Air conditioning IT pros. Part I

Air conditioning IT pros. Part I


Penny, everything gets better when there is bluetooth © Sheldon, TBBT

Although the house " test ", but everyone tried to do as correctly as possible - good insulation, decent double-glazed windows, etc.

In winter, in clear weather, the sun warmed up the house to the condition that the heating with heated floors was turned off by a thermostat. Everything seems to be fine, but spring has come and it has become clear that the house just overheats and needs to be cooled.

We foresaw this scenario and prepared in advance for the installation of an air conditioner: we laid all the necessary highways during the construction phase.

About windows
In general, of course, it would be worthwhile to put double-glazed windows with MF and I-glasses, but here “A double-edged sword” (as always, however) - in winter they would receive less free heat from the sun.

Ideally, it would be better to figure out what is more profitable: use an electric underfloor heating floor less for heating during a cold period or use an air conditioner for cooling less - during a warm one, and on the basis of such an analysis, choose which double-glazed windows are more correct to install.

But no one has done such an analysis, so we have what we have.

By the way, neither the builders nor the windowlayers recommended which glass units it would be better to use in our case. Everything has to be dealt with independently (including paying for mistakes).

One of the important criteria for choosing an air conditioner for my “test house” is the possibility of its integration into the " smart home system ".

Integration is "cheap and cheerful"
Of course, the simplest integration of almost any air conditioner is using the commands of the IR remote. But this option does not suit me for ideological reasons: there is no information about the current state of the device.

Therefore, this option is immediately dismissed and move on.

Flour Selection


Naturally, the other parameters are also very important (from the main priorities: maximum quiet operation, energy class not lower than “A”, price).

The choice fell on the inverter Electrolux (Atrium series). The manufacturer explicitly indicates that the air conditioner is Disturbing "bell"
For some reason, the supplier somehow hesitates about the WiFi module and in every way evades it deliveries under various pretexts. Now I understand that this is a “bell”, but we are going further.

Google help, manuals and other information - (sort of like) the Electrolux ECH/WF-01 Smart Wi-Fi module is required. And there is no shortage at all (this module is also used for water heaters and electric convectors of the same manufacturer) and the price is more than affordable - less than a thousand rubles (in general, it should also be a little alarm). The management application is one for all these types of devices, which looks quite reasonable: the manufacturer wants an “ecosystem” to form.

A little more research (peeped code regular Android application) and it turns out that the application communicates with the cloud at:
dongle.rusklimat.ru/api - yeah, it becomes even more interesting and immediately there are thoughts about how it will be necessary to ensure integration with the smart home system (UD).

"Ringing" number two
One of the sites caught a customer review, where he told that the cloud was often "lying around "And initially he waited and tormented technical support for about two months before the system started working as stated. The review is quite old - I thought that I had already fixed the problems and everything will be fine.

Split system has been ordered, the day of the installation is scheduled - everything is clear: a couple of hours and a pleasant coolness is ensured.



Now it's time to order an optional module.

Rakes


A smart WiFi module arrived — nothing special about it: a coarse “flash drive” with a single button and an LED that glows dimly through the case (of course, when connected to power).



I first stuck it in a laptop (I must take a look at what the module “pretends to be”) ... but there was not a single device in the system (I was surprised, but for some reason it was not very strong).

Okay, let's try to use it in a regular way: the module occupied the corresponding connector in the indoor unit of the air conditioner.



The reverse side of the display board


I installed the program and followed the instructions: I pressed the button on the module for five seconds - he started blinking with a yellow LED (Smartlink mode), in the dialog box that appeared, indicated the name of the wifi network and the password to it ... the LED on the module blinked and turned blue (according to the instructions - normal mode).

Although everything was done according to the instructions, the device did not appear in the program (various fears are being justified).

Well, okay, we move on and try to understand what we are dealing with - we look into the web interface of the router. Router - showed that the new wifi-device is connected and working (hurray, a small victory and something still works).

At the same time, the router passed this module as glassware: the name of the new host is “HF-LPT220”.

A quick search revealed that this is a UART-WiFi SoC (about $ 5 for retail units and 60-80 cents for bulk purchases).

