A couple of weeks ago, we replaced the original heater that was installed when we built our house in 1988. I chronicled that tale in a recent post on this other blog.

One of the things I'm really impressed with is the spiffy new thermostat and its shinyness.

See when you're like me, the thermostat is one of the last things you think too much about. I think our original one was programmable (which saves a lot at night), but it got busted in the chops a few too many times, so had to be replaced with a new programmable control. But this was was subject to all sorts of abuse over the years. I think I remember one of my kids smashing it in frustration. Such violence!

The new unit is quite pretty and seems to have some nifty programming options.

Since this new equipment is replacing what we had before, it would be a pain if the installer had to run a new wire between the HVAC and the fancy thermostat. But this one is designed to run over the existing four-lead wire that controlled the older system. That's pretty clever - the furnace even supplies power to the touch screen.

Of course, I immediately start thinking about what chip and operating system might be behind that lovely piece of touch-sensitive glass. I can't find any reference to "Linux" on the Lennox.com web site, and I'm sure they would have a source offer available if they used GPL software. But what really got me thinking was what else you could do with this system.

The HVAC installers asked us if we wanted to wait a few weeks for a new type thermostat which is connected by wifi to the internet. We were told that the new kit would allow us to control our home's temperature from anywhere in the world using our phones or ipads.

I can't say I have ever had a time in my life when I wished I could remote control my homes temperature from a browers. (Program the DVR? Yes, many times, but not the temperature).

Lennox iComfort WiKFi brochure is here. The brochure shows a lot of young, hip executives with their smart phones controlling the Lennox furnace. (As opposed to the brochure for the thermostat we got which shows a lot of much older people. Boo! We got the old folks thermostat.)

Frankly, I am also a little worried about yet another internet-connected embedded device connecting to my home WiFi, which might be poorly firewalled and could be subverted by someone with the intent of doing harm to my home.

Can you imagine the spectre of homes all over the world being cranked up to max temperature by some terrorist cell or enemy government? Oh the horror! Oh the humanity! Seriously, it would be much worst to have thermostats subverted into a bot net, or perhaps sniffing for credit card numbers.

Another interesting option for smart thermostats is the Nest Thermostat, which does indeed have a source offer available (though there is a link at the top of the page which is broken). So you can see clearly all of the open source software in use, including connman, which is a very cool project that we make use of in the Yocto Project to initiate and manage a variety of network connections.

I love the minimalist-retro design of the Nest too. Very low profile and unobtrusive and it's reminiscent of the old dial thermostats of my childhood. I wouldn't mind trying one of these out, though I fear that the complex HVAC I have might not integrate terribly well with a differently smart system.

The Nest looks like the perfect project for using the Yocto Project to build and maintain their embedded Linux system. Perhaps they already do, or will do so some day.

So I'm guessing Dave Lennox doesn't use Linux, which is unfortunate. But I do wonder what's under the covers. I'm not about to rip apart my new thermostat to find out. Being without heat is something I don't look forward to. I'll leave that research to someone else.