Ecobee3 Wi-Fi Thermostat with Remote Sensor, 1st Generation

!!May not be compatible with your system!!I really loved all the features this system offers, and the new 3.6 software allows great use of custom schedules, setting profiles, and added remote access. Unfortunately, I ran into the same problem others had (http://www.amazon.com/gp/customer-reviews/R1OITZU0HVT5IW/ref=cm_cr_pr_viewpnt?ie=UTF8&ASIN=B00NXRYUDA#R1OITZU0HVT5IW) involving the overheating of the main unit throwing off its temperature. The main purpose of the device (sensing your home's temperature at the base unit) is broken because it gets so hot under normal use the readings are worthless. Their engineers knew about the issue because the unit attempts to "calibrate" and add or subtract from the read temperature, which is worthless because it varies when the AC is triggered or not. Mine was always off by at least 4-5 degrees. The remote sensors work perfectly, though I had to hard reset one by removing its battery and shorting the terminals to drain capacitors.The support experience I had with this was typical, but sad for the price of this unit. I was escalated all the way up to the CEO, and never received acknowledgement that they knew about the problem or if there was a fix. I was met with typical disbelief (they did not believe me until I proved myself 3 times over), and troubleshooting that was not related to the issue (you need to duct tape the wall up). They even went as far as to attempt to confuse me by dumping logs in my face and reporting that it proved the unit was working properly. Unfortunate for them, I was very fluent in how the product worked and was able to parse the logs into a format to show unarguably that they were overlooking/misinterpreting the glaring evidence problem.While my experience is most likely not typical, I find it ridiculous that they allowed the possibility of any heat issues in a product this expensive. I attach photos that I sent to their support so you can clearly see I'm not bluffing. My recommendations are that you should try this product, and if it overheats, return it immediately and move on to something else.My contacts:Stuart LombardCEO, ecobeeMu SaleemSr. Manager, Content & Advocacy

Based on my extensive troubleshooting over the past few weeks with the Ecobee, I'm revising my review. A large section of this review is one of my most recent emails to their tech support because that email documents my findings which are still consistent with the intial review.In summary, I recommend this product with reservations. It has some really nice features, and many people seem to be having very good luck with it. In reading other reviews, I'm also seeing that a few people are seeing problems that are consistent with my findings and recommendations to Ecobee.THE GOOD: Attractive on the wall, can control basic functions from smartphone, works well for heating function. Remote sensors provide temperature and occupancy data for multiple rooms. Will overcool to adjust humidity.THE BAD: Temperature on main thermostat always reads 2-3 degrees high. It is not clear if the bias adjustment which is accessed via the menu applies to only the wall mounted sensor, or to the averaged temperature reading across all sensors. The wall mounted thermostat does not have many holes for ventilation, so temperature response is slow (side by side comparision with old mechanical thermostat). Not all functions are avalable via smartphone. No geo-fencing capability. Not possible to have different setpoints/ranges for specific sensors.THE REALLY BAD: When AC is running the thermostat itself gets hot which makes thermostat think the room is much hotter than it is. As a result, AC runs excessively, and thermostat does not control temperature. I "fixed" this by purchasing and installing a mechanical relay board. (more detailed info below)Here is a very recent email to Ecobee support (after numerous interactions troubleshooting the last few weeks).=================== Begin Email ===================I'm disappointed in your last email response saying that "we conclude there seems to be an air flow/draft influence affecting the t-stat sensor only." This is simply not supported by the data and several tests that we have both reviewed over the past few days.Primarily, I direct you to a test from two or three emails ago in which I manually jumpered at the furnace to start the AC. With the jumper in place, the Ecobee wall thermostat showed a drop in temperature as soon as the AC turned on. Without the jumper--when the Ecobee thermostat itself calls for cooling--the wall thermostat shows an INCREASE in temperature. This test by itself shows that air flow patterns are not an issue.Additionally, for the last several days of testing I've placed the remote sensor and old thermostat mounted on the wall within inches of the Ecobee thermostat. Both the old thermostat and remote sensor show that the temperature in that location immediately goes DOWN when the Ecobee calls for cooling. The Ecobee3 wall thermostat (both the original I purchased and replacement you sent) shows incorrectly that the temperature goes UP when the Ecobee calls for cooling. This divergence in temperature at the same location also support the conclusion that the thermostat itself is the issue.For an additional test on my theory that the thermostat electronics are overheating, today I added a mechanical relay board (Temco MRB-4) to isolate the Ecobee thermostat from the furnace/compressor. This relay board serves to remove the compressor contactor load from the thermostat. You can see from this afternoon's temperature trends, when the AC starts, the temperature reading of the wall thermostat drops as it should (exactly what happened when I manually jumpered the R-Y wires at the furnace). The thermostat FETs may be rated for 2 amps, but in practice the Ecobee wall thermostat overheats with a 0.25 amp load and shows an incorrectly high temperature.The reason this thermostat overheating problem is not seen during heating cycles is that the current draw for a heating call is near 0 amps. Still, the current draw of 0.25 amps for the AC contactor is well within acceptable range for residential AC equipment.There is absolutely no doubt that the Ecobee thermostat itself is getting hot (and producing inaccurate readings) when it turns on the AC compressor.I've spent significant time over the past several days testing, and most of my interactions with Ecobee support have been explaining basic testing results. I have an engineering degree and significant experience with process control instrumentation. I know how to interpret temperature readings and troubleshoot to identify cause & effect. I find