If you are a typical homeowner, you spend the greater part of your home energy budget on heating, cooling, or both.  Regardless of whether your primary source of that energy is gas or electric from your local utility, fuel oil, propane, or other form of purchased energy, wouldn't it be great to pare down that cost a bit?  Your thermostat might be an easy way to start saving.  Up until the last few years, most thermostats fell into two categories; there was the old fashioned manual, or the programmable thermostat.  The old fashioned manual thermostats could be as basic as a mechanical  coil and mercury model or a digital thermometer model, but the functionality was the same, which was one temperature setting for cooling or heating.  If you want a different comfort setting, you get up and change the it by hand.  Programmable thermostats are a step up from that.  Most allow for weekly schedules, with different day and night settings, and even different weekend and holiday settings.  This allows for more economical settings while the house is unoccupied, with cool-down or warm-up when the home is re-occupied.  Some even have WiFi capability for remote setting and monitoring.  So called 'smart' thermostats are relatively new, and have only been out for the last several years.  They are quite pricey when compared to even the programmable thermostats.  Are they worth the extra money?  Read on for one answer to that question.

 

How Ecobee3 Was Selected

Before purchasing a smart thermostat, I took a long look at all the models I could find.  Before shelling out more than $200 on a thermostat, I wanted to make sure I selected the one that best fit my needs and one that I was confident would be worth the money.  Criteria that were important to me were true energy savings, flexibility, ease of use, and compatibility with my smart-home ecosystem of choice.

• Energy Savings:  Will the new thermostat pay for itself?  Will it save enough money to justify the time and effort I put into installing, configuring, and maintaining it?  A total value proposition is more important than a lower cost model.
• Flexibility:  I have a relatively unusual heating system in my HVAC setup.  My home is about 20 years old, which pre-dates smart thermostat installations.  My current HVAC components are likely near end of useful life, so will a new smart thermostat work for new equipment, or will I have to start over?
• Ease of Use:  I'm an engineer at heart, and enjoy fiddling with things to optimize their usefulness.  My family does not.  They want to be able to easily adjust the temperature if they are not comfortable, without the need for an instruction manual.  Does it 'learn' from my usage, or does it requre extensive programming?
• Smart Home Compatability:  My ecosystem of choice is currently Wink.  I also have an Amazon Echo, an IFTTT account, and various other smart-home gadgetry.  Does it fit in easily, or does it require a lot of kludgey work-around?

The models I researched were the Nest, Ecobee 3, Honeywell WiFi, and Emerson Sensi.  At the time I made my purchase, there appeared to be the best available models out there.  At first glance, all of these models seemed to do about the same thing. with the main differences being style and manner of user interface.  Upon closer inspection the differences became more noticeable.  A quick overview of these thermostats, with their pros and cons, will illustrate why I chose the Ecobee 3 over the competition.

Nest (3rd generation):  I was immediately attracted to the Nest first, not only because of it's iconic shape and user interface, but also because it was touted as a 'learning' thermostat.  These features are indeed impressive, and helps to set it apart.  It was the first one on the scene as far as truly 'smart' thermostats are concerned, and it shows in product maturity.  At the time of this writing, the Nest is in it's third generation being shipped, and it appears customer feedback was strongly considered in the improvements to the later generations.  Nest is a Google owned company, and produced it's first Nest model back in 2011.  The current model (gen. 3) lists for $249, but has been seen as low as $199.  Nest claims to pay for itself within two years use.  Pluses for this thermostat include easy installation and setup.  To program the Nest, simply follow your daily routine, setting the temperature manually as you go.  After a week or so of this, the nest learns your daily habits and comfort settings and builds a schedule to follow.  This works pretty well for most households, but has drawn occasional complaints among those that don't have a 'daily routine'.  Display can be set to different colors or default information settings.  Negatives include perceived internet security issues, which Nest claims to have resolved, and has had some outages related to software updates, which were quickly resolved.  Probably the biggest issue that many users have complained about is the 3 degree temperature delta that triggers the heating or cooling equipment to come on.  It is not user changeable, and for many, this is a deal breaker.  some say the user interface is a little too simplistic, offering less tinkering with the detailed settings that many like to do.

