Nest Thermostat Review, Update #6

Update #5, Update #4, Update #3, Update #2, Update #1, Install

I didn’t expect to have another post so soon. But, the Nest experience continues to frustrate and baffle.

On the 3rd of January, I took the following screen shot of our basement schedule for heating:


Tonight (one day later on the 4th), we headed down to the basement to watch a recorded episode of AMCs Hell on Wheels and it was cold. Frak! What the…

The thermostat reported the temperature in the room was 62F. Seriously? It should have been about 66F at the time I looked.

I brought up the schedule and was disappointed (yet, not shocked given the other problems) to see:


All of the evening settings (except Monday?) had disappeared completely. I had not made the change. I don’t understand. I’m no artificial intelligence expert (my wife though has a CS Master’s degree with a specialty in it Smile), but I’m confident any learning algorithm I would write wouldn’t be this stupid and this broken.

If I were a competitor reading this, I’d be laughing just a little. Understand though – Nest still can make this work – don’t rest or expect them to just disappear so easily.

As Nest continues to be silent on these matters, I strongly recommend you not buy a Nest thermostat. It’s an undone expensive piece of hardware, that while shiny and new, isn’t ready for the duties it claims to have mastered.

Update: Janurary 13, 2012 – This happened again. The schedule for Saturday and Sunday was modified to entirely remove the evening set points.  Nest support recommended that I turn off the “learning” feature of the thermostat yesterday and I hadn’t done that yet. But now I will and see if it happens regardless.


  1. Thanks for the detailed review. I was about to pull the trigger and order two of them. After reading your report I think I will wait until they debugged those things and rely on good old human intelligence rather than artificial one for a little longer (especially at a $550.- price tag)

  2. I had a similar experience tonight: all my morning setpoints were still present, but every one of my late-morning setpoints had disappeared.

    And then something even freakier: I watched as (in my browser) the Nest temperature ticked down, second by second – all the way down to 50 degrees! I thought maybe this was a web problem, so I ran downstairs and sure enough the Nest had dropped to 50. So I turned the ring back to 72… and watched it slowly tick down again.

    I then went back to the browser, and clicked the up arrow about 12 times… and the Nest slowly climbed all the way to 90 degrees (!) then started ticking down again. When it hit 72 I closed the browser tab on a hunch, and this solved the problem. Clearly the website had a bug which was confusing my Nest hardware.

    Regarding temperature accuracy, however, I am delighted with the Nest. I had the opposite experience of some here: my Honeywell was 3-4 degrees off while my Nest is spot-on, and consistent.

    Virtually every complaint listed here, including the desire for pre-heating and for historical data availability, is solvable via software, so I remain optimistic and enthusiastic about the product overall.

  3. That’s exactly what happened to me! Night settings disappeared on about Day 12!
    And that’s when I reset my schedule and paused learning. Been just fine since.

  4. WOW, I’m glad I googled for experiences first!

    I just received an alert from Nest that I could purchase one as I was on thier waiting list. I am certainly not going to buy one now. I too was hoping for energy/cost savings with the snappy advertised features but since they don’t work very well I can only see myself as frustrated.

    Thank you for the reviews and comments! you just saved me $250 which I can certainly use other places in my home. :)

  5. Perhaps that is what happened to my NEST…it lost it’s night time settings and that is the reason it got so cold….

  6. I’m trying to connect to NEST via my Iphone and it times out stating “Nest can’t control your therostat because it can’t connect to”.

    What gives now??

    1. Well, remember that the Nest is in beta. :) (Well, at least the web site, which is what the app uses for its UI). If you can hit the from a web browser on your computer yet the iPhone can’t (using the same network), that’s bizarre. Can you hit the web site from Safari directly?

    2. Well, remember that the Nest is in beta. :) (Well, at least the web site, which is what the app uses for its UI). If you can hit the from a web browser on your computer yet the iPhone can’t (using the same network), that’s bizarre. Can you hit the web site from Safari directly?

