the water, but it didn't.  I'm really starting to think maybe I have a dud controller.

It now goes off-line every few minutes. Signal strength tests using various tools show the wi-fi signal is very strong right at the controller

Fyi - I did remove the common and the zone 1 wire, ran a 24v current across them and zone 1 began watering - so I know that everything downstream from the Netro controller still works.