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Power Hardware Technology

Making a Learning Thermostat 192

OzPeter writes "As reported in WA Today, Tony Fadell of iPod fame has been using Nest Labs to design and build a thermostat that learns how you live in your house by following how you manually change the temperature. Once you have taught it how to behave, it then can schedule temperature changes that suit your lifestyle, and help you cut down on energy costs."

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Making a Learning Thermostat

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  • Women (Score:5, Funny)

    by Dan East ( 318230 ) on Thursday October 27, 2011 @06:22PM (#37862768) Journal

    Don't let women use this thing. It will only learn two settings: the maximum temperature setting and the lowest temperature setting. At least that's how the females in my life use them.

    • by cvtan ( 752695 )
      This is absolutely true. Apparently heating systems (even totally automated ones with thermostats) have only two settings: on and off. If you want the temp to be 72, you set it to 85 so it heats up "faster", then when it's too hot, you turn it off. The temperature is always wrong so you have to keep adjusting. It makes you feel needed.
      • by ooloogi ( 313154 )

        For some reason people tend to assume a proportional controller, and want to help it out doing its job.

        • Confusingly, the air conditioners in cars that have temperature settings usually are proportional, to my great irritation. My car has one of those dial-a-temp things. I hate it, but I would have had to do without the sat nav and nice stereo to get the "normal" climate controls.
          • by Firehed ( 942385 )

            Maybe the one in your car just sucks?

            Seriously - not trolling here.

            I was looking at options available for a potential next car, and when I saw the Auto AC option paused for a minute. "Why would I pay extra for this? I never touch my car's climate controls." And then the smacking of forehead - that means it was doing precisely what I wanted. The only time I never interact with it is to turn the actual AC (vs just blowers) off if I'm driving with the windows open. Other than that it's been left alone with ou

            • It might just suck, but I've never been happy with those when riding in someone else's car, either. I think I'm just picky about it. I adjust mine pretty constantly to give me what I want. It's especially troublesome when I'm running the AC to dehumidify and subsequently having to heat the air. It's a Toyota, FWIW.
        • by Ihmhi ( 1206036 )

          Perhaps they equate the gas lines as being exactly the same as the water lines?

          If the water in the shower is too cold, you dial the heat way up and then dial it back when it gets to where you like it. They probably assume the same thing for thermostats.

          • by rtb61 ( 674572 )

            Air-conditioning is completely different. It will only reduce the temperature of the air over the indoor coil by the capacity of it's compressor, the size of the evaporator and condenser coils and outside temperature. The amount of cooling achieved and how long it takes, depends upon internal heat loads, insulation values and volume of air to be treated.

            Whether it's a dial or digital read out, the result is the same. Getting to your desired temperature will not be achieved faster by turning the dial or

        • by Sycraft-fu ( 314770 ) on Thursday October 27, 2011 @09:52PM (#37864254)

          Really, I was surprised, but I have one on my A/C. So my A/C is a dual stage unit. Basically it has a bypass so that when it doesn't need to put out so much cooling, it can work the compressor less, spin down the fans, and so on. When needed, it can use full capacity. It is a 4 ton unit that effectively has about a 2.5 ton mode. Good for saving energy. Most days all you need is the first stage, even in the desert.

          Well the thing is, the stage use is determined by two degree bands, temperature deltas. The first you set between 1 and 6 degrees. This is how much the temperature can swing before the unit engages. So if the degree band is 3 and the thermostat is 75, the A/C will come on at 78 (or the heat at 72 if in heat mode). The second one is another two degrees fixed. When the temperature is more than the first band plus the second, the thermostat engages the second stage of the A/C. So if set at 75 with a 3 degree band, the second stage engages at 80 degrees.

          Needless to say the thing cools a hell of a lot more when fully spun up. So you really can make it cool down faster by setting the temperature lower.

          In fact, I have to when it is really hot. When it is very hot, like 105 or above out, the low stage is really only enough to maintain the temperature. It cools as fast as heat leaks in (that is the design idea more or less). So to actually get it to cool, I have to kick in the 2nd stage. Means if I want 75, I set the temperature lower, until it hits 75, then set it to 74 and the A/C will continually run until the outdoor temperature cools off enough.

          And yes, it is more efficient to run continuously in the low stage than cycle on and off in the high stage.