it hard to believe that Ecobee support is having trouble interpreting these same results.I have read about other customers who have also been frustrated that their Ecobee3 didn't work and that Ecobee support kept insisting this was due to "air drafts". I have no interest in legal action personally, but to me this sounds like fertile grounds for a class action suit. Consumers who are also experiencing this issue will be receive higher cooling bills than they should. Adding more remote sensors would indeed help average the temperature readings and thus compensate for inaccurate readings at the wall thermostat--but this is passing along the expense of poor design to customers while generating even more revenue for Ecobee.At this point, I am going to research alternatives because I do not believe any further troubleshooting is going to be beneficial. If I do not find a better alternative, I may end up keeping the Ecobee thermostat since now with the addition of the MRB-4, that resolves the overheating problem. However, since I will have to use the bias adjustment to alter the wall thermostat reading, the remote sensor will not be of much use. This is really disappointing for a product that is so expensive.In summary, my recommendation is that Ecobee do the following:1. Review the design of the thermostat. There is not enough ventilation on the wall thermostat. There are only a few tiny holes on the bottom of the thermostat, and thus the thermostat has a slow response to changes in room temperature. Additionally, this lack of ventilation on the thermostat contributes to overheating of the thermostat itself leading to inaccurate temperature readings.2. Review the "complex temperature correction algorithms". They're not working.3. Consider reworking the unit to incorporate mechanical relays instead of FETs. I first became aware of mechanical relay boards while researching this problem and finding so many Nest owners have experienced FET failures and consequently had to replace their AC system. Replacing FETs with relays will make the wall thermostat bigger, but it will reduce issues with overheating and will greatly reduce the risk of AC system damage due to FET failure.4. Review support procedures and training. The tests I conducted and conclusions are fairly basic for anyone with control system experience. I will give Ecobee the benefit of the doubt that the support team is not knowledgeable, rather than suggest that they are intentionally providing incorrect and misleading information.5. IF there's a way to specify temperature bias for individual sensors, please let me know. I have seen with two different Ecobee thermostats that the remote sensor reads correctly, and the wall thermostat reads too high. It appears if I configure a bias adjustment via the wall thermostat, it affects all readings, and not just the wall thermostat. More sensors simply provide more averaging to lessen the effect of the single incorrect reading on the wall thermostat, but that's not a very good solution.5. Add geofencing capabilities to determine if users are home/away. There are not many thermostats that offer this, this but I have found that relying only on the wall mounted thermostat and remote sensor to detect home/away is not sufficient.=================== End of Email ===================Conclusion:All in all, this thermostat has potential, but there are some fundamental design flaws which cause incorrect temperature readings and cause the AC to run excessively. I've tested two Ecobee3 thermostats and they both exhibit the same characteristics, so this wasn't a fluke with a single defective unit. Although the Ecobee support team was responsive, it was frustrating having the same conversation with them repeatedly in which they insisted the incorrect temperature readings were being caused by air leaking from the wall cavity. I was able to prove this was not the case, and actually "fix" that issue by inserting a manual relay board to isolate the thermostat. That kind of troubleshooting and remediation would be beyond the technical capabilities of any consumer without a process control or engineering background. I will probably end up keeping the Ecobee thermostat with this workaround, simply because I don't see other alternatives on the market that have fewer problems.Since sensor readings are averaged together and the remote sensors seem to be more accurate than the wall unit, more remote sensors could theoretically help adjust for the measurement error of the wall thermostat. however the remote sensors aren't cheap, and in the end this is just a workaround for a design problem of the base unit.My take is that the remote temperature sensors are just a gimmick for 99% of the people who will receive them. If the main thermostat works, then the rest of the house is typically going to follow once the air ducts are balanced properly. The only benefit I personally see for the remote sensors is to let the unit know I'm still at home if I don't pass by the main wall unit periodically. Another vendor handles this with geofencing on the smart phone, and some other units don't have geofencing natively but it can be added with an iphone app. In the end, it's important to figure out how the extra features are actually going to work for YOUR lifestyle. A useful feature for one person is a gimmick or even a nuisance for another.I did not purchase the Nest because for a few reasons. First, Nest is touted as being so smart that users don't have to program it. My problem with that is that I have an irregular schedule and there's no way that Nest could just figure out my schedule. Reason two that I read several places that Nest has a 3 degree temperature swing--which is quite large. Almost every other thermostat maintains temperature +/- 1 degree. Any more than that is too noticeable. Most importantly, I did not want a Nest thermostat because I read about several people who have had FET failures which destroyed their AC systems. Older thermostats and many programmable thermostats use mechanical relays (like little light switches) that click on or click off. Mechanical relays are hardy little devices that are not prone to failure and they are super reliable at turning your system on or off. Some thermostats (like Nest and the new Ecobee3) use FETs which are like electronic/software "switches". They don't click, and when they fail, there's a good chance they will fail in the "on" position. This has apparently happened frequently with Nest thermostats and people have found that their AC compressor had been running for days/months nonstop and had seized up (which means at least a couple grand to replace it on top of all the electricity wasted in the meantime).