Autopsy revealed that the patient died from an autopsy


Disconnect the module from the air conditioner and open the case of this whistle (it opens easily and closes easily).



In the photo above you can see that the router told the true truth: a “three-kopeck” module with minimal strapping (power stabilizer, LED (two-color), button, level converter) - it became clear that even the requested price for this module is clearly overestimated (ok , we will assume that there was also a payment for the work of programmers who were supposed to write a firmware that would provide the necessary functionality).

Pay attention to the signed contacts of the usb connector (from usb - only the connector body and the same location of the power pins) - it is therefore not surprising that the module was not identified by the computer.



Thus, the automation of control of this air conditioner - can be done on anything (even on the Arduino) - you just need to know what commands the system expects to receive.

But we don’t have this information about the teams.

Thought Vectors


Actually, since all the components on hand have some additional information about what we actually have, the following options seem logical:

  1. Analysis of the network exchange was the idea to implement a “proxy server” to which to transfer the initial exchange between the air conditioner and the “cloud” (using the router's tools), and from this “proxy” to organize interaction with the “cloud”. Then this server can be integrated into the smart home system - at the same time, it would be possible to achieve work both through a standard application for the air conditioner and control through the UD (automatic scripts, etc.).
  2. Connect the computer through the USB-UART module to the internal unit of the system, select the exchange rate and “listen” to what the air conditioner informs the module (I want to believe that the exchange goes regardless of whether the standard module is connected or not). Hope that after receiving commands from the IR remote control, the air conditioner executes them and sends the appropriate message via the WiFi module to the “cloud” to display the current status. And hope that the developers are lazy and these messages are identical to the commands received from the WiFi module.
  3. Connect your computer through the USB-UART module to the WiFi module and try using the standard application to “steer” the air conditioner and receive commands from the WiFi module for the split system. The option is very promising for analysis, but, unfortunately, my air conditioner did not appear in the standard application (for the time being) - therefore sending commands from the phone is not possible.

Attempts


Since the regular application did not start with the WiFi module, I started from the simplest — I went according to option 2: I took the USB-UART and connected to the indoor unit of the air conditioner.

Unfortunately, the option did not bring the result - the split-system “is silent” at all exchange rates and does not react to external stimuli in any way. Apparently, a “protection against hacking” is built in: probably, the original WiFi module sends some data, according to which the main unit recognizes it as “its own” and conducts an exchange.

While I was dealing with my hypothesis, I wrote several letters: to Electrolux and mobile software developers.

Electrolux


In reality, all the HVAC equipment under the Electrolux brand was officially supplied by the Rusclimat company (my first acquaintance with this company was about 10 years ago and it was far from pleasant, but this is another story). Therefore, I was not very surprised when, in response to a request on the Electrolux website, I came from a technical specialist of Rusklimat.

Well, the answer was with such a meaning that the module that I purchased does not fit air conditioners, but there is still no “suitable” one and is only expected in the middle of July 2019.

Mobile Software Developers


The developer of software for Rusklimata is Ipol LLC. The developers responded that in the current version the air conditioners are not supported at all and when asked to “share the exchange protocol,” of course, they answered that they did not disclose such information.

End?


Of course not! Now it only remains to wait for the manufacturer to release the “compatible” WiFi module and repeat all the reverse engineering vectors, but with the “correct” module.

In the meantime, I am returning to the automation option “cheap and cheerful” (it is necessary to control the operation of the air conditioner with the help of a surveillance camera - the internal unit is just in the frame).

If suddenly someone comes up with how to do it right after all, I will be glad to give you a hint. And if someone has already “passed this way” and shares the exchange protocol - I will be just happy;)

By the way, in the depths of the internal block a very interesting information plate was discovered, which gives a couple more new “vectors”:



P.S."Part II" with a detailed description of the solution "cheap and cheerful" will be later (you only need time to find).

P.P.S. “Part III” with the “right” solution, I hope, will appear after the purchase of a compatible module (it remains to wait until it becomes available).

Source text: Air conditioning IT pros. Part I