There are not many dedicated sprinkler controllers on the internet that can be integrated with Home Assistant. Moreover, most available electromagnetic valves use AC, which creates the problem of needing an additional power supply to get them working. Nowadays, you can buy DC coils (for example, Hunter makes some), but they are much more expensive.
Solution used so far.
Previously, I used a modified LILYGO T-Relay with an external WiFi antenna. It worked reliably, but as mentioned, it required a DC power supply for the T-Relay and AC for the coils. After a few years of reliable operation, I added another watering section to my garden. However, since I used a T-Relay with 4 relays and none were free anymore, I needed to find a new solution.
New possible solutions:
Additional Relay:
The ESP32 board has enough GPIOs to control many more relays, but due to the external DC PSU, I ran out of space in the hermetic box. Buying a new one was not an option because the old one was already too big.
Design own PCB:
Years ago, I designed my own PCBs, but now I’m older, lazier, and don’t have as much time. Like the previous proposal, this idea was also rejected.
Find an Out-of-the-Box Solution:
Solutions from big companies are usually very expensive and often cannot be integrated with Home Assistant.
After days of searching online, I was unable to find any suitable solution for controlling 24 ACV valves over ZigBee. Moreover, WiFi-based solutions are also limited to Tuya Cloud.
Summary.
It is very hard to find a solution that fits the needs of cloud-independent home automation.
Experiment.
During research for another project, I found that it’s possible to bypass Tuya Cloud using different tools, so I decided to buy a controller like the one shown below.