    • I'll be impressed if someone can teach my wife that setting the thermostat lower doesn't do anything on a really hot day if the air conditioner can't keep up. I've explained this repeatedly, but she keeps trying to set the thermostat to 68 on a 100 degree July day. And this is a woman with 3 science degrees!

    • On the off chance that a woman is reading slashdot right now; care to explain this phenomenon to us males. I don't know any men who do this or any women who don't. What is it about having ovaries that makes a person treat an infinitely adjustable feedback temperature control element like a binary on-off switch?
      • Most likely as there is no negative feedback for doing so, but there is positive feedback for using other systems this way. It's like the C and CE buttons on calculators, if you want to set your calculator to a known "safe" state it's generally easier to just hit both buttons a few times than learn what the buttons actually do (especially since not all calculators behave exactly the same when it comes to these buttons, much like not every heating or cooling system behaves exactly the same, I've seen thermos

  • by LunaticTippy ( 872397 ) on Thursday October 27, 2011 @06:23PM (#37862784)
    Most thermostats will learn stupid conflicted behavior. Cold person irrationally turns thermostat up to 80. Angry frugal person retaliates by turning down to 50. Repeat 20x/day. Leave it alone at random during nice weather.

    I like thermostats that are more even-tempered. My programmable one has a nice feature that if overridden will resume at the next programmed temperature interval, so someone cranking the heat or AC will only be able to influence the next few hours at most.
    • Hmm, I have an idea. A truly smart thermostat would lie. It would indicate it's set at some crazy temperature, but in reality it would apply a moderate setting. Or better yet, it would lie to everyone but me.

      • by kd5zex ( 1030436 )

        I just filed for a patent on this, thanks!

      • Re:Learned Stupidity (Score:5, Informative)

        by NEDHead ( 1651195 ) on Thursday October 27, 2011 @06:36PM (#37862892)

        It is a well documented fact that in some office environments, fake thermostats that the workers can access improves perceived comfort and reduces calls to maintenance.

        • Combine the two approaches with facial-recognition thermostats that tell the lies that each user wants to hear.

        • by BillX ( 307153 )

          And for everyone else, it is a real one locked behind a little plexiglass cage... with a can of computer duster / cold spray sitting on top of it.

        • Just if someone is interested, a year ago there was a Slashdot discussion [slashdot.org] about these dummy things, including thermostats.
      • Hmm, I have an idea. A truly smart thermostat would lie. It would indicate it's set at some crazy temperature, but in reality it would apply a moderate setting. Or better yet, it would lie to everyone but me.

        You work for the CIA, don't you?

      • Interesting thing: I have no clue what brand it is but my brother's thermostat does something like this. No matter how big of a change you set it to, it will not accept a jump larger than, I don't know, 4 degrees? In a single change. It's 74 and you want colder? Tell it 50 and it will, after a few minutes, bounce to 70. Once it's 70 you can then go back at it and try to lower it further.

        I am not sure if in his the threshold is user configured or not.

        • I have one of the higher end honeywell models (like $200 for the control panel + remote logic box) that has all sorts of fun options. Maximum adjustment increment, overall max/min settings, etc.

          The biggest features I got it for are the external temp sensor which the thermostat uses to adjust the humidifier run time to avoid condensation in the winter and the smart recovery. The thermostat uses a combination of outside + inside temps and some recent historical data (how fast did the house cool down or heat u

          • Does that really work well? I've got a programmable thermostat (though not that nice of one) and setting it to pull the house temp up for waking up results in hot air in all the rooms while the walls warm up. (I have to leave doors closed to keep the cats out of the bedrooms, but there's at least a 1" gap under every door so we can have good air exchange.)
      • How about a talking thermostat with a personality. Something in the vain of Red Dwarf's talking toaster. :)

      • I have a fancy programmable thermostat, and it actually does allow you to specify in the setup menu how much you want it to "lie", and in which direction.

    • by BasilBrush ( 643681 ) on Thursday October 27, 2011 @06:32PM (#37862860)

      Cold person irrationally turns thermostat up to 80. Angry frugal person retaliates by turning down to 50. Repeat 20x/day.

      Ah, but the thermostat also has the information of what the temperature actually is when they turn the dial.
      Cold person turns it up at temp X, frugal person turns it down at temp Y.
      X is too cold, Y is too warm. Good compromise temperature is between X and Y.
      80 & 50 are irrelevant.