 

Ecobee3:  Ecobee is a relatively newer player, and is engineered and manufactured by a Canadian company.  They have done well establishing themselves, fighting an uphill battle against the huge thermostat maker Honeywell, and the marketing might one would expect from the Google owned Nest.  Despite being lesser known, they have grown quickly, and have an enthusiastic fan base (as if one could have fans for thermostats - pun fully intended).  Among thermostats, the Ecobee 3 also has an iconic look; it is kind of like a squared off hockey puck, in size and color.  It is kind of like Henry Ford's famous saying about the Model T, "You can have it painted in any color you want, as long as it is black."  One odd thing though; the base is white, which you usually don't see once it is installed, but the trim ring is white (only used if the previous thermostat left a larger hole in the wall).  For most, they will just see the black hockey puck.  This thermostat had some predecessors manufactured by Ecobee, but this is the first with this level of sophistication.  The programming is not as simple as the Nest, but it does immediately settle your activity into home or away, and daytime and nighttime temperature zones.  This is where this model really shines; not only does it have remote wireless sensors you can place anywhere in the house, it takes them into account as it sets the temperature for the entire house.  If you have one room that is always a little warmer or cooler than the rest, place a sensor in there and take it into account.  The sensors also perform an additional feature that cannot be under-valued; they detect occupancy.  Why is this valuable?  Let's say that you work at home during the day, mostly in a home office.  The thermostat detects this and sets the temperature to the 'occupied' setting even though the time of day would ordinarily dictate that the home should be 'unoccupied'.  Even better, if you are spending your time mostly in your home office, the sensor there tells the Ecobee 3 that the rest of the house is unoccupied, and only occupied in the one room, so it heats and cools to the 'occupied' temperature using just that rooms sensor.  This is called the 'follow me' setting.  Pluses for this model are the multiple sensors, granularity of nearly any setting, ease of use, and style.  Negatives are lack of flexibility in the 'home' screen, and inability to connect to the thermostat directly with the mobile apps - this must be accomplished through both the mobile and thermostat connecting back to Ecobee's servers.

 

 Honeywell WiFi (Model RTH9580):  This is a solid learning thermostat with many great features and huge compatibility when it comes to home automation ecosystems.  Honeywell has been around a long time, much like Emerson, and they know their temperature controls.  This is a larger thermostat when compared to the others, but it does have a large, bright, configurable display that will appeal to many.  The frame is silver and kind of wide.  The list price is $225, but has been seen as low as $180.  This thermostat, like the others inthis group is meant to replace your aging or defective thermostat, while updating the features and capabilities.  This thermostat is completely configurable either from the large display or via the mobile app.  This model also has published a set of API's that make it super compatible with more than any other thermostat in this group.  If you like to tinker with settings and connectivity, this might be the thermostat for you.  Pluses are the more granular configurability, the wealth of inter-operability options, and the moderate cost.  Negatives for this model include lack of support for installations with no 'C' wire, and overly bright display.

 

 

 

Emerson Sensi:  While this model was the lowest cost of any in this group, it performed the majority of the functions most would purchase a next generation thermostat for.  This model lists for $129.  It has very simple programming, albeit no true 'learning' features, and is a super compatible replacement to most heating and cooling systems default thermostat.  This model is not a learning thermostat per se, however, with home automation tools, it can be made to detect whether your home is occupied or not, and change the program accordingly.  Technically, this does not meet the requirements that distinguish a 'smart' thermostat from one that is simply programmable, but it still made the list due to price, features, simplicity of use, and the large lit display.  Additionally, the ability to adapt to the outside weather, and the integration with a mobile app, one could see that this thermostat is an update away from what other thermostats would call 'learning' ability.  Like the Nest and Ecobee 3, this model works with a pretty wide list of equipment, but doe not have the ability to control extra humidifiers, dehumidifiers, or ventilators.  The display is somewhat larger than others in this list, but the display is neat and uncluttered.  It has a back-lit LCD display that stays lit.  Like the Ecobee 3, it does require access to the internet for both the mobile and the thermostat to change the temperature remotely.  Pluses are the low price (seen as low as $92), easy installation (does not require a 'C' wire), and fast setup.  Negatives include a kind of a plain display, and lack of advanced 'smart' features.

 

 

 

	Ecobee3	Emerson Sensi	Honeywell WiFi (RTH9580)	Nest
Price	$249 1-pack of extra sensors $79	$129	$225	$249
Annual Fees	none	none	none	none
WiFi	Yes	Yes	Yes	Yes
Equipment under control	Heating, Cooling, Heat Pump, ventilator, humidifier, dehumidifier	Heating, Cooling, Heat Pump	Heating, Cooling, Heat Pump	Heating, Cooling, Heat Pump, ventilator, humidifier, dehumidifier
Smart-home Ecosystems	Amazon Echo, Apple HomeKit, IFTTT, Samsung SmartThings, Wink	Amazon Echo, Wink	Amazon Echo, Apple HomeKit, Samsung SmartThings, Lowes IRIS, IFTTT, Wink, and many others	Google Home, Nest Smoke/CO2 Alarms, Wink
Mobile App	iOS, Android	iOS, Android	iOS, Android	iOS, Android
Wireless Remote Temperature Sensors	Yes, up to 32	none	none	none
Geo-fencing	Not natively. IFTTT required	none	Not natively, IFTTT required	Yes
Reporting	Yes	none	none	Yes
Historical data retention	15 months	none	none	10 days
Claimed energy savings	23% average savings on heating and cooling	Up to 30% when using their pre-defined schedule	Claim of at least $53 annual savings, however must use an online calculator to determine savings, based on location, fuel cost, and other factors	10-12% heating, 15% cooling
Illuminated display	Yes, displays inside temperature and outdoor weather; proximity sensor updates display to control settings when approached	Yes	Yes, can change color to match decor	Yes, can be configured to display analog or digital clock or the temperature, proximity sensor updates to control settings when user present