  7. Thanks for your detailed reviews and updates. I installed my Nest on 1/1 having received it a couple of weeks earlier. I waited because of concerns I had that the holiday schedule would throw off the ‘learning’ aspect of the unit. A fear which appears justified.

    Regarding temperature accuracy – I initially had the Nest set for the same temperature level as my previous thermostat, however, the house seemed noticeably colder. I have not tested the accuracy of Nest’s temp measurement, but I strongly suspect that it is off (higher than actual). While this is disappointing, it is not a deal-breaker.

    Other issue – Even though my Nest is set to run the fan ‘automatically’, it seems to run the furnace fan all of the time. I initially considered the possibility that this was an ‘intelligent’ choice made by Nest to maintain an even temp within the house, but based on the comment thread I doubt that Nest is smart enough (at least currently) to make this decision. I sent a support email to Nest yesterday early AM and have not even received an acknowledgement. I have sent another support request, but am already concerned about customer support.

    It is very disappointing to read the comments about Nest not anticipating temperature preferences. Given that I had to enter my zip code and that it calculates time to temp, I cannot imagine why it could not (at least in the near future) be made to do so.

    I echo the recommendation to hold off until further product development is made.

    1. @Jon H — does your Nest get power through the “C” wire? Apparently, if it can’t, it needs to cycle the system to get power through the “Rh” connections, and according to some, that doesn’t work very well.

      For support, I didn’t get a response when I sent a direct e-mail. When I used their support “form” I did get a response about 6 hours later.

  8. I have found numerous glitches in the web based schedule editor, in particular when using Chrome with Large fonts specified. The worst one is that occasionally when I add a new point it spontaneously disappears up to a minute later. A quick check with Firefox (with large fonts) also showed some problems.

    I reported several of these to Nest Customer Support and they have been very good at responding. At one point they wanted to get on line somehow and watch what I was doing in real time, but I didn’t take advantage of that. Note that the schedule editor is marked as Beta.

    One very annoying feature of the schedule editor: after initial learning, the nightly “turn down” points were all around 12:15 AM. I wanted to move them to 11:15 PM. The web editor will not allow it. You need to delete and re-add all the points. Their customer support response was basically “you can’t do that”. (It’s easy to do it on the actual thermostat, except for Sunday/Monday.)

  9. I sent a suggestion to Nest customer support for improvements like those discussed here, and got this response: “…please see our policy on unsolicited ideas.” at

    Nest’s Policy Regarding Unsolicited Idea Submissions

    Please do not submit to us any unsolicited ideas for products, product improvements, product technologies, product names, advertising strategies, slogans, songs, jingles, etc. (“submissions”) regardless of whether you think they are new or old, good or bad, original or unoriginal. Just don’t send them, in any form, to us or to any of our employees. The reason for this policy is to avoid potential disputes or misunderstandings regarding intellectual property ownership. …

    The last time I got this kind of response was from IBM in the late 60s.

  10. Hi Aaron,

    Well, after having the Nest for more than a week now, I have to agree with your earlier assessment in update #1 – the Nest learning algorithm is seriously broken.

    After only 6 days of use, the Nest proudly announced on the LCD that it had learned my schedule. Seriously – after just 6 days of use it claimed it knew how every day in my schedule should be. And apparently it meant it, because I’ve had lots of frustration with the schedules I set up mysteriously changing – end times disappearing from sets of days, etc. The Nest really thinks it knows what is best for me and it keeps removing the manually settings I make on the schedule, regardless of whether it’s set via the web interface, the iOS app, or via the Nest LCD itself.

    At this point, I think I’m going to turn of the learning feature and stick with a manual set schedule along with the ability to remotely adjust the temp, but that that’s a far cry from the expectation I had when originally buying this thing.