      The whole point of this rethink is to look at heuristics like that. Not just to learn, but to be intelligent about it.

      • by cynyr ( 703126 )

        Does this concept thermostat understand multiple rooms, and that some rooms may be in the sun and others might not? can it control room dampers? how about handle a complex ground source heatpump, gas furnace, water heater, water heater preheat, etc setup? any sort of communication protocol?

        Sorry forgot we were in the residential market and not the commercial. Other than missing some really helpful new install features, i agree that looking at these heuristics would be helpful, but it would be helpful to hav

        • by cynyr ( 703126 )

          hate to reply to my self, but

          Can this handle an ERV in the system as well and check indoor and out door humidity as well as CO2 levels?

          • by Qzukk ( 229616 )

            check indoor and out door humidity

            I've posted this before, but what I really want out on my programmable thermostat is a dehumidify cycle that runs for 15 minutes or so then goes back to the default setting.

      • So take away the temperature number on the control, just have warmer and colder buttons.
        • by adolf ( 21054 )

          Why even have warmer and colder buttons? That just encourages people to mash buttons in ways that are likely to be confusing to the system. "I feel chilly" = "Mash Warmer button a dozen times and curse the infernal box."

          Such a system could be even simpler if it had two buttons, one labeled "Bad" and the other labeled "Good."

          If the temperature is to your liking, you push the "Good" button. If it is not, you push the "Bad" button. Do this whenever you walk by (it's supposed to be in a busy hallway, after

    • by Rich0 ( 548339 )

      What you need is a reasonable set of zones, and in each zone a temperature/humidity sensor, an occupancy sensor, and buttons that say "too hot" and "too cold" with no numeric display of temperature.

      If you are uncomfortable you hit the too hot or too cold buttons, and that is your only feedback mechanism. The system might take into account spamming the button, but certainly not linearly. The system then just needs to learn when zones are occupied and what kinds of conditions are "too hot" and "too cold" at

  • I live in the South and have a 19 SEER variable speed AC/Heat Pump and this can't control it yet.

    • by cynyr ( 703126 )

      you should toss in some room dampers, and use that heat pump to pre heat your water for your hot water heater and let me know when/if this works for that sort of a set up.

  • by hawguy ( 1600213 ) on Thursday October 27, 2011 @06:35PM (#37862888)

    Sounds overly complicated. With my current thermostat, I set it to make the temperature to 70 degrees at 6:55am (just before my alarm goes off). It learns how fast the house heats up, so the house really is at the right temperature when I want it to be and it does a pretty good job of that, even on unusually cold days.

    If I have to manually adjust the temperature to help it learn, then it's going to lag my preferred time by 5 or 10 minutes (the time it takes me to get out of bed and go down to the thermostat and reset it). Or does it learn how long it takes me to get dressed and walk from the bedroom to the thermostat? And if it uses motion sensors to decide whether or not I'm home, it's either going to think I'm never home since I don't go past the thermostat much in my day-to-day activities, or it's going to think I'm always home when it senses the dog going to her food dish.

    I'd much rather have a thermostat with an easy to use UI than something that tries to be smart. Maybe if I had a true smart-home with sensors in every room, it could automatically figure out what time I wake up and when I leave the house, but I don't see how a thermostat on a wall can do a good job.

    • by JBMcB ( 73720 )

      I don't know if you saw the nest - but it's just a knob. You turn it until it's at the temperature you want. That's it. No fan control, no heat/cool setting. It just makes it the temperature you want. Then, as you turn it up and down, it learns *when* you want it to be a certain temperature. It also checks via wifi what the temperature outside is, so it learns the delta between preferred indoor and outdoor temperatures (we keep our thermostat at 68, but if it's 65 and sunny outside we turn the furnace off)

      I

      • by hawguy ( 1600213 )

        I don't know if you saw the nest - but it's just a knob. You turn it until it's at the temperature you want. That's it. No fan control, no heat/cool setting. It just makes it the temperature you want. Then, as you turn it up and down, it learns *when* you want it to be a certain temperature. It also checks via wifi what the temperature outside is, so it learns the delta between preferred indoor and outdoor temperatures (we keep our thermostat at 68, but if it's 65 and sunny outside we turn the furnace off)

        It seems pretty nifty, if for no other reason you can set it via the web if you aren't coming home as scheduled.

