Tasmota Valve Actuator

revC Tasmota ESP32 Floor Heating Valve Controller | Voltlog 397

Welcome to a new Voltlog, today I’m gonna be showing you revC for the ESP32 based thermostat valve controller, we’re going to do some thermal measurements using my InfraRed PCB inspection thermal camera, talk about resistor power dissipation a little bit and I’m also going to be talking about the future of this project, some changes that I might do in a future revision and ask your feedback in the comments below about these.

As mentioned in Voltlog #395, where I showed revB, I wanted to do this rather small change and release revC just to see if it was possible to improve the thermals of the board, in particular how warm these current limiting resistor networks get during operation.

revB Tasmota ESP32 Floor Heating Valve Controller | Voltlog 395

Welcome to a new Voltlog, today I’m gonna be showing you revB for the ESP32 based thermostat valve controller, this is based on revA that I first showed in Voltog #383. So a few words about this board, just in case you haven’t seen Voltlog #383. It’s based on an ESP32 and I designed it so that it’s compatible with the open source firmware called TASMOTA and that allows us to control it via MQTT from homeassistant.

We have 10 individually switched triacs, each capable of up to 900mA or 1.2A depending on the version of the triac that it’s equipped with and a few expansion capabilities via I2C, 1Wire and some spare GPIOs. Everything was designed to fit inside one of these inexpensive, DIN rail enclosures and the whole purpose of this is to allow smart control of electrical thermostat actuators.

In my case, I use these 240V rated electrical thermostat actuators to control zone valves for my floor heating system. but if you would like to know more, I recommend you also watch Voltlog #383.

So why did we need revB? Well I’ll tell you all about the changes that happened in revB and I’m gonna start with this odd shape that you see around the ESP32 module, I removed the PCB from under the antenna section of the wifi module and although the improvement is probably marginal, in theory at least, it helps to keep the antenna clear of other objects.

Tasmota ESP32 Floor Heating Valve Controller | Voltlog 383

Welcome to a new project video, today I’m gonna be presenting this 10 channel valve actuator controller which I built with the purpose of individually controlling the water circuits on my floor heating system. The best part is that this is based on an ESP32, it’s TASMOTA compatible so it should be very easy for me to integrate this into my HomeAssistant smart home system.

So like I mentioned, the need for such a valve actuator circuit started when I installed floor heating into my apartment and if you ask why i didn’t use one of the commercially available options: I don’t like them, they’re expensive and they typically only work with their closed source ecosystem, I wanted something that runs open-source so I can control and customize various aspects.

I have a total of 9 circuits and these circuits have different lengths and the rooms have different sizes so putting the same volume of water through all circuits is going to result in uneven heating. This issue can be mitigated by tuning the individual flow valves on the intake of each circuit but that setting seems to vary with the pressure it gets from the pump and doesn’t allow a fine granular control over the temperature of that room which is what I want to achieve.