    Based on Mark’s comment above regarding Nest not wanting any suggestions, that’s very sad to hear. I’m now very tempted to just write my own AI to control and monitor the Nest via the web interface. Then I could have email alerts sent to me if the schedule mysteriously changes, calculate my own trending on how long it takes to heat the place and hopefully eventually have something that might get closer to the true potential for what the Nest *should* be able to do already. The hardware has all the support there – it’s the software from Nest that is unfortunately severely lacking and in many cases just plain broken.

  11. Mark – actually the last time I saw such an unsolicited idea policy was from Apple:

    Which is another reason most modern tech companies host public forums for community support and product suggestions; it’s hard to argue your brilliant idea is somehow protected if you submit it in a public forum (and of course the forums haveT’s and C’s to protect the company)

  12. Aaron – Thanks for the feedback. Power is provided through the Rh wire, not the C wire. If this is a problem for Nest, chaulk that up to a further disappointment. My old thermo did not have an issue nor would any unit you would pick up at a home improvement store (I would imagine).

    Regarding my submissions, they were both placed through the support form on which, apparently, does not bother to send an acknowledgement of your request.

  13. I’ve had a good experience with my Nest scheduling so far. Though, I have a pretty regular and steady schedule.

    Something about the Unsolicited Ideas mention above. That doesn’t sound like Nest isn’t willing to consider feedback from their customers, they just want to protect themselves from a lawsuit. As mentioned above, they don’t have a forum to process idea submissions, which are very different than feedback for legal purposes.

    I still love the simple interface and sleek design. It’s sad to hear that other people are having trouble with a device that I’m in love with. (In love with a thermostat? Maybe there’s something wrong with me.

  14. Nest may not have a forum, but I have seen some (mildly) critical comments on their blog (see website). I wonder just how critical a comment they’ll allow?

  15. Last night before going to bed I noticed that my Nest had not set back the temperature. I checked the learning schedule (on the Nest itself) and found that for 5 of the 7 days, the nighttime setback point was simply gone.

    My Nest has been in training for over 10 days. A simple schedule had been established: 69 degrees each morning about 63 degrees each evening at 11:15. About 4 days ago I made some manual changes to the schedule using the web browser, changing the temperatures at the 11:15 time by a few degrees. I am absolutely sure that when I last looked at the web display, there were “orange circles” on the schedule for all 7 nights. Five of them simply disappeared over the last few days, during which I made no changes to the device at all.

  16. I’m glad I found this blog linked back to the NEST site before I had an opportunity to buy one. I continue to be interested in the product but had concerns regarding setback, anticipation, and overshoot control (ability to alter CPS settings). I sent emails to NEST but got no responses. It would seem based on the info here that the unit indeed has issues in these areas. I think I’ll be waiting until they get the firmware upgraded.

  17. Aaron,

    So glad I found your blog. I only wish I’d found it before I plunked down my $250 for the not-ready-for-prime-time Nest. I’ve had all the problems you and others have been mentioning — my manual schedule entries mysteriously disappearing, Nest failing to turn on at scheduled times, inaccurate temperature sensing, Nest’s inability to schedule a target-heat-at-target-time (as opposed to turn-on-at-preset-time), etc. I hope that by continuing to pester Nest support with our questions and criticisms we can get the company to improve the software. It sounds as if it should all be do-able. BTW, I loved your detailed account of your installation. It’s so much better than Nest’s own. I just wish I’d read it first, as well. Keep up the good work and the updates.

    1. Thanks for the kind words Marc! My goal is to educate those who have not yet decided to drop the cash for one or more of these thermostats, so that they can make a more informed decision while the Nest thermostat is not ready for prime-time.

  18. Status update on the fan running continuously issue – I contacted support by phone and got right through to a support rep who took me through troubleshooting the Nest. It turns out that there was apparently something wrong with the base, as whatever wire was contacted to the “G” port would be activated. It turns out that I didn’t really need the “G” wire to be connected on a gas furnace if I only wanted the fan to run when the heat is on. Therefore, I was able to disconnect it while they sent me a new unit which arrived already today.

