USB Beverage Cooler + Microcontroller = Programmable Thermostat?
+ 
= Cheap Programmable Retrofit Thermostat
I have been thinking for a long time about this idea.
The air conditioner in my office keeps running even on nights and weekends, just because the system is old and it is difficult to fit it with a programmable thermostat. It would require several changes and would incur considerable cost.
Once I opened the thermostat in my apartment. Inside there was nothing but a thermocouple on which a glass with mercury bubble was mounted. Depending on the location of mercury bubble, the circuit would be complete or disconnected, turning the a/c on or off.
When I saw the USB beverage cooler, I thought I could hook it up to my laptop USB port and using microsoft Devcon utility and writing a batch file or something, I can turn this device on and off at a specified time. The cooling produced by this device can be used to fool the existing thermostat to turn the air conditioner off.
But glitch 1. This device is not registered as a device at all in the USB devices list. It powers up when connected to USB and starts cooling, but does not show up in USB devices list.
Then I connected it to a USB hub. Then it did not start at all. On reading the documentation, I got that this will not work with USB hub because this device eats the max power provided by USB port and thus hub cannot support it.
This is the last option I have. I have already posted it on halfbakery and got some good feedback.
Don’t have time to make this hack happen right now, as some other things are keeping me busy. But as soon as I get some time, I will give it a shot.
As suggested in halfbakery discussion, this could be a big help for rental apartments.
Any comments?
[...] to convince to homeowners, but apartment renters are hard to sell this stuff to. For that purpose, an attachment like described in this post of mine could be [...]
Installation of Programmable Thermostat in Few Easy Steps « Saving Energy said this on October 18, 2007 at 11:28 pm |
hi shall i know which microcontroller used in the interface board and what is the role of microcontroller here for this project?
Hey Mangesh,
I was thinking about doing this and if I had gone ahead, I would have most probably used Basic Stamp.
But a little market research shows that programmable controllers are available so cheap.
Still something like this could be useful. For folks like apartment renters. But as of today I am not spending time on this one.
well done, brother
I don’t want to discourage your innovation, but a nice programmable thermostat is only about $40-$50. Furthermore, they can be put on almost any system (even the old dual transformer types). The simplest solution is usually the best.
i am interested in the same project too for the control of my central air conditioning system.
so keep me in the discussion list too.