I love my Nest.
If you want a beautiful, intuitive, "luxury" piece of modern technology to run your HVAC, go for it. It's all about the little things - the way it feels and clicks when you turn the dial to change the temperature, or how it "wakes up" when you walk up to it. It's not an ugly white box on the wall. The web UI for programming is very easy too.
Don't buy it for the potential savings though. You can get most of the energy saving features in cheaper packages. Auto-away is nice but you'll get better savings if you manually set it to away as soon as you leave.
I understand that the system is self learning but I am wondering if it can accept multiple sensors and distinguish between say myself and my tenant and if it can sense the temperature in different parts of the house and incorporate that it into the feedback loop.
Nest only "links up" to other Nests, which would be cost prohibitive for what you describe. I wouldn't be surprised to see Nest sell something along these lines in the future though. I'd love this myself - I have a two-story with only one blower, and keeping the upstairs and downstairs comfortable could use some extra smarts.
I saw that the nest provides some detailed reporting on when the system is turned on/off. I am trying to figure out if there are any savings from turning the system on / off at various points of the day or if it is more cost-effective to just ensure the temperature in the house never drops below a certain point.
a) Are there any testing methodologies for this kind of thing?
b) Would something like the Nest help in the tracking and tweaking of such settings?
The smaller the differential between the internal and external temperature, the slower energy leaks out.
The only good reason to maintain a minimum or maximum temperature is to protect things from freezing (pipes) or melting (candles).
In any event, the Nest energy reports will allow you to experiment and get nice feedback about what impact the changes you're making have on your energy bill. You can see it down to when it cycles on and off, or just cumulative daily usage.
I do not have central air but as a bonus, I am wondering if I could use something like the Nest to monitor and track window or portable A/C usage. Its not a need but if I am going to buy a new A/C this summer, I'd as soon buy one that could plug into the system and help keep energy costs down.
Certainly should be do-able as long as you buy something that can utilize 24v line level connections (connect to Rc and Y). And even if it did not, you could rig something up with a 24vdc transformer and a relay.
What main brand models is the Nest competing with? I don't mind looking at other solutions if they are a better fit for what I am attempting.
3M/Filtrete, Honeywell wifi VisionPro, various Zwave solutions (Schlage/Trane)--
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