 

In short, there were three factors that put my choice, the Ecobee3 over the top for my selection.  All of the thermostats claimed in their own ways that I was assured of enough savings in two years to pay for the thermostat, and since I planned on installing it myself, there were no further costs other than my time.  So, the lower priced thermostats would have a shorter payoff, but they all eventually paid for themselves.  So, Energy Efficiency was a wash in my decision.  

Next, the two thermostats that showed the greatest flexibility among systems were the Ecobee3, the Sensi, and the Nest.  The Honeywell WiFi thermostat, at the time I researched them for purchase, did not appear to be able to deal with the lack of the 'C' wire.  The other three thermostats had solutions in place to deal with the issue.  The Ecobee3 actually ships with an adapter that allows power to be delivered across the existing thermostat cabling if there is no 'C' wire present (more on this below).  In my case, the existing thermostat cabling did not require a 'C' wire but the I had extra unused wires in the cable itself, so this became a non-issue.  So Flexibility gained a point for the Nest and the Ecobee3 (see chart above for compatible equipment).

For Ease of Use, the Nest could not be easier.  The Ecobee3 was a close second.  The other two did not come close.  Voice commands, and mobile apps were easy and intuitive, and they mimicked the behavior of the actual thermostat.

Smart Home Compatibility was a wash across these four thermostats, as they were already compatible with the ecosystem of choice for me.  However, if I were undecided as to the ecosystem I were to choose today, I would have to lean toward the Honeywell WiFi thermostat.  It had too many compatible systems to name here in limited space.

As I compared these thermostats, I realized there were a few more factors I found to be important, that I wouldn't have considered without a lot of reading actual user experiences, Q & A forums, and FAQ's from the manufacturers web sites.  First, the unchangeable three degree gap before equipment is engaged is a deal breaker for me.  My old digital thermostat actually had a small switch inside where this could be set, and from personal experience, 3 degrees is too much.  There are dozens of posts in multiple forums where users agree.  Next, and this is related to the first point, there needs to be the ability to adjust settings and schedules manually from time to time.  Not allowing this adds a level of frustration for those of us that like to 'fine tune' things.  Lastly, I really like the idea of measuring the temperature all over the house, or at least from more than one location.  Most of us live in homes where the thermostat was placed into a location not of our choosing, often a hallway or other common area you don't spend most of your time in.  Why not measure the temperature where you actually spend your time.  The Ecobee3 is the only one that has this capability, and it ships with both the internal sensor within the thermostat itself, and one extra external one.  Additional remote sensors are about $79 for two.  Considering all these factors, the Ecobee3 was the clear choice for me.

  

Installation

Even with a somewhat unconventional system such as mine, installation went pretty smoothly.  As mentioned above, my old conventional thermostat did not utilize the 'C' wire.  It had a battery that supplied power to the thermostat itself.  The Ecobee3 is hard wired for power, and therefore does not contain a battery.  Hard wired for power means that the power to run the thermostat comes from the heating/cooling systems itself.  Typically it is in the form of 24VAC.  The reason the 'C' wire is needed is that it acts as a 'common' return path to the heating/cooling system.  The other wires there are to switch on the heat/cooling/fan components, and they only carry power until the circuit is closed.  This would cause an interruption to the power of the thermostat, causing everything to shut down, defeating the purpose of having it in the first place.  Ecobee came up with a way to inject the power into just the four wires, so that the thermostat stays powered up constantly.  The adapter kit comes with the thermostat and the directions are easy to follow.  In my case, I did not need to use the adapter kit, as I had four other unused wires in my cable to convert into a 'C' cable.  I probably made it more difficult than it needed to be - I took a photo of the original wiring, than matched it up to the Ecobee3's wall plate just to make sure it was all wired correctly.  I then had to figure out where the 'C' connection was in my hybrid heating/cooling system so that I could connect it at the far end.  That turned out to be the hardest part, because the relatively obscure model air handler was hard to get to, had a panel that couldn't be completely removed once it was installed, and it appears I had some shoddy repair work done in the past, and the technician didn't use the conventionally color coded wires in two separate cut and splices that didn't need to be there.  Long story short, most installations will not have this issue.  I could have gone the easiest way and used the four wire adapter.  Since I had the extra wires in the cable going to my thermostat, I figured I would do it the 'right' way instead.  I'm glad I did - it allowed me to clean up some shoddy wiring in my air handler.

