Are you wanting to get on the smart thermostat bandwagon, but aren’t sure if it’s worth the $249 price tag of the full-featured models like the ecobee3 and Nest? Then has ecobee got a deal for you. They recently added the ecobee3 Lite to their line-up with a very tempting MSRP of $169. If you’re wondering what features you have to give up for that $80 savings, ecobee answers that question in their FAQ:

The ecobee3 lite is very similar to the ecobee3, but does not include support for Wireless Room Sensors, Occupancy Detection, Smart Home/Away features, and Accessories (HRVs, Ventilators, Humidifiers, Dehumidifiers). But you still get all the other smart functions offered by the ecobee3; Smart Recovery, Schedule and Vacation settings, Home IQ, connection to Homekit/Amazon Echo/IFTTT and SmartThings, Alerts and Reminders and our Web Portal and Mobile App.

The majority of smart thermostat users probably won’t need to hook up an an accessory like a humidifier to their system, so the loss of that feature doesn’t feel like that big a deal. The wireless room sensors, however, are what really set the flagship ecobee3 apart from the competition, so that’s where the $80 in savings should really be measured for the average homeowner. If the additional features that come by virtue of the built-in and remote occupancy sensors (Smart Home/Away, Follow Me, and occupancy detection) aren’t worth $80 to you, then the ecobee3 lite is the ideal way for the budget conscious buyer to make their home a little smarter while making their energy bill a whole lot smaller.

I was an early adopter of the original ecobee Smart Thermostat since its launch, and then I upgraded to multiple ecobee3 units at our main home in Seattle, Washington in September 2014. In November 2014, I documented how to upgrade from an original ecobee Smart to an ecobee3 at our place in Utah. The only place I was still using an original ecobee Smart was at our Cabin near Wenatchee, Washington. I was primarily using it for its remote management capabilities, so we could turn on the heat or AC before the 2.5 hour drive and the place would be (mostly) heated or cooled by the time we walked in the door. I didn’t see much of a need to upgrade the original ecobee because the electricity in Wenatchee is the cheapest in the country at 2.5 cents per Kwh, compared to 10 cents per Kwh in Seattle. But when the ecobee3 Lite came out, I decided it was the perfect opportunity to try it out. I have to shamefully admit that when I replaced the old-school Honeywell thermostat that used to be at the cabin, it left a large mismatched paint spot on the wall. I always swore I’d fix it… but never got around to it. So here’s what I was starting with at the cabin, prior to upgrading to the ecobee3 Lite:

Original ecobee Smart Thermostat at the Cabin

Yes, I know, hideous.

What’s in the Box?

I’d previously made an ecobee3 unboxing video, and the unboxing of the ecobee3 Lite was pretty similar, though it’s clear ecobee has made an effort to make things even more sleek and modern. At first glance, the ecobee3 Lite looks a like like its older brother:

ecobee 3 Lite unboxing

There was nothing wrong with the ecobee3 manual, but the ecobee3 Lite manual received a total redesign and is very easy to follow:

ecobee3 Lite manual

Underneath the manual was the mounting plate / wiring harness, mounting hardware, and the updated Power Extender Kit (PEK), which allows you to install the ecobee3 Lite even if you only have 4 thermostat wires available at the thermostat location on your wall.

ecobee3 Lite mounting plate, hardware, and PEK

The new PEK works just like the original PEK, in that it lets you connect to the most common 5 terminals on your furnace’s control board: Yellow (AC), White (Heat), Green (Fan), Common (Ground), and Red (Power).

Five wires coming out of the ecobee3 Lite PEK

The big improvements in the PEK are the push-button quick connectors for the wire coming from the wall location:

ecobee3 Lite PEK push-button connectors

…and a magnetic pad on the rear of the new PEK, which makes it easy to mount to nearby metal surfaces such as a furnace panel or sheet metal ducting:

Rear of the ecobee3 lite PEK has a magnetic mounting pad

Fortunately, I had plenty of wires available at the cabin, so I didn’t need to use the PEK. I just thought there were enough improvements in the new PEK that I still felt it worthwhile to share them.

The ecobee3 Lite’s mounting plate looks very much that of the ecobee3, just a bit smaller and with fewer connectors, but still comes with the bubble level to make OCD wall-mounters happy:

ecobee3 Lite wall mount

The box also contains a larger plate to cover up any holes or paint mismatch from previous installs:

Larger plate for covering up old thermostat locations

Out with the Old, In with the New

Because I was upgrading from an original ecobee Smart, I went through all of my settings screens and took photos. This makes configuring the replacement a lot easier. Taking a photo of the old thermostat’s wiring diagram is always helpful:

ecobee Smart’s wiring diagram

But even if you’re starting from scratch and not replacing an older ecobee with an ecobee3 Lite, the easy-to-follow instructions in the manual will get you up and running quickly.