        That's my point - it thinks it knows when I want the temperature to be set - but instead, it has to guess based on incomplete information. Just because I don't put on my clothes and come down to the thermostat until 7:20 doesn't mean that I don't want my bedroom to be warm when I jump out of bed at 7am. Likewise, just because I don't walk past the thermostat from 9am to 5pm doesn't mean that I'm not upstairs working in my office.

        My thermostat doesn't need to know what the weather is like outside because i

    • by BasilBrush ( 643681 ) on Thursday October 27, 2011 @07:01PM (#37863086)

      Or does it learn how long it takes me to get dressed and walk from the bedroom to the thermostat?

      If it's occurred to you in the few minutes between learning about the device and posting here, why would you imagine that it hasn't occurred to them? There's no reason why it can't work out which is the morning increase, and assume that in future you want that temperature 10 minutes earlier in the day, or 5, or 20, depending on what their research in the field has found to be satisfactory for most people.

      And if it uses motion sensors to decide whether or not I'm home, it's either going to think I'm never home since I don't go past the thermostat much in my day-to-day activities, or it's going to think I'm always home when it senses the dog going to her food dish.

      They say the best place for thermostat is in a hallway. People should be passing that from time to time. But they do say to turn it down yourself hen leaving and up when you return, at least for the first week, to give it a good start on working out your patterns.

      And placed at the normal thermostat height, the detector isn't set off by dogs. That's a FAQ.

      I'd much rather have a thermostat with an easy to use UI than something that tries to be smart.

      I've never seen an easier UI than this one. There's only one control and that's a temperature dial. Personally I'd far prefer one that's smart.

      I don't see how a thermostat on a wall can do a good job.

      Ah well, if you can't see it, then obviously it doesn't work.

      "No wireless. Less space than a nomad. Lame."

      • by hawguy ( 1600213 )

        Or does it learn how long it takes me to get dressed and walk from the bedroom to the thermostat?

        If it's occurred to you in the few minutes between learning about the device and posting here, why would you imagine that it hasn't occurred to them? There's no reason why it can't work out which is the morning increase, and assume that in future you want that temperature 10 minutes earlier in the day, or 5, or 20, depending on what their research in the field has found to be satisfactory for most people.

        That's my point - they don't know so they have to guess. So it's somewhere between 5 or 30 minutes so it's either going to be too short or too long for many people.

        And if it uses motion sensors to decide whether or not I'm home, it's either going to think I'm never home since I don't go past the thermostat much in my day-to-day activities, or it's going to think I'm always home when it senses the dog going to her food dish.

        They say the best place for thermostat is in a hallway. People should be passing that from time to time. But they do say to turn it down yourself hen leaving and up when you return, at least for the first week, to give it a good start on working out your patterns.

        My thermostat *is* in a hallway, but it's a little used hallway that leads to the front door, I'm much more likely to bypass the hallway and go to the kitchen when I'm working at home.

        And placed at the normal thermostat height, the detector isn't set off by dogs. That's a FAQ.

        A FAQ is not quite the same as a fact. My alarm installer told me the same thing when he installed motion sensors, and he had to come take them out after my dog pro

        • A FAQ is not quite the same as a fact. My alarm installer told me the same thing when he installed motion sensors

          The information from the person who designed the device is rather more trustworthy than from some guy in a boiler suit. If it's a FAQ answer, that is indeed the way it works.

          It's simple as long as you trust the thermostat to know your patterns better than you do.

          Thats not the question. The question is whether after learning it reflects your behaviour better than the settings you programmed into your old thermostat - which may be out of date. And whether you'd prefer to be relieved of the chore of setting the thermostat program every time your shedule changes.

          Or maybe different people live in different homes, so one product doesn't work everywhere?

          An AC said it best:
          HI, I'm Clippy,

      • by rhakka ( 224319 )

        who the heck told you the best place for a thermostat is in a hallway? that's the WORST place for a thermostat. unless your hallway happens to be on an outside wall with a significant heating/cooling load profile. Jeez... hallway thermostats are one of the reasons most people are not happy with their heat/cooling systems and are constantly fiddling with their thermostats.

        I too dislike the autoaway feature, but as long as it's configurable I don't see a problem.

        the autolearning programming is a GREAT idea

        • who the heck told you the best place for a thermostat is in a hallway?