OK, here is where we give the obligatory warning.

 

WARNING This article is not meant to be a set of instructions for installation of electrical circuitry, devices, or any kind of guide for working with wiring of any kind,  Green4Geeks is not responsible for any damage, injuries, or death resulting from attempting to replicate what is depicted here.  Green4Geeks recommends using a qualified electrician or HVAC contractor to perform similar installations for yourself.

 

 

I'm adding the installation details for my particular brand of air handler just in case someone else has the same thing and needs to do a 'C' wire install.  If you don't have this configuration, please skip this section.  My system uses recirculating hot water from the homes water heater to provide heat in a coil assembly within the air handler.  This system is difficult to find parts for, and from what I have learned, is common in some hotels, apartments, and condos.  Why this was installed in a single family, stand-alone home is beyond me.  The air handler is an Aquatherm model 60HB08, with a FirstCo controller board, model # CB201.  Below is a photo of the control board:

Please note that the spade lugs labeled 'COM' are those that are to be connected to the 'C' wire at the air handler end.  In my case, since both spade lugs already had attachments, I simply spliced in a wire nut onto one of the wires coming off the existing connection (lower part of photo).

OK, enough about my Aquatherm woes; on to the fun part, the thermostat install!  The first thing to do is to label the wires coming off your old thermostat.  Simply remove the cover, and write down what you see - if there is a red wire, see what the terminal it is connected to, and write it down.  Or, do what I did and just take a few pictures of it.  You should also note if there is a jumper wire between any of the terminals.  As you can see in the pictures from my old thermostat (below), there is a jumper made from a piece of bare copper wire between the two terminals labelled 'RH' and 'RC'.

 Once you have labelled the wires, or at least documented them, it is time to get rid of that old thermostat once and for all!  Disconnect the wires, and preserve as much of the old wire as possible.  In other words, dont simply cut the wires, instead, carefully unscrew, unclip, or otherwise unfasten the wires from the old thermostat.  Full disclosure here:  I kept my old thermostat, and still do, in the case that the new one should fail, so that I have some sort of backup while dealing with repairs of replacement of the new one at some point in the future.

Installing the Ecobee3 is pretty easy.  First, install the backplate using the two included screws.  A lot of older thermostats are kind of large, and depending upon the age of the home, may have had old paint or a large drywall hole that was covered by the older, larger thermostat.  For that, Ecobee includes a wall plate that is larger than the thermostat to cover the old work.  To me, the larger plate really takes away the simple clean look of the thermostat.  It is also white, which is a stark contrast with the black body of the Ecobee3.  The trim plate is paintable, so you could match it to your wall color, but if you are going to that much trouble, you might as well just patch and paint the wall itself.  Fortunately, I did not have to do a drywall patch, and I had some of the paint left over that was used to paint the wall originally, so I just touched up a bit.  Below is the new thermostat base mounted to the wall.  Note the built in bubble level that assures you have it mounted straight up and down.

 At this point, all there is left to do for the physical installation is insert the wires into the same labelled connectors as the old thermostat, pop on the face-plate, and move on to the the testing and configuration phase.  

 

Setup

Setting up the thermostat is really simple.  Just follow the prompts, and it is pretty hard to go wrong.  If you are new to this kind of thing, there are installation videos on the Ecobee web site that walk you through step by step.  After powering up your HVAC system, the Ecobee 3 does a quick check of the wiring to determine the wiring configuration.  If everything checks out, you move on to equipment configuration.  This is answering simple questions about what you have installed (heating, cooling, dehumidifier, etc.).  After that, select basic preferences such as Fahrenheit or Celsius, cooling set point, heating set point, the name of your thermostat, and so on.  This isn't really a super critical step, and most things can be changed afterward, but the thermostat needs some setup as a starting point.  

Next is the WiFi setup.  Like any network connected device, it asks you to select the SSID, and password for your wireless router or cable modem.  For most, a quick login connection will suffice.  For those that are more security conscious or having a non-typical wireless setup, there are fully configurable options for the wireless connection.  You can choose a static IP address, security protocol (WEP/WAP/WAP2), network speed, and so on.  Once connected to WiFi and given a valid IP address, the thermostat 'phones home' to the Ecobee mothership for validation, updates, and logging.  At this point you choose login credentials for the Ecobee site, and your thermostat is registered.  Should you have difficulties connecting to Ecobee, there is surprisingly complete set of tools built into the firmware to assist you in troubleshooting, including a ping utility to the gateway, a ping utility to the Ecobee mothership, a ping utility that allows you to ping any address, a signal strength indicator,, and a logger to see what activity has taken place along with the results.

