Multi-Zone Thermostats
Choose smart thermostat replacements for each existing low-voltage HVAC zone, and avoid confusing room sensors or fans with true zone control.
Emerson ST55 Smart Thermostat, Wi-Fi, Programmable, Works With Alexa, Energy Star Certified
✨ Upgrade your home with the Emerson Sensi ST55 Smart Thermostat ✨
Ever wished your thermostat was as smart as your phone? Well, now it can be. The Emerson Sensi ST55 is a breeze to install yourself—no common wire needed, and it plays nice with most HVAC systems. Plus, it’s not just smart; it’s thrifty, too. Think 23% energy savings thanks to flexible scheduling and a mobile app that’s so good, it’s practically showing off.
And here’s something you don’t hear every day: Privacy Protection. That’s right, Sensi keeps your data to itself, no selling to third parties. Because your thermostat shouldn’t be gossiping about your heating habits.
It’s also got your back with Smart Maintenance. Imagine getting a nudge when it’s time to change your filter or if your HVAC starts acting up. Handy, right?
Compatibility? Check. Whether you’re team Alexa or Google Assistant, this thermostat fits right in. Voice control isn’t just cool—it’s downright lazy (in the best way).
And because we’re all trying to save the planet (and our wallets), it’s Energy Star Certified. Lower bills and a smaller carