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Victor-Mo / IRT-ESP

Nefit / Buderus iRT protocol encoder / decoder for ESP8266
GNU Lesser General Public License v3.0
22 stars 6 forks source link

Active IRT-ESP and thermostat usage #12

Open erhapp opened 3 years ago

erhapp commented 3 years ago

Would it be possible to use this firmware to monitor my iRT installation and occasionally control the temperature of my heating while keep on using the thermostat?

Victor-Mo commented 3 years ago

Because the iRT bus is very sensitive, the interface board cannot work in active mode if there is also a thermostat connected. So I do not think it is possible.

erhapp commented 3 years ago

Victor, the Proddy-firmware has the command "pin" to turn GPIO-pins on or off. Can the IRT-ESP firmware do the same? I would like to use a GPIO-pin to connect and disconnect the thermostat via a relay. This way I can switch between passive and active mode.

Victor-Mo commented 3 years ago

@erhapp The current firmware does not support the 'pin' command. I am currently working on porting the new v3 firmware from Proddy. The 'pin' command should then also be included. I am also working on a different hardware interface that should allow the interface and the thermostat to be connected at the same time. If it is possible to override the thermostat if both are connected I do not know yet.

I also want to add a bit of code that can control a relay. I am only using my interface in active mode, but I had a couple of cold mornings because something had gone wrong in my home automation. So i want to add a watchdog that if it does not receive any commands from the home automation, it falls back to a real thermostat.

But what would be your trigger to switch between the interface and the thermostat ?

erhapp commented 3 years ago

@Victor-Mo The news about to move to v3 is great. Thank you very much for the hard work.

I read in another ticket about the new hardware. I would love to try it but I should say that my current setup (BBQKees) worked from the first try. Now, I should add that the board seems somewhat picky about the power supply. At one point I tried to power it via the 24AC-port on the boiler, through a AC-DC converter. This didn't work. The ESP did function without problem but the board wasn't able to detect any communication. So back to the 5V phone charger it is.

My planned setup regarding the combination of controller board and thermostat would be very much the opposite of the way you want to work. I would like to have the thermostat do most of the work, controlling the heating on his day/night automatic schedule. I would only switch to the controller board in cases where I want to override the default temperature, eg. TV night or returning home early. As I would set the temperature using Openhab (home automation) the trigger would just be a second command send from Openhab.

Maybe there could also be some sort of fail-safe system in using a NC relay so that the board need to make an active effort in keeping the Thermostat unconnected. As for a for fail-safe with regards to the home automation system there could be a timer on the pin status. So putting the pin in the high/low (depending on circuit used) state would only last for a certain number of minutes. Receiving a new command woud reset the timer. In this way the home automation system would need to send a "heartbeat" every x number of minutes in order to keep the thermostat disconnected. This will off course means that the firmware on the board needs to do more than just switching the pin. It should at the same time also revert to passive mode.