Setup of the wireless remote sensors is also just about foolproof.  The toughest part of the remote sensors to me was, determining where they would do me the most good.  Of course, there are the built in sensors in the Ecobee3 thermostat itself.  It detects temperature, humidity, and occupancy/proximity.  When one approaches the thermostat, and stays in front of it for more than just a second or two, it moves off the default screen, and three icons appear at the bottom for 'Menu', 'Live Weather', and 'Quick Settings'.  Otherwise, it simply detects your activity in the room, which is used in conjunction with the settings to determine whether you are home, and how you want your house to set the temperature (more on this later).  The external sensors are very small, and detect both temperature and occupancy.  They can be wall mounted or attached to the included stand.

The Ecobee3 comes with one external sensor.  Over the few months that I've tested the Ecobee3, I've purchased several more.  They are sold in packs of two.  For now, let's just start with the one.  Pairing it with the thermostat is pretty easy; just remove the plastic tab that keeps that isolates the battery, and the thermostat senses that the sensor is now active.  Follow the prompts to name the sensor, ideally with it's location in your home.  Place the sensor in a location where you spend a lot of your time, and it will report back to the thermostat whatever the temperature is in that area.  The Ecobee3 will average the temperature from the sensor on the thermostat itself, with that of your newly placed remote sensor.  My findings are that you can place it a good 45 feet away, perhaps even longer if there isn't not much interference.  I found that concrete block walls and window glass seemed to degrade the signal more than anything else.  Framed wooden walls with sheet-rock seemed relatively transparent to the signal.  I kept mine on the stand as I experimented with placement.  One tip for placement is that you will probably want the sensor facing the room it is installed in.  This is because the occupancy sensor is on the front.  If detection of the rooms occupancy is not important to you, it can be place behind other objects to keep it out of site.  If you do obstruct the occupancy sensor, you will not be able to use some the of the thermostats more advanced features such as 'Follow Me' and 'Smart Home/Away'.

 

Features

Like other smart thermostats, and most of the programmable ones, there are some basic default settings for daily temperature control that are ready to go the first time you power it up.  One thing that differentiates smart thermostats from those that are simply programmable is the ability to detect if you are home or not.  By determining occupancy, smart thermostats have not only the time element, such as night-time, during the workday, or weekends, but also complex scheduling based on actual living conditions.  The Ecobee3 accomplishes this by the use of in-house sensors.  As noted above, one sensor is built into the thermostat itself.  There is also one in each remote sensor.  Even if there is a time band, say from 7:30a to 5:30p on Monday through Friday (while you are away at work) that is normally an 'Away' status, the Ecobee3  changes over to the 'Home' status once the sensors report activity in the house.  Of course, as a smart thermostat, nearly every feature can be set, adjusted, monitored, or simply viewed from anywhere using your mobile device.  I tested mine using an android based mobile phone, but there is an app for Apple devices as well.

Smart Home/Away:  For a really simple program, really all you have to do is create temperature settings for 'Home', 'Sleep', and 'Away'.  Once you've done that, create a schedule for when the 'Home' and 'Sleep' times should be in effect.  Lastly, set the 'Smart Home/Away' setting to 'Enabled', and you are done!  Now the behavior of the Ecobee 3 will be to follow your time schedule, unless you or your families behavior conflicts with the base time program.  Suppose that you are normally away during the typical workday, but you come home early one day, say, right after lunch.  The house should be set to it's 'Away' temperature setting at this time, which might be several degrees cooler than the 'Home' setting for wintertime.  This is saving money by not heating your home while you are not in it.  Normally, it wouldn't heat up again until just before you were due to get home, but, you came early this day.  As soon as the Ecobee3 or one of its remote sensors picks up your presence, the 'Home' setting overrides the schedule, and the heat is turned on.  Some other thermostats have another way of determining your home/away status.  They use a technique called geo-fencing.  This is where the thermostat keeps in contact with your GPS enabled phone to determine where you are.  As you approach your home, the app on your smartphone signals the thermostat that you ar nearby, and takes the appropriate action.  Since the trigger is entirely dependent upon the GPS location of the holder of the smart phone, each inhabitant of the home would have to have their GPS enabled smartphone on, with them, and registered with the thermostat.  The Ecobee3 does not have this feature built in, however, it can be accomplished easily with IFTTT, utilizing a pretty much off-the-shelf recipe, if that is a function that is important to you.  Another scenario that the Ecobee3 takes advantage of to save you money works just the opposite of the previously described function.  Let's suppose it is your normal at home, non-nighttime, non-workday schedule, perhaps a Saturday morning.  However instead of staying home, you go out on a day trip somewhere.  The 'Away' function kicks in, due to lack of activity on your occupancy sensors, and your house temperature is set to your 'Away' schedule.  This will allow for a wider range before your heating or cooling equipment starts running, saving you money.  It is also a benefit if you have a room that is rarely occupied, such as a guest room.  Why allow a little used space to be part of the calculation for the comfort setting of your entire home?  Should you have a guest, the room now becomes averaged in with the rest.

