Question about the possibility to use a sonoff instead of a relais

[relax81]

Hi,
at first thank you very much for the project. I was just thinking about a diy sous vide solution and then found this project.

From your experience ... does it have to switch the relais very quickly on and off or is it more like a minute on, then off, a minute on, then off and so on?

I'm asking because I'm wondering if it would be possible to replace the relais with a SonOff basic switch (5$) connected to the cooking device running Tasmota or so. This way it could be turned on by wifi or mqtt and there wouldn't be any physical connection between the temperature sensor connected to the esp8266 controller and the actual switch controlling the cooker. There would probably a delay of a second or two everytime it has to switch.

[RainmanJS]

There are already a few wifi sous vide programs out there that use MQTT. Personally, and I don't know the author, I think the beauty of this particular project is that it doesn't require an MQTT broker on the network, it can all be handled by the ESP8266.

That being said, It looks like, with a few minor changes, this project could run on a Sonoff Basic. I have it running on one with the DS18B20 connected to a header soldered to the programming pins. Next to the 3.3v, Rx, Tx, and GND pins is GPIO 14, which you can use as the data line for the sensor. This makes a nice self-contained device that shouldn't even require a wifi network around to use. I noticed in his example code for the PID library, you can even get an LED to light when the system is at the setpoint.