Hitachi AC H-link with ESPhome

ESPHome
41

Hi lumixen

You were right there was an inversion between GPIO16 and GPIO17.
Now it’s working perfectly.

Thanks for you help

42

Hi Xiong,

I have modified GPIO16 & GPIO17 in Yaml and now it’s working perfectly. But I had to disconnect pin4 first make a test then reconnect pin4 then it started working. It seems than Just let pin 2 connected was necessary to reinitialize the ac.

Thanks for your help

43

Hi,thx a lot for this work.
I implemented it on a HITACH RAK-35RPD and ist works perfectly.

The only little “bug” is the fact, that i can not fix the vertical swing to my desired position. With old remote control i just stopped swinging and then the postion was fixed. Now in the HA after stoppping swing it returns to the orignal parking position.

Any idea how to solve this issue?

44

Hi @dotvav,

I came across your Hackaday project (Project | Hitachi Yutampo serial connection | Hackaday.io) and was wondering if you’ve made any progress since earlier this year on controlling this water heater? It would be really convenient to be able to manage it remotely when going away on vacation :slight_smile:

Thanks!

45

Hi there. No I haven’t been able to make more progress. I am not able to communicate with the system on the serial interface and I am only able to observe some kind of heartbeat from it. There us no publicly documented protocol and I guess I’d need to buy an existing compatible device and snoop on the communication. I am curious but also don’t have that much of a critical use case to justify the investment, without any guarantee of success.

46

Thanks @dotvav !

So the protocol used natively by these thermodynamic water heaters (Yutampo) is different from the standard H-LINK used on air-to-air or air-to-water units? Is the ATW-HCD-01 adapter essentially bridging this proprietary water heater protocol to standard H-LINK?

If so, in theory, adding the ATW-HCD-01 should make it compatible with standard H-LINK solutions (like the ESP32 setup used for air-to-air units). However, the ATW-HCD-01 is expensive and hard to find, so we’re back to square one…

Ultimately, what we’re missing is this Yutampo-to-H-LINK protocol translation.