After snapping photos of my settings, I shut off the power to the furnace (very important) then disconnected my old thermostat (ignore the additional wires to the left, which are from a Honeywell air filter).

Removing the old thermostat

Then I went downstairs where the old ecobee’s equipment interface was located, disconnected it, and connected the wires from the upstairs thermostat location directly to my furnace’s wiring terminal. If you’re replacing a traditional thermostat, you won’t need to do that step. The newer ecobee3 and ecobee3 Lite no longer require an equipment interface, so most homeowners will only have to re-wire things at the thermostat wall location (but read the manual for your particular setup).

My old thermostat was not centered on the wall, and it didn’t have enough slack for me to center my ecobee3 lite, so I decided to wire-nut a couple feet of thermostat wire to the existing wires so I had more flexibility in my install. I also decided to cover up that ghastly unpainted spot once and for all, so I hit the local Hobby Lobby and spent $20 on a rustic wood panel wall-hanging. It was a bit too wide, so I used a saw to chop down the sides to the width I needed, wiped some wood stain on cut ends with some stain, drilled a hole in the middle for my extended thermostat wire, mounted the ecobee3 lite mounting plate directly to the wood, then screwed the wood panel into a wall stud (thank goodness it was centered):

ecobee3 wall plate mounted to wood panel

With plenty of slack, I was able to easily connect the appropriately-colored wires to the ecobee3 Lite mounting plate, then tuck the slack behind the wood panel:

ecobee3 Lite mounting plate installed

Finally, I gently pressed the ecobee3 Lite into the mounting bracket and turned on my furnace. After a few seconds, the unit sprang to life!

Getting Set Up

Registering the ecobee3 Lite was easy with an iPhone. When I opened my iPhone’s WiFi screen, the ecobee3 Lite as there waiting to be set up:

iPhone setup of ecobee3 Lite

It was as simple as typing in a code that appeared on the ecobee3 Lite’s screen to sync it with my ecobee account so I could manage it remotely:

Connecting the ecobee3 Lite to an ecobee account

Once everything was set up, my ecobee3 Lite was happy, and went into its automatic temperature calibration mode:

ecobee3 Lite calibration mode

While it calibrated, I used my app to check the differences between the ecobee3 and ecobee3 Lite’s app menu options. As expected, they looked very similar. The ecobee3 at my Seattle house menu looks like this:

ecobee3 mobile app main menu

And the ecobee3 Lite looks the same, without the Sensors menu item:

ecobee3 Lite mobile app main menu

Finishing Touches

After setting up my heating and cooling preferences (some via the ecobee3 Lite’s screen and some via the app), I decided to dress up the install a bit. I took the antlers that had been on the wall above the old thermostat and mounted them to the wood panel:

Antlers added to punch up the rustic vibe

When everything was done, the finished product looked like the perfect mix of modern and rustic:

Install complete!

Making Your Smart Home Smarter

If you’re into more extensive home automation, I run a SmartThings hub at the cabin, as well as an Amazon Echo Dot, both of which integrate wonderfully with the ecobee3 and ecobee3 Lite. I can control the ecobee3 Lite using the ecobee app, or I can trigger thermostat events based on any SmartThings sensor or input (like automatically lowering the temperature when my SmartThings hub senses my phone has left the cabin for the afternoon), or I can say “Alexa, turn the Cabin thermostat up 2 degrees.” With an MSRP of $169, the ecobee3 Lite is an unbeatable choice for those looking to connect a smart thermostat to a more widely integrated smart home.

Final Thoughts

So is the ecobee3 Lite right for you? If the price of the flagship ecobee3 is out of your budget, then the less expensive ecobee3 Lite is a great way to get the basic features of the more expensive model without breaking the bank. If you’ve got a home that wouldn’t benefit from remote sensors, the ecobee3 Lite is a better choice than anything else on the market. It’s just as easy to install, set up, and use as its slightly older brother. And it looks just as good on your wall, too… just make sure it’s centered. 🙂

If you’re looking for a more in-depth review of the ecobee3 Lite, check out my original ecobee3 review, my ecobee3 two month follow-up, and my HomeKit-enabled ecobee3 review. The ecobee3 Lite shares the majority of the ecobee3’s features, is HomeKit-enabled, and uses the exact same app and web interface as the ecobee3. The only difference is the absence of remote sensors and occupancy detection (meaning Smart Home/Away and Follow Me features aren’t available), and the ability to add accessories like a humidifier. Apart from that, the ecobee3 Lite looks and acts exactly like a HomeKit-enabled ecobee3.

I welcome your questions, comments, and feedback below! But if you’ve got an ecobee3 or ecobee3 Lite technical question, you’re better off contacting ecobee support or joining the conversation at SmartHomeHub.