Follow Me:  This feature is unique to the Ecobee3.  Since there you can potentially monitor the temperature in any room in your house, and any place you can do that you also know the occupancy of that space, you can allow the thermostat to set the comfort level only for the space that is occupied.  This is really useful if you work at home, and are only occupying a single room for hours at a time.  If you are the only person in the home, it can set the comfort level to just where you are in your home.  In my case, I have an upstairs office, which always got too warm in the summertime, but I don't regularly spend a lot of time there.  The combination of 'Follow Me' and 'Smart Home/Away' provides a great solution.  It makes the room comfortable only when I am in it, and the rest of the time I'm saving money because I'm not heating or cooling it when I'm not there.  The guest bedroom in my home is always a little off from the rest of the house also.  Trying to keep it comfortable when we have a guest was easily forgotten.  Not so with the Ecobee3.

Vacation mode:  Setting the Ecobee 3 to 'Vacation' mode is fairly simple.  Either set it manually as you are leaving, or, set up a schedule that kicks in automatically.  This is a feature that many programmable, and most smart thermostats have.  Probably the very best part of this feature is being able to set it remotely from anywhere.  Unlike your your other stuff (iron, oven, garage light, etc.), you just pull up your Ecobee app, and toggle the 'Vacation' mode.  Done.

Reminders & Alerts:  These notifications are a powerful set of features that you may not know you needed or wanted.  Not having to keep a calendar or maintenance log is pretty handy.  For example, if you have a maintenance schedule that includes having an checkup on your HVAC system whether it needs it or not, simply enter the schedule interval, and at the appropriate time, it will remind you of your next service date.

 This feature is really great if you have a maintenance contract on your system, and your service contractor is not timely with their visits.  Additional reminders and alerts are:

• Furnace Filter:  You can set this to hours or months.  With the 'Hours' setting, you can base it on actual hours of run-time of your equipment.  Setting this to 'Months' instead, has your reminder pop up after however many months you set, regardless of run-time.
•  UV Lamp:  If you have a UV Lamp in your system, it will alert you to when to change the bulb based on time.
• Low Temperature:  Pretty self explanatory; this reminder can come in handy if you live in a region where freezing water pipes may be a concern.
• High Temperature:  If you live in a region where there are routinely high temperatures, this is usually your first indication that your equipment may not be working.
• Low Humidity:  In low temperature climates where the heat is on most of the time, low humidity can be an issue.  This alert may let you know if your humidifier is not working.
• High Humidity:  High humidity can be an issue in homes in hot humid climates.  A high humidity alert may be your first indication of malfunctioning equipment.

Basic Settings:  Most thermostats don't require a lot in the way of identifying your homes characteristics.  The Ecobee3 does, and for good reason.  The more it knows about your home, the smarter it can be about tailoring your comfort and savings.  I'll skip all the settings that nearly all programmable and smart thermostats share, like time of day, time zone, and so on.  One set of settings that stands out is location.  By entering you actual address, it sets up a lot of features that you really wonder how you did without.  First, the weather; it sets up all the weather features such as the local weather conditions on the home screen, as well as the forecast for the remainder of the day, and the next four days.  It also uses this information for comparing your homes efficiency to others in your area (more on the later).  It also uses the outdoor temperature to produce charts for you to assess your systems performance.  On the web (non-mobile) interface to your Ecobee3, it even shows an aerial view of your home.  This really doesn't do much for you functionality-wise, perhaps unless the view alerts you that you entered your address wrong.  It does have a cool factor though.

You can also name your thermostat here.  This is something you can change any time, but the name should be chosen carefully.  I was interested in using voice control of my thermostat using Amazon's Echo, and during the setup of that device, you have to call the thermostat by name.  For example, if you name your thermostat simply 'Home', you would have to say, "Alexa, set [Home] to 75 degrees".  If you were to simply say, "Alexa, set temperature to 75 degrees", she would then ask you which device.  It works, but it is another step.  I chose a name I thought would be humorous, based on my love for science fiction movies and television shows, but that name soon became cumbersome and confusing to my family members.

Enabling Smart Recovery Heat & Cool modes will allow Ecobee3 to figure out how long it takes to get your home up to or down to the desired temperature once the setting changes.  This allows the Ecobee3 to start the heat or cool cycles with enough time to hit the desired temperature right at the scheduled time on your schedule.  If you want to wake up or come home right at your desired temperature, this feature is for you.  In addition to these more basic settings are many others that fine tune your Ecobee3 to very granular detail.  These are great for those tinkerers among us.  Just a few examples:  Minimum compressor run time, temperature delta triggers, minimum fan run-time per hour, fresh air cooling, heat/cool run down (utilizing the last of heat or cool in the coils before shutting off the compressor) and many other smart features.  Most are defaults or set and forget type features that make up the complex 'smart' algorithms that make your system run more efficiently. 

