About Emerson Sensi
Sensi is a smart-thermostat brand built by Copeland, an HVACR manufacturer with more than a century of compressor and controls engineering behind it. Copeland traces back to 1921 as the Copeland Corporation, was acquired by Emerson in 1986, and became a standalone company again in 2023 after Blackstone completed its acquisition of a majority stake in what had been Emerson's Climate Technologies business, in a deal valuing the unit at $14 billion. The Sensi thermostat line launched under the Emerson name and continues today under Copeland, headquartered in St. Louis.
The Sensi range spans the battery-powered ST55 for homes without a C-wire, the touchscreen ST75 (Sensi Touch), and the newer Sensi Touch 2, which adds support for remote Sensi Room Sensors. Copeland has been named an ENERGY STAR Partner of the Year for its Sensi thermostats for five consecutive years, and documents an average 23 percent HVAC energy savings figure for households using Sensi's scheduling and geofencing features. In our own testing on DIYRated, the ST55 stood out for genuinely requiring no C-wire and no extra adapter hardware, backed by a 3-year warranty routed through the same support organization that backs Copeland's compressors and White-Rodgers controls.
Brand website: sensi.copeland.com
What Emerson Sensi makes
Emerson Sensi's range runs wider than the products we review. The lines we know best from our own testing are marked with a star:
Sensi Lite (ST25)
entry-level Wi-Fi programmable thermostat, no C-wire required
Sensi Smart Thermostat (ST55)
battery-powered smart thermostat, no C-wire required — featured on DIYRated — featured on DIYRated
Sensi Touch (ST75)
touchscreen color display smart thermostat
Sensi Touch 2
touchscreen smart thermostat compatible with Sensi Room Sensors
Sensi Room Sensors
remote temperature sensing accessory for Sensi Touch 2
Why we recognized Emerson Sensi
The DIYRated Top Brand recognition isn't paid for and can't be applied for. We award it to the brands whose products consistently stand out in our hands-on category reviews. Emerson Sensi earned it on the strength of the products below, evaluated the same way every product on this site is: bought, put to work on real jobs, and judged on merit.
Emerson Sensi products we rated highly
Sensi Smart Thermostat ST55 (Emerson)
Runs on two AA batteries with no C-wire required, no power-extender kit, and no rewiring at the air handler, making it one of the easiest installs we tested in the category. It carries more than 22,000 verified Amazon reviews at 4.4 stars, the largest review base of any smart thermostat in our testing, plus ENERGY STAR certification with a documented 23 percent average HVAC energy savings claim. Copeland backs it with a 3-year manufacturer warranty handled by the same HVAC support organization behind Copeland compressors and White-Rodgers controls.
Read the 8 Best Smart Thermostats of 2026: A Contractor's Honest Picks guide →What earned Emerson Sensi the recognition
- Backed by Copeland, the HVACR manufacturer formerly known as Emerson's Climate Technologies division, with a lineage running back to the Copeland Corporation's founding in 1921.
- Named an ENERGY STAR Partner of the Year for its Sensi smart thermostats for five consecutive years, with a documented average 23 percent HVAC energy savings claim.
- The Sensi ST55 runs on two AA batteries with no C-wire required in our testing, one of the most accessible installs of any smart thermostat we've reviewed.
- More than 22,000 verified Amazon reviews at a 4.4-star average on the ST55, among the deepest review bases of any smart thermostat we've covered.
- A 3-year manufacturer warranty routed through the same support organization that backs Copeland's compressors and White-Rodgers controls.