Nest Learning Thermostat vs. Honeywell Lyric T5
In this face-off, CR compares two smart thermostats from two titans
Thermostats were all ugly rectangular boxes until Honeywell introduced its circular T-86 model in 1953. These days you might be more likely to associate that iconic shape with the Nest Learning Thermostat (shown, above left), introduced in 2011.
The Nest, using automation and a smartphone app to address the consumer difficulty of programming a programmable thermostat, revolutionized the industry.
Now a host of smart thermostats make it easier to change settings and schedules via an app. They also connect to the internet for additional conveniences, such as remote control and voice control via digital assistants.
Not to be outdone by a Nest, which was then a scrappy startup (the company has since been acquired by Google), Honeywell released its own round smart thermostat called the Lyric Round in 2014, followed by a more affordable square-shaped model called the Lyric T5 (shown, above right), which is the best Honeywell model in our smart thermostat ratings.
The Nest Learning Thermostat and Honeywell Lyric T5 do very well in our tests, but they work differently.
How We Test Smart Thermostats
At Consumer Reports, we’ve tested hundreds of thermostat models over the years. And while once upon a time they weren’t very accurate, today’s models are able to keep rooms close to the set temperature.
So instead of testing for temperature accuracy, our labs focus on usability. That includes testing ease of manual operation (with the same standards we use for nonconnected programmable thermostats) and three criteria specific to smart thermostats: smart-home features, automation of heating and cooling, and wireless setup.
Our evaluation of smart-home features examines such elements as alerts, app control, and geofencing (which tells the thermostat when you’re coming and going). These individual features factor into a thermostat’s Smart IQ score, which allows you to see just how “smart” one thermostat is compared with another.
For automation, we check to see whether smart thermostats learn your habits and routines to adjust temperatures for you. And we test wireless setup, which includes connecting the thermostats to WiFi and setting up the corresponding smartphone apps. We also set up voice control with Amazon Alexa, Google Assistant, and Apple’s Siri if integrations with these digital assistants is available.
Findings from all these tests are folded into a model’s Overall Score—a straightforward, at-a-glance view of our comprehensive test results.
The CR Face-Off: Nest vs. Honeywell
Both the Nest Learning Thermostat and Honeywell Lyric T5 offer plenty of smart features, but the Nest offers just a few more that help it come out on top in this regard.
Each model lets you manage temperature settings and schedules from both the thermostat itself and a smartphone app. You can also make temperature adjustments with your voice using a digital assistant on your phone or a smart speaker. (For example, you could say, “Alexa, set the temperature to 74 degrees.”) Nest works with Amazon Alexa and Google Assistant; Honeywell supports the same, plus Apple Siri.
One of their crucial differences is automation. Both use geofencing (the ability to track when you come and go via the presence of your smartphone) to make temperature adjustments, but only the Nest can detect occupancy (through its own occupancy sensor) and learn your day-to-day temperature preferences through manual adjustments. The Honeywell instead requires you to do a bit of programming, such as setting temperature changes for when you wake up and go to sleep. The Honeywell has one advantage over the Nest: It allows you to create vacation schedules for when you’re away for multiple days.
Finally, the Nest gives you the option of adding remote temperature sensors (a longtime selling point of rival Ecobee). These are sensors you can place in other rooms away from the thermostat so that it does a better job at balancing heating and cooling. Honeywell doesn’t offer such sensors for its smart thermostats.
Both thermostats perform well overall in our tests, but for different reasons. The Nest does extremely well in our automation and Smart IQ tests because of its heavy focus on learning your temperature preferences and its vast array of smart features, but it doesn’t perform as well in our manual operation tests. The Honeywell does well in our Smart IQ tests, too, but not as well as the Nest. Where the Honeywell really shines is in our manual operation tests, owing to its easier-to-use controls. Both models perform roughly the same in our WiFi setup evaluation.
Most smart thermostats, including the Honeywell Lyric T5, require your thermostat wiring to have a common wire, or C-wire. (You can learn more about the C-wire in our thermostat buying guide.) The Nest Learning Thermostat doesn’t technically require a C-wire and will even work with older, two-wire HVAC systems. Some HVAC professionals caution against not using a C-wire, saying it can damage your HVAC system.
When it comes to which model is truly the best, the answer is the Nest Learning Thermostat. It offers more features and better performance through its automation. But which smart thermostat is best for you depends on the kind of thermostat user you are—hands-on or hands-off.
“If you love the way connected devices have automated many aspects of our daily lives, the Nest is for you,” Anzalone says. “But if you haven’t fully made that leap, the Lyric T5 provides similar connected functionality with more of a hands-on approach.”
That means much more granular control. If you’re someone who wants that control and isn’t into the idea of your thermostat “thinking” for you, the Lyric T5 might be your personal winner.
Despite their design differences, Nest and Honeywell both make great smart thermostats that should help you save money on your heating and cooling.
Even the smartest of thermostats won’t help if your family members constantly override each other’s temperature settings. If you want to help CR better understand AC wars, please take our You Test below.