          Oh, I can't remember. It's something I've known for a long time. A central hallway, AWAY from outside walls, exterior doors and away from radiators and other sources of local heat. I was prepared to think I might have it wrong. But then I thought back to homes I've lived in over the years, and most of the thermostats were indeed in the hallway, and I didn't put them there. So then I thought, heck, lets check it out on Wikipedia.

          Household thermostat location
          The thermostat should be located away from the roo

    • Simply because it still requires you to tell it which mode it is in, heating or cooling. The motion sensor is a gimmick as many will not have these items in areas where the traffic is during the day. I certainly have not seen a house with one in the kitchen, breakfast area, office, or bedroom outside of the master, so how useful is that? Let alone, do you have pets? How will it know a bird in a cage is there (I don't have one, but a motion sensor won't pick it up either)

      Comfort range should be independent o

  • There are a fair number of people who don't pay for their utilities when they rent apartments. This is especially true in buildings that have minimal individual temp control. I don't need to pay for my utilities. I'm pretty sure that in general I'm less careful about say not leaving windows open than I would be if I had to pay for using heat dumping as a way of cooling my apartment when the heat is too high. I feel guilty about that doing that but hey. In a similar vein, I suspect that lots of people who d
    • There are a fair number of people who don't pay for their utilities when they rent apartments. This is especially true in buildings that have minimal individual temp control. I don't need to pay for my utilities. I'm pretty sure that in general I'm less careful about say not leaving windows open than I would be if I had to pay for using heat dumping as a way of cooling my apartment when the heat is too high. I feel guilty about that doing that but hey. In a similar vein, I suspect that lots of people who do control the temperatures would keep them down if the thermostat instead of displaying just the temperature displayed the actual cost accumulating. That's probably a lot technically simpler than trainable AI.

      I live in an apt with baseboard hot water that I don't pay for. There's one manual thermostat in my unit and it takes a while for the heat to be even throughout, so I found it best just leaving it set to 20C unless I'm going to be away for weeks. If I were paying for the heat I would probably install a programmable thermostat to try and save, but I'm not as wasteful as some of the other tenants in my building that set it to 25 and leave the windows open.

      If I had a programmable thermostat it would be 15 at n

      • by cynyr ( 703126 )

        hehe, every spring and fall I end up with the hot water baseboards on, and the windows wide open. Changing the setting on the thing (from 1 to 5 dots no real temps) will not shut it off completely, and when it is 74 and sunny out, the last thing I need on is the heat. It's fun here in the spring and fall, 30's at night 70's-80's during the day and a weekly high temp swing of 50F 70 for the high on monday, 20 on Friday.

      • by necro81 ( 917438 )

        If I were paying for the heat I would probably install a programmable thermostat to try and save

        So.... why not just do that? It takes all of five minutes to wire in a thermostat (2-3 wires), and just about as long to remove it. Your landlord doesn't need to know, and you get some satisfaction about not being so wasteful. Better yet, ask your landlord for permission - he or she may even subsidize the cost, because they are paying for the waste.

        Is the only reason anybody tries to conserve is because t

  • Seriously, I know what temperature I want the house, and the 'smart' thermostat can only guess. Given that we start and leave work at various different and largely random times during the week it has no chance in hell of getting its guesses right except by luck.

    Why does everyone think we want to deal with hardware that does seemingly random things based on its conception of what I want it to do, rather than doing what I want it to do? This is even more of an abomination than Google's 'smart' searches which

    • According to the developers of Nest, 90% of programmable thermostats aren't programmed properly. Maybe you're in the 10% and wouldn't benefit. That doesn't mean it's not a good product for many of the 90%.

      Just one thing:
      "Given that we start and leave work at various different and largely random times during the week it has no chance in hell of getting its guesses right except by luck."

      On feature of Nest might be an improvement for you then. You can set the temperature remotely from computer or smartphone. W

      • According to the developers of Nest, 90% of programmable thermostats aren't programmed properly. Maybe you're in the 10% and wouldn't benefit. That doesn't mean it's not a good product for many of the 90%.

        So according to the people with a solution, there's a problem that needs fixing! I sincerely doubt their numbers. Really it's not that hard, and the last one I bought had a energy star setting system built in. I tweeked it a bit, but I could have installed it, and just left it. Further, anybody whose capable of installing one of these things can program it. Same goes for the wonderthingie, well except I can get a programmable thermostat for $50, while this is 5x the price. Maybe people who can't progr

        • So according to the people with a solution, there's a problem that needs fixing! I sincerely doubt their numbers. Really it's not that hard

          Everyone overestimates the number of people that are the same as them in some way.