    I installed it and it appears to be running properly. I guess that the use of the Rc line for a trickle charge is not an issue with a gas forced air system. Hopefully this unit will continue to work properly and Nest will refine their software to accomplish what they more-or-less advertised.

    Side note – interestingly, Nest support contacted me about my website submitted requests approx. 10 min after I got off the phone with the support call I initiated. Kind of an interesting coincidence.

  19. The user community really should set up a NEST forum. Between bug discovery, behavior questions, tips/tricks, and now the API there is a lot going on and it’s spread in many places. That being said, I have a question regarding NEST behavior on recovery from a setback. How long does it wait before engaging 2nd stage heat? The NEST website explains how it should work, but I’d like to know what peoples experience is with 2nd stage as related to heat pumps and resistive electric 2nd stage. Ability to have good control over 2nd stage I believe is critical to achieving energy savings with heat pumps. It would appear nest is headed in the right direction in this area but without a detailed technical guide or installers manual available, it’s not clear how the function (and the related aux lockout) functions work. Does lockout use the web interface to get weather data?

  20. My two Nest thermostats worked well for several days…then the fan started running continuously on the one attached to my older furnace. I called support and they had me run several tests, then told me there was a short in the Nest base so they would send me a new one. The guy took down my shipping info, but then after being put on hold so he could check with their tech department, he came back on and told me they couldn’t help me after all. He said they’d gotten several complaints like this, and realized that old systems like mine have voltage spikes from the furnace transformer. That fuses the circuit, so if they sent me a new one it would just happen again. Now I have to decide: get a refund, or spent $ on replacing the transformer and hope that really does solve the problem.

  21. I’ve got two Nests – one for my downstairs zone and one for upstairs. I installed them on New Year’s Eve, so with a late night and a holiday the next day it threw the initial schedule learning for a loop (I was surprised that it claimed to have learned my schedule after only one weekend day and one weekday – seems a little presumptuous that every owner works a standard work week). Since this initial schedule was not the norm, I set up a correct schedule manually via the Nest web site.

    Since then, things have been working fairly well. I’ve had a couple of instances where the learning slipped up and made a wacky change, forgot a set point, etc. but I decided to persevere, especially given the relatively frequent software updates. This Monday was Presidents’ Day, and so my schedule was different from the last several weeks; I adjusted the downstairs thermostat so it was running at a higher heating set point for the day. The following day I checked the Nest status on my way to work via the iPhone app, and was surprised to see the heating was running downstairs at the temperature I’d set the previous day. I checked the schedule, and saw that Nest had “learned” that I wanted my heating turned up to 68 degrees during the day every day of the week! This was after just one day of a modified schedule, and for a holiday too. You’d think Nest, being web-connected, would understand holiday dates and ignore any unusual activity on those days. Even without that, it shouldn’t change my entire weekday schedule just because of one day’s temperature change – I thought it was supposed to detect behavioral patterns over time.

    So, I decided my perseverance with schedule learning wasn’t worth the hassle that came with it; schedule learning is now paused on both my Nests. I’ve fixed the schedule manually, and all is now well. As an attractive, programmable and web-connected thermostat it’s still a great albeit pricey piece of equipment – programming is especially convenient and far quicker than thermostats I’ve owned before. The schedule learning just appears to be broken and/or misguided – it simply doesn’t work in its current form, and at best requires a lot of babysitting. As a learner, it’s definitely more like a toddler (requiring constant correction) than the college math whiz Nest portray it as. I’m not going to bother until it grows up a bit.

    Here’s what I would suggest to Nest; 1) have schedule learning monitor the owner’s habits for 2 weeks – don’t rush the learning process; 2) provide an option to stick to the learned schedule once that 2-week period is up, so it amounts to an easy initial setup method rather than an ongoing learning process; 3) consider monitoring user habits compared to their schedule, and notify them if it looks like the two are out of whack – give a simple yes/no option to update to the new schedule, possibly even showing it too them first via email, app notification, etc. instead of assuming they want it applied; 4) if learning does indeed stay as an ongoing process, fix the algorithm so it gives appropriate weighting to rare temperature changes; 5) have the Nest understand holidays, and give the option to exclude them from learning (or just do that anyway by default).

