Hmm, it's an enticing project title, but no progress since 2015 beyond a 2 components list. Meanwhile the market has advanced and since a few years now you can buy universal IR remote controllers with WiFi like the Broadlink RM4 and sucessors. There is a Python library for driving them. Not as cheap as $5 but closer to $50 than $100, and you can train them by capturing the codes from an existing remote.

Hay i made one for all ac and it work over internet with its custom app. and also run in local wifi

Is this project abandoned?

You show a Frigidaire window AC in your picture.

Does your unit have remote thermostat capabilities?  I'm looking into automating a Frigidaire unit, but unfortunately, the remote is very basic - temp up/down but not direct temp setting.  So there's no way to remotely command a temperature without knowing the current temp setting.

I'm wondering if the units with remote therm are different in this regard.

You could test if there are other, undocumented IR codes available. Like testing with an IR library for other codes of the same basic modulation scheme.

Other possibility: Send like 20 "down" commands, so you are sure you are at the lowest temp the unit supports, e.g.15°C and then send 5 "up" commands to reach 20°C.

This would be awesome. And since IFTTT can interface with the Nest, I'm guessing you'd be able to use your Nest via IFTTT to cool a home that doesn't have central air! 

Cool idea! Good luck

I would love to be part of this project