          Maybe Nest are exaggerating. They said "according to one study", but they could be lying. But you have NOTHING to go on other than your estimation of the number of people that are like you.

          Same goes for the wonderthingie, well except I can get a programmable thermostat for $50, while this is 5x the price. Maybe people who can't program a thermostat, or install one can't do math either....

          Or maybe they just have deeper pockets than you. Or maybe they realise that they haven't re-programmed the thermostat in the last year at least, and actually a thermostat that learns from the overrides is a good idea. That it'll probably

      • Lots of people have pets at home that aren't going to be comfortable with the temperature swings that energy efficiency would dictate.
      • According to the developers of Nest, 90% of programmable thermostats aren't programmed properly. Maybe you're in the 10% and wouldn't benefit. That doesn't mean it's not a good product for many of the 90%.

        Yeah, that was my take on this too. This is for all the people who used to own VCRs forever blinking "12:00". Which, from my sample of friends' homes I've visited, was nearly all of them.

  • What they need to make is a thermostat that will smack the hand of anyone who thinks that turning the thermostat up to 95 will heat the house up faster than just setting it to the desired temperature.

    • What they need to make is a thermostat that will smack the hand of anyone who thinks that turning the thermostat up to 95 will heat the house up faster than just setting it to the desired temperature.

      Depends on the heating system and the thermostat. Two-stage gas furnaces and heat pumps may indeed warm up faster when there's a large delta between current temperature and desired temperature.

      • My second stage kicks in if the thermostat is set 2 degrees more than the current temperature (or if the furnace runs for a certain amount of time and the temperature hasn't reached the set-point).

      • by Zebedeu ( 739988 )

        Yes, same as my car. Setting a higher temperature delta increases the fan power which throws more cold/hot air around, but what I've noticed is that I usually forget to set it back once the interior reaches a comfortable temperature, and after a while I'm opening the windows because it's too cold/hot inside.

        I've now learned to simply let the car do its thing, except for very rare situations when I'm really uncomfortable.
        I like the idea of setting and forgetting. This thing seems to fit the bill, I'll have t

  • by Lumpy ( 12016 )

    This is the single most stupid idea ever. Humans are fickle about "comfort" and if you have more than 1 person there they will never be equal. the BEST way to save energy is to buy a setback thermostat that also has an outside temperature sensor so it can make smart decisions based on outside conditions and energy loss factor of the home. a better one will also have a windspeed measurement as a home will lose heat faster when the winter winds are blowing.

    Want to know what saved me a LOT of cash? I remo

    • by godrik ( 1287354 )

      "Want to know what saved me a LOT of cash? I removed the real thermostat and replaced it with temp sensors in each room and put a dummy one up that the wife can play with."

      That's EXACTLY what I need!

  • by Jethro ( 14165 )

    I have a programmable thermostat, but the thing is ancient and looks like a VCR from the '70s.

    I just went out and got e replacement for it, in part because this one's not SUPER flexible, and in part to help myself not be tempted to get a $250 thermostat, no matter how pretty it is.

  • 55* is enough to keep the pipes from freezing. I don't have the money to justify a cozy 68*-72*. Want it warmer? That's why they make clothes and blankets.
    • by adolf ( 21054 )

      Meh. 33 is enough to keeps the pipes warm. And if you're really being frugal with the layered clothing/blankets thing, it's often cheaper to set the taps to "slow drip" than it is to set the thermostat to "substantially warmer than freezing."

      Or just wrap heat tape on the pipes, and turn the furnace off. The water will still flow, the house will still be predictably fucking cold, and you'll still be able to bask in your frugality.

  • Problem Exists Between Thermostat and Floor?

    Like my darling bf who turn the heating on full and then keeps the door to the balcony open because "He needs fresh air" but "He does not want to sleep in the cold"?

    Who got to use our old fridge with the broken door to keep his beer in, turned down to minimum because the door was nowhere near tight. Instead of keeping the stock there and moving what he needs to our new low-energy fridge he turned it on full tilt and I did not notice because I do not use the beer f

  • I have a heat pump, and would like a reasonably priced smart heat pump thermostat. I can't use a standard programmable thermostat since if I tell it to go down to go down to 60 at night, then 68 shortly before I get up it will flip into Auxiliary Mode (actually more likely bump all the way up to Emergency Mode) and use the MUCH less efficient electrical backup systems. Heat pumps alone can be pretty efficient but often MUCH more gradual, needing a fair bit of lead time.

