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Turning a Dumb AC Unit Smart (Without Losing My Security Deposit)

https://prilik.com/blog/post/automating-ac-nyc/
16•austinallegro•1h ago

Comments

effnorwood•26m ago
Hey Siri, can I afford a home loan?
clickety_clack•20m ago
You’ll need to unlock your iPhone for that.
scottlamb•25m ago
> The rest of this blog post is a walkthrough of a software engineer’s approach to home automation and building custom hardware, and let me tell you: both the final product, and the journey to get there, are hella jank.

IMHO it's not that bad? With the disclaimer that I'm also a software engineer who dabbles very very lightly with electronics and has no mechanical engineering expertise. But the overall approach of doing this by stepper motor seems quite defensible given the security deposit constraint. The only part that seems really janky to me is that it's not physically held in place that well as noted in this paragraph:

> Ultimately, the biggest issue is that binder clips and cardboard aren’t quite as robust of a mounting mechanism as I’d hoped they’d be… and over time, the stepper motor tends to “sag” a bit, resulting in a bit too much friction between the motor, the coupler, and the underlying knob, causing the mechanism to stall out until someone manually goes and reseats it…

Involving MQTT and HA can sometimes get frustrating too; having your AC not working properly if there's a problem on a Linux machine can suck. If this becomes a problem in practice, iirc ESPHome also has a thermostat component, and temperature sensors are really cheap and easy to wire in, so you could do it all on the microcontroller pretty easily in a low-code way. But if this part is working, no need to mess with it.

Reason077•7m ago
Instead of attaching the motor bracket with a binder clip, consider sticking it down with some sort of removable adhesive?

3M command strips should be very strong/secure, while also allowing for adjustment and will detach without residue when the time comes.

ethnt•3m ago
I was in a similar situation with my apartment PTAC unit, but mine has thermostat terminals — I would not be surprised if this one does too. I was able to hook up an Ecobee thermostat, with the downside being that it's way more expensive than OP's solution.