Access control allows you to set who has access to your Ecobee3.  This could be very helpful if you have a vacation rental property.

Another group of settings unique to the Ecobee3 is titled 'Property Characteristics'.  Here you answer questions on building style (detached, condo, apartment, etc.), building size in square feet, number of floors, number of bedrooms, number of full-time occupants, and age of the building.  These settings help Ecobee with generating HomeIQ reports.  You can even add your contractor information in the settings.  Don't have one?  Choose from a list of Ecobee preferred contractors in your area right from your settings..

HomeIQ:  This is where you find out how you are doing with your Ecobee3.  After a few months of activity, I can now tell how well I am doing.  Using the web interface, logging into your account gives you a set of reports and graphs that really give you some insight into cost savings, performance, and run details of your system.  To start off, there is a summary page that just gives the top level stats, all of which can be drilled into.

From there, you can get into two basic sub-categories that break down operating statistics, and your homes efficiency (including comparisons to other similar homes).  First, let's see if the Ecobee3 is paying for itself.  This next graph shows a comparison to a regular 'dumb' thermostat that has a basic 'hold' setting.  This may not be the fairest comparison, because one might be in the habit of turning the thermostat up or down as leaving or arriving to the home.  Alternatively, there might have been a programmable thermostat in place that lowered or raised the temperature depending on the time of day and day of week.  In my case, there was a 'dumb', non-programmable thermostat that we kind of remembered to adjust depending on our comings and goings, so this graph is probably as close to accurate as one could get for my specific circumstances.

This report reports on any month of your choosing, with the default being the last month it had a full set of data for.  It estimates your savings for that month, as well as the amount of savings since registering the device.  As can clearly be seen in the graph, I have already more than paid for the Ecobee3, it's external sensors, and then some.  This is just slightly less than nine months of data, which makes it look even better given my goal of saving money by this purchase.  Another thing to consider in ones overall benefits is the reduced hours of run-time of your HVAC system.  In my case, I saved 51 hours of run-time during this period.  That is 51 hours less wear and tear on my system.

To take a look at system run-time, I've chosen a few different slices of time to depict how the Ecobee3 controls the system at different times.  This first one shows several events happening, and two almost at once,  As the mode changes from 'Sleep' to 'Home' at 6:30a, the desired temperature band changes, and in the top part of the chart the fan and the heater run briefly to bring the house up to temperature.  Shortly after, the Ecobee3 determines there is no one at home, so it widens the temperature band.  Around 5:00p, the two events happen; the outside temperature begins to drop, and the house becomes occupied.  At that time, the fan and heater starts warming the house up until about 9:30p, when the 'Sleep' program is in effect.

Next, the chart that follows starts with 'Sleep' mode in effect until the house is started warming just ahead of the 6:30a 'Home' mode.  Again, the house stays heated until it detects the occupants are away, then settling on a wider temperature band.  The outside temperature rises until occupied, but by that time, there is no longer any need for heat, so the equipment stays off.  This is a good depiction of a time the equipment would have run for longer during the day, had there been a traditional thermostat in place.  Note that where the cross-hairs highlight the equipment run-time at the top of the graph, the fan ran slightly longer than the heater.  It was taking advantage of the residual heat in the coils before shutting off the fan.

This next graph is a great example of the remote temperature sensors at work.  The top band depicts 'Sleep' mode transitioning to 'Home', with a brief bit of away (in the purple), followed by 'Sleep'.  As the day progressed you can see the occupancy sensors showing when those areas are occupied.  Also, at the point in time where the cross-hair is centered (12:00p), you can see what the remote sensor temperature readings were.

Lastly, the next shart shows what impact the weather had on the system.  This gives you a pretty good feel for how much equipment run-time there has been for the given temperatures during the month.

 

 

Pros & Cons

When weighing the pros and cons of the Ecobee3, I first tried to look at it in the context of my original goals.  I had four criteria I was interested in, and selected the Ecobee3 as the thermostat most likely to meet them.  I researched and compared everything I could get my hands on, but nothing is like the actual experience of purchasing, installing, tinkering with and measuring the results yourself.  Most people, myself included, aren't going to spring for two $200+ thermostats to do a side by side comparison, so you pretty much have to make your best pick and dive in.  That said, let's look at the original four criteria:

