RF hacking my cloud-controlled ceiling fan

Love these write-ups, i have various 433mhz things around the home that i’ve integrated with home assistant. Probably the most useful is still a bbq thermometer with multiple probes.

Anyway i was going to post my favourite tool in this space https://github.com/jopohl/urh universal radio hacker just makes the process trivial, but i see the repo is marked archived now. Either way, the software is excellent.

Funnily enough, I did almost exactly that last week, but I kind of gave up for now as my 433 MHz transceiver does not seem to work well with esphome? It does seem to output signals when I use the remote. Oh well, I will revisit when I have more time.

A major difference is that I relied on a flipper zero I had to do the 433 MHz capture instead of an RTL-SDR (I have one too, but have not needed it yet).

For reference, the transceiver is the one that came with this product: https://www.athom.tech/blank-1/8ch-inching-self-lock-relay-f... (which I already use for controlling a heater). Weirdly, it is not listed in the official esphome config (possibly because RF is a recent addition to esphome). My next step is to test it on another esp board & compare timings with what esphome generates.

I should start doing write-ups too. I came across quite a few interesting sources during this mini project (2-3 hours max).

Thanks for sharing - i have been on a few years long journey trying to control my swamp cooler while try to learn RF. I started with a flipper zero to see if i could even capture signals from remote, replay and then decode via URH. i was able to brute force my way through it with older AI models 'back in the day'. I had it basically just send a 'cool' signal while remote was set to vent (which means no water flow).

The humidity in the house could then be measured with a RH sensor and the controller could then send cool signal to add some water to the pads if RH dropped below a certain point. This keeps the humidity way down while only increasing temp by 1-2 degrees. So much more comfortable as i can now keep the RH in the 50-60% range base on outside conditions.

I recently picked the project back up and with newer Claude models i have been making significant progress. For one, the code to determine when to 'cool' is getting better at managing as outside conditions change - temp/RH etc outside impacts cooler performance. Second, I can now start to fully replace the remote so the code manages via feedback loop. the remote has a keep alive sync signal that i was able to figure out that prevented me from using just the eps32. if the remote was off, the controller would turn on the cooler fine but if i didnt send a keep alive, the cooler eventually shuts off.

I have also added a RX module that allows me to now listen for the remote signal and shut off controller when i turn off via remote. eg turn on cooler via remote and controller can be turned on/off to work its magic.

Ultimate goal is to maintain the RH in house all day while outside conditions vary - morning, afternoon, evening and storms etc and then turn off at night once certain conditions are met. My wifes request is to have it turn off at bedtime so she can fall asleep, then turn back on after about 1 hour - so a timer is future feature.

The one thing I have learned is RF is hard but satisfying to figure out - I would have never attempted learning this w/o Claude. I also have a meter reader esp32 i am still working to debug and feel confident i can figure it out.

I'm working on there exact path since a few months to make this process feel magical to people who can run Home Assistant, but rf capture and replay is too technical. I'm using evilcrow-rf for it and goal is to provide trivial setup flow so that copying rf remotes feels easier than signing up with the company you bought your device from. Hopefully I'll be able to do a show hn in near future.

https://github.com/meowtochondria/EvilCrowRF-V2

I do not have a home so perhaps I do not fully understand. If it is warm when I go to bed, I turn on the ceiling fan by rotating the knob next to the bed. When I wake up, I turn it off. What kind of automation are you looking for?

Good write up Sam!

I bought a cheapo tuya wifi fan controller for a "dumb" ceiling fan. Connect to it from SmartThings app on my phone. The app can be paired with siri and now I can just say: "living room fan on/off". Works great.