    A smart heat pump thermostat would p

    • I've been wondering why there are not super cheap ones out yet. Its not far above a LCD WATCH with a special cap that probably costs as much as the watch which cycles at different rates depending upon the temp. (I took my $17 unit apart and found the cap acting as a sensor.) Add a transistor switch and program the watch... I can get optical mice cheaper than these thermostats. programming them would only take a little bit of labor upfront-- these watches do a ton of stuff and have more buttons...for nothi

    • If you have any skill at all you should be able to put something together for less than $250 that'll do exactly what you need.

    • by necro81 ( 917438 )

      A smart heat pump thermostat would probably need external sensors for the outdoor temperature, and maybe even add things like wind speed, ambient heat from direct sunlight vs overcast, etc to determine when to start up the heat pump and stay only in the most efficient heat pump mode yet still get to the desired temperature at the desired time

      Sounds like you need the equivalent of a boiler reset control [taco-hvac.com] (PDF). It has a sensor for measuring outdoor temperature, and a sensor that measures the boiler exit te

  • Dis dude did it first: http://www.imdb.com/title/tt0389860/ [imdb.com]
  • Maybe they should ask Whirpool. We purchased an electric water heater by them about 5 years ago that learns your water usage pattern and then runs the heater accordingly.

    • I have a "smart" thermostat already. It cost me $60 at Lowe's. I set the temperatures I want for my weekly schedule (every day is programmable, with 4 different settings per day). Over the course of a week or two, it figures how long it typically takes to reach the desired temperature. So if I want it to go from 78 degrees during the day down to 74 degrees when I get home at 4, it will turn the AC at just the right time so that it reaches 74 degrees at 4pm. It's very nice.
  • So as I understand it, this is aimed at 1) people too dumb to program a programmable thermostat, and 2) people smart enough to give a shit.

    That market, traditionally, is government activists.

    Therefore, I should wait until it is free.

  • So, will Nest chop and haul wood for me too? I'd be all down with that.

  • Nest's fatal flaw is that one tends to adjust the thermostat in a reactionary manner, *after* you realize that you're too hot or cold. What's actually needed is an anticipatory algorithm. A case in point: the programmable thermostat in our house lets the temperature drop four degrees Celsius every night in the winter. It warms the house up again about half an hour before we get up. If I had a Nest, I would end up teaching it incorrectly -- it would assume that the time to heat the house was when I got out o
    • by Zebedeu ( 739988 )

      From what I understood, when you wake up and turn it on at 7:00 it's not learning "I should turn the heating on everyday at 7:00" but rather "the temperature should be X at 7:00".

      The system seems to also learn how long it takes to reach the desired temperature, so it can actually have your apartment warmed up just as you're waking up.

      This is, of course, my understanding. Reality may (and many times does) differ.

  • It might be a waste of energy to keep the temperature controlled when one is out (ex. at work). So if there was a button to toggle between away and home, then it could also work out when to not care about the temperature and when to switch the temperature control on again.
  • Intelligent HVAC systems are common. But this is doing it wrong.

    First, you need a return air duct temperature/humidity/carbon dioxide sensor. You need a similar sensor outside, to tell your control system what the outside weather is like. Then you need the ability to run the heating/AC fans without running the heating or compressor. That's the minimum. You'd also like to have a damper which can either take outside air or recirculate inside air, and a spray humidifier in the heating/cooling air duct.

    No

  • ...to get back the resources needed to produce it in energy? Electronics is horribly expensive to make, resource-wise. And this particular piece seems like it wasn't made to last.

  • None of the thermostats I've seen (not that I've looked that hard) have the one feature I want: a button that raises the set temperature by 2 degrees C for 30 minutes and then lowers is back to normal over the next hour. It would please the ladies who want an instant blast of heat while not annoying the chaps who don't want the house heated to tropical levels all day when it doesn't get turned back to normal.

  • I like that the US still uses Fahrenheit. If gives me great pleasure to type "105 f in c" in to Google to get the conversion.
    I don't mind if you don't get that. U F in C.

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