Connector 1 (RSS – main communication/power connector):
1.GND
2.Not connected (NC)
3.A (RS-485 Data +)
4.B (RS-485 Data -)
5.~14V (heater-provided power – not used in my setup; powering externally instead)
Connector 2 (auxiliary):
1–4. (unused in my config)
5. 5V
Yes, you’re spot on with that observation!
I’ll upload clearer pictures of the connectors once I get a proper mating connector (currently using temporary wiring).
Also, my previous YAML code is still missing the direction pin to properly control the TTL-to-RS485 transceiver (DE/RE for transmit/receive switching). That’s the main thing holding back full bidirectional communication right now.
Thanks to github contributor mikeygnyc we now have tested and validated support for NCB devices along with additional decoded fields (device type, boiler status, operating state, controller and panel versions etc) ! Please, feel free to take the latest version from the git repo.
just got my device from htumanyan can confirm it does appear to work with my NCB 240E i am unable to confirm the hot button functionality as i do not have that set up in my plumbing. I will also have to update the device to the latest firmware from the github to confirm information from the heating loop side is coming through but early signs point to it functioning as intended
got a ton of help getting the new snapshot installed from htumanyan who was able to send me a complete snapshot that i could install using the ota update via the web interface of the device that Htumanyan put together (I am a total programming noob with enough google fu to get themselves into trouble) and im super stoked to be able to integrate my navien combi boiler into my home assistance instance deffenitly recommend this approach for anyone who is looking for a way to localy integrate navien into a smart home everything from the cable production to the assistance was amazing
One more thing if I may ask - can you check the version of your front panel - it should be printed on PCB or the case and send the pic of it?
Some other forum members with 240A2 report not having +5V there - want to understand is this a variation between front panel versions and advise everyone accordingly.
I tried to take a look at it, but I haven’t looked inside the front panel. It would need me to disassemble the front panel case. See if any of these pictures help, and let me know. .I don’t see anything else written on the case.
No no, no need to disassembly. It is on that sticker actually. It is just the picture is a bit blurry for the small font. Do you mind to take a crisper one specifically of small letters/numbers?