    My other issue is Auto Away. It takes 4+ hours to turn on, if it ever turns on at all, and sometimes turns off unexpectedly. I think they could do something better and potentially simpler here than the current ; look for my family’s iPhones on the Wi-Fi network for example, and if it doesn’t see them switch to Away mode; integrate with my security system which is always armed Away when I’m out of the house. These two options would switch it to Away almost immediately, rather than continuing to run my heating for 4 hours after I leave. Again, this is too much babysitting to keep track of whether Auto Away has kicked in, and also means I have to adjust my schedule so it turns down the heat around about the time I leave the house so I’m not burning fuel for 4 extra hours every day. This seems counter-productive; why not have a more reliable approach to detecting whether I’m away, and allow me just to set daytime and nighttime temperatures – if that were the case, it would turn the heating down whenever I leave the house, and whenever I came back it would go back to an appropriate temperature for the time of day. I shouldn’t have to schedule (or have the Nest learn) a heating set point change around the time I leave the house – it should *know* when I’ve left the house the moment it happens, and switch to an away temp immediately.

    As you can probably tell, I’m on the verge of disabling Auto Away too. As soon as Nest has an API, I’ll be programming to it to switch Away mode on/off based on my home security system arming status (the system sends email notifications of arming events, so I can switch the Nest status based on those assuming I can figure out how to intercept them, such as via IMAP). With your reverse-engineered API I might be able to do that now, even before a supported version comes along from Nest.

    So, I agree that some of the features Nest is really pushing are not ready for prime time. They’ve gone with a complex approach for the schedule learning and auto-away (multiple sensors, sophisticated algorithms, etc.) in an attempt to keep things simple for the user. This would be great if they worked well, which today they do not. I think the approaches they’ve used under the hood to solve these problems are overly complicated as highlighted by the current problems with them, and it seems to me they could be doing something simpler such as my suggestions above. Apart from these gripes I do really like my Nests, but users who aren’t as patient with new technology as I am must be getting frustrated with the quirks, and potentially even seeing their heating bills going up instead of down.

    1. Thanks for the very thoughtful comment Marcow. I still don’t understand auto away and it’s triggers. I’d expect some consistency day to day, but it’s not.

  22. Me too – it’s very unpredictable. I do have a couple of small cats in the house, but given the location of my Nests I think the cats would be far below its field of view at all times.

    Next week I’m hoping to have time to play with your Nest client code. I should be able to switch Nest to/from Away mode based on whether my iPhone is visible on my Wi-Fi network (assuming that’s reliable and that my iPhone really is connected to the Wi-Fi network all the time when I’m at home – don’t know if it ever disconnects to save power), or based on email alerts from my security system. If I can get this working, then it would beat Auto Away hands-down in my opinion!

  23. That power stealing of the Nest was a real problem for me. We did nor know it for a few weeks but the Nest’s power stealing was pulsing the outside compressor on and off (my A/C tech “oh, that’s not good when I played an audio of it”). He determined that the transformer in the Rheem compressor was not capable of matching the Nest’s power demands (he said the unit outside was 24 V/ 40 VA and the Nest would need 24 V/75 VA) and was tripping the unit on and off. Had this been a roof mount like in many condos in FL it would have gone undetected until the unit failed. I spent my money of two tech visits to figure out the problem, none of the Nest solutions on the website worked and my AC company was not impressed and did not like the thing and noticed it could not manage the newer high efficiency units they sell now.
    The really stupid thing, and my real problem with Nest Labs, is that Nest Labs refuses to take back the unit since it is beyond the “30-day” return window! They are already hiding behind “policy” when dealing with their early adopters. Basically Nest Labs is an arrogant little company with it’s head in the sand fooling around with people’s very expensive HVAC systems. Definitely a beta product. Stay away.

Comments are closed.