• Energy Savings:  Pros - I can without question say that it has resulted in energy savings, more than enough to pay for itself in less than a year.  I live in Florida, where the climate requires greater use of air conditioning than heat.  During the hottest months of the year, it was not uncommon to have a $400 or higher electric bill, most of which went to cooling.  This year, I never broke $300 during those same months.  I've yet to test the heating during the coolest months here, but expect to see some savings there too.  Had I paid a licensed contractor to install it for me, I likely would have paid $100 or so for the install on top of the cost of the Ecobee3.  In the nine months I've had it installed, that would have been about the break even point.  Cons - Despite my savings, I'm the kind of guy that likes to see the detail; what exactly did it save me?  I would like to see a feature where I can input the cost per kilowatt hour (kwh) so that I can translate the reduction of one hour of equipment running to a real dollar cost.  Of course, I would also have to know what kind of power my equipment consumes per hour for this to be accurate, but it could probably be summed up into bands by the HVAC system capacity and the age of the unit.  One thing to consider is the age of my system - it is an older one, no longer manufactured, and it is a much lower SEER rating than ones manufactured recently.  Therefore, since I have a less efficient system (nearly 20 years old now), the newer more efficient systems are going to yield less savings than mine would.  As a rough estimate, my nine month payoff, might be an 18 month payoff if the newer system was twice as efficient as mine.
• Flexibility:  Pros - High marks for flexibility.  I had multiple installation and wiring options, and even purposefully choosing the more difficult one, it was still a snap.  Cons - none that I can see.  If I do purchase a new HVAC system any time soon, I will make sure it does not exclude the use of the Ecobee3.  No other thermostat I've seen has a whole house view like this one does.
• Ease of Use:  Pros - Everyone in the family can use it, whether it is from the Ecobee3 itself, or the integration with other systems.  Cons - None at this time.
• Smart Home Compatibility:  Pros - Setup on the Amazon Echo was simple.  Integration with Wink was easy as well, but I found that we rarely use it to control temperature.  One huge plus that I hadn't counted on came with the Wink integration.  Wink can display the sensor information, and use it, for home automation.  Cons - I've had to refresh my Wink setup on this device, but believe it to be more of a Wink issue than Ecobee.  With the Echo, the setup must be done on every account on the Echo.  It is cumbersome, and really more of an Echo issue than Ecobee.

Altogether, the major goals were met or exceeded.  I've learned a few other things along the way, and will add them here as additional Pros & Cons:

• Stand alone operation - For a week or so, I was having problems with my internet service provider.  They were intermittently blocking ports, their router required a lot of rebooting and configuration.  During that time, the Ecobee3 could not 'phone home'.  At first, I thought it was the thermostat configuration, and the way it appeared using their built in diagnostics, was that my connection was good out to my router, but could not get to Ecobee's servers.  I called Ecobee's technical support to verify my findings before calling my ISP.  Ecobee's technical staff were great; walking me through the steps and validating my findings.  Their goals was to determine if the thermostat itself was at fault, which would mean a swap out.  Once that had been eliminated, they walked me through a few more troubleshooting steps, and ended up verifying my original conclusion, the ISP.  Even though the fault was not theirs, as far as we could tell, they kept the ticket open while I attempted to resolve the issue with my ISP.  The ISP denied they were blocking the ports that Ecobee uses, but somehow the issue cleared itself up the next day, with no action from myself.  The Ecobee3 reconnected to it's servers, and reported to me that connectivity was restored.    Pros - Even though connectivity was lost, the Ecobee3 continued to work; it was missing the weather information, and I couldn't control it from afar, but, the Ecobee3 continued to operate just like a programmable thermostat, only with more smarts.  Great customer service and technical staff when calling Ecobee.  No long wait on the phone, and the first person I spoke to was knowledgeable and met me at my technical level, rather than pointlessly walking through a long script.  I was not transferred once.  Cons - This incident did expose the fact that the Ecobee3 does require constant communication with the Ecobee servers.  While this was going on, I could not use the phone app to look at or adjust my thermostat settings, even while on the same subnet..  This also caused a gap in my statistics and charts.
• Settings - The ability to get under the hood is one thing area that sets this thermostat apart from others in it's class.  Pros - Nearly everything is configurable and individually addressable.  I've not found one setting that I couldn't turn on or off, or just tweak a little.  If you don't care about the detailed settings, the default learning and setting it does is just phenomenal.  
• Remote sensors - These are the stars of this thermostats feature set.  Pros - easy to set up and install.  Can be moved and renamed according to your needs.  Cons - In Wink compatibility, it would be nice if I could trigger off of the occupancy of the sensor in addition to the temperature.  It is readable on Wink, just not accessible by Winks's Robots, which are triggers to make things happen.  Occasionally, the remote sensor will lose connectivity with the Ecobee3.  If it happens repeatedly, you have to move the sensor around the room room for better connectivity.  Other times, it just clears itself up.  I haven't figured out why it can go months without a blip, then two or three in a row.  It doesn't affect the other functions of the Ecobee3, but can be annoying.

 

 Conclusion

If you are in home with more than two rooms and you are interested in saving money/energy, I don't know why you would look anywhere else.  The ability to measure all your rooms, and the ability to stand on it's own even with a loss of internet connectivity, lifts the Ecobee3 above it's competitors.  If you have comparable experiences with other thermostats, or findings different than mine, good or bad, please leave comments.