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Air Con: $1697 for an on/off switch

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Re: Air Con: $1697 for an on/off switch

#261

Post by csunbird »

cuu508 wrote: post #239
hellweaver666 wrote: post #232

I had a similar situation with my shutter blinds. The company wanted €500 to install a "smart hub" to enable voice control instead of their little remote. To hell with that, I ordered a couple of servos and an esp8266 and 3d printed some little fingers that would press the buttons on the remote and added the whole thing to HomeAssistant via ESPHome. Cost me less than €30.

I disassembled one of our gate opener's remotes, and hooked the button contacts to Raspberry Pi Zero's GPIO pins. Pi runs a tiny go webserver and Cloudflare tunnel. I hit an obscure HTTPS URL (via button on a phone's homescreen), gate opens.

I remember someone posting something about their garage opening whenever they open safari, as Safari replays GET requests from open tabs when it is un-suspended, although can't find the post right now.

Basically, they had your setup exactly, but they leave the tab open in Safari and whenever they open Safari to browse the internet, the garage door opens.

Re: Air Con: $1697 for an on/off switch

#262

Post by fmbb »

audunw wrote: post #220
zeroflow wrote: post #207

Earlier quoted context omitted.

I'm offering you a different viewpoint: They made the analysis, how long the flash will live and saw, that it will make it out of the warranty period. Thus they did not opt for more durable and expensive flash and/or software change. I've seen this myself before. One process step before release of the control module was a write cycle analysis to make sure the unit will live for at least 10 years (i think) before the…

You're both missing one of the more likely explanation.. that nobody gave much thought about how long the device would last. "It's solid state electronics, it'll probably outlast the warranty anyway".. I can imagine an aircon company puts a lot of effort into analyzing the air-conditioning unit itself to make sure it lasts at least as long as the warranty, with good margin. But I can totally see them winging it on an…

Never attribute to laziness or stupidity that which is adequately explained by the profit motive.

Re: Air Con: $1697 for an on/off switch

#263

Post by stavros »

radicalbyte wrote: post #192
gstar wrote: post #70

OMFG; I am in Perth, I have the same system, the very same problem and solved it almost the same way and was in the process of writing it up. The system uses RS422, with a base64 encoded AES key in the aaservice binary, and I was contemplating building an esp32 based open source implementation of the controller. That's a crazy weird coincidence.

Reading the original post, wouldn't be a super cool idea to make a little ESP or RPI based system which acted as a controller for the airco and a network bridge? Then literally anything could interface with it. You wouldn't even need to wire it up. No need to install some shitty app from a company who are quite clearly c*ts.

What evidence do you have that the company is composed of cats?

Re: Air Con: $1697 for an on/off switch

#264

Post by relaxing »

datahack wrote: post #100
cyberax wrote: post #98

Ugh. The whole "smart aircon" industry needs a good-sized asteroid wiping them out of the existence. There is a very real need for modern variable-speed units, and vendors just keep fucking it up by using proprietary protocols locked into their ecosystem. TRANE in the US is similar. And this is really annoying because variable-speed pumps solve all the problems with short cycling and oversized systems.

You think this is bad? Try swimming pool equipment.

Tell us about that!

Re: Air Con: $1697 for an on/off switch

#265

Post by Hendrikto »

liminalsunset wrote: post #226
cyberax wrote: post #98

Ugh. The whole "smart aircon" industry needs a good-sized asteroid wiping them out of the existence. There is a very real need for modern variable-speed units, and vendors just keep fucking it up by using proprietary protocols locked into their ecosystem. TRANE in the US is similar. And this is really annoying because variable-speed pumps solve all the problems with short cycling and oversized systems.

The problem with having standards for this kind of thing is that different units have different needs for communication and different levels of being smart. For example, some units want 2 temperature sensors and some want 3. The method used to control the system can be relatively complex - some systems are using physical models of the characteristics and positioning of sensors to do fancy control, and there are proba…

Are you a lobbyist? You spent so much effort arguing for something OP has shown to be just plain false.

Any tablet worked. The only reason it die not work ootb were completely arbitrary restrictions.

The control boxes can do whatever complicated things they want. But the interface to control them should and can be standardized.

Re: Air Con: $1697 for an on/off switch

#268

Post by mschuster91 »

torginus wrote: post #233
pzlarsson wrote: post #120

Earlier quoted context omitted.

I think home EV charging equipment is heading in the same direction as well. Very few have local and open APIs and instead depend on the vendors cloud service for control.

I am confused - aren't these boxes basically fancy three phase outlets? They probably have some safety fuses and some comms equipment, but the 'core' of the system is basically copper wire that connects you to the grid.

> aren't these boxes basically fancy three phase outlets?

That entirely depends LOL

So for AC chargers you are correct - 1 or 3 phases that go through a relay and, where required by code such as in Germany, a DC-sensitive RCBO, plus a small control board negotiating with the vehicle and monitoring voltage/current on one side and, again depending on where required by code, negotiating with the grid operator.

DC chargers are one hell of another beast, these have to contain all of the above plus powerful rectifiers, smoothing capacitors, EMI compliance...

Re: Air Con: $1697 for an on/off switch

#269

Post by FLT8 »

nehz wrote: post #163
gstar wrote: post #77

Earlier quoted context omitted.

Oh, and you just need one of these and a TTL to RS422 converter off aliexpress to replicate the interface: https://www.aliexpress.com/item/1005005918675239.html The connectors on the small RJ45 daughter board are JST-SH 1.0 The yellow lead puts out 4.2v to replicate a Li-Ion battery (as far as I can tell). You can ignore this. Red is positive Black is negative Green is usb d+ Blue is usb d-

Would you have the RJ45 pinout too? Thanks!

This is from my earlier notes, hope it helps some.

  Pin 1: RS422 +/B
  Pin 2: RS422 -/A
  Pin 3: ? - appears to be unused; connected to unpopulated pad on PCB
  Pin 4: GND
  Pin 5: ~14.2v DC unloaded
  Pin 6: GND
  Pin 7: ?
  Pin 8: ?
  Shield: GND
Note: the RS422 protocol has a basic bus arbitration built-in to allow both ends to communicate. The control unit sends Ping messages, after which it opens a slot for the Tablet to communicate back to it. At least on my system xx represents a simple CRC value that can be used to validate message authenticity. I haven't seen any AES encryption in use, messages I've seen are all plaintext, maybe the AES encryption was introduced in a later revision.

Re: Air Con: $1697 for an on/off switch

#270

Post by squarefoot »

I had AC installed in my new house just after putting solar a few months ago, and I was very clear that I wouldn't use anything that would depend on any external services: no apps, no connections, nothing: if I want to monitor the inverter I have to go up there to read its screen (1), and AC have to be all usable with IR remotes.

(1) I'm working on monitoring the inverter (Deye) thru a RS485 interface using a small SBC that connects to the IoT restricted VLAN. Will report here as soon as it's ready but will require time. I wonder if the same could be achieved with the AC units (Hisense). One could learn remote signals and send them say from a ESP* board through WiFi, but there would be no feedback from the AC units.

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