Ecobee 3 vs CT100, which solution is best

I’d like to get some feedback on which solution would be better for the goals I’m listing below. I’ve narrowed the running down to the Ecobee 3 and the CT100.

Info on the house:
About 4,000 sqft, dual story, separate HVAC for 1st and 2nd floors.

Integration desires:
We obviously have ST, also have several Amazon Echo/Dot around the house. I’d like a thermostat that can tie in with both the Echo at home as well as some sort of HA within the house (i.e., allowing control based on room sensors/present sensors) and a system I could control away from home as needed.

Cost. With dual two HVAC units and thus 2 thermostats the Ecobee solution would cost $400+ whereas the CT100 would be around $170+, not the deciding factor but something I have to consider and so is the Ecobee for my needs worth 2x compared to the CT100.

(I moved this over to projects just to make sure you get an answer specific to your own particular situation.)

I think this is one of those cases where different things work for different people.

The biggest advantage to the ecobee is the ability to set up zone Controls based on multiple sensors in multiple rooms. So you could average the temperature in three upstairs bedrooms and use that to control the thermostat at night, while letting the rooms where people are active define the important temperature settings in the early evening. Note that this is very different from just a “upstairs” and “downstairs” distinction as you are both averaging the temperature sensors from multiple rooms and taking into account where motion is present.

It’s technically possible to do this by adding a lot of additional sensors to a CT 100, but this is the use case that the ecobee was designed for, and its own sensors are just likely to be both more efficient and more effective for this use.

@yvesracine could probably say more, he is the author of a number of smart apps for use with ecobee and his products are very popular in the community.

Of course, there are probably just as many people who just have very simple thermostat requirements, and choose the CT 100 for budget reasons. So it really depends on what you need done. :sunglasses:

Thanks, I deliberately left out that I’ve already read so many of the posts here on the various brands as well as taken a detailed look at @yvesracine work and @RBoy stuff too. I was hoping for responses like yours that push the multi room zone as the benefits to either system. And it does appear to be easier with Ecobee than CT100. I also wanted to know reliability issues. For example, CT100 is completely within ST ecosystem whereas Ecobee I believe is technically outside and merely tied in, probably describing this wrong, but my meaning is that Ecobee is sort of outside my HA solution.

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Hi @smgran,

I’ve done a summary of the pros & cons of ecobee3 vs. other zigbee or zwave thermostats.

It all depends on your requirements and budget (or course).



This is perfect. I keep forgetting about the wiki for info.


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My 2 cents, wouldn’t not being Z-Wave / Zigbee be a con to the native ST environment?

Well, I can add it as a con, but there are a lot of wifi Things supported by ST…

Since Smartthings does very little locally, and no thermostats, it shouldn’t really make any difference. There are many devices officially supported in SmartThings that do not use Zigbee or zwave, including Harmony, the Philips Hue Bridge (The bridge talks to its bulbs via its own zigbee network, but the ST/bridge integration is LAN), wemo, Sonos, Echo, Sami, etc.

I added it as a con for Ecobee and a pro for the Zigbee / Zwave thermostats… Just to be thorough.


Very true, a Z-Wave will be native to ST hub as in no additional hardware needed (WiFi router etc) hence I prefer Z-Wave to WiFi devices. Also allows for Z-Wave device to run longer on batteries.

There is so much to think about, but I wanted to thank all you guys (“the heavyweights” as I like to think of you all) :slight_smile: for the info. One of the benefits to me with ST is the flexibility it provides for HA solutions allowing the customer (me) to decide what works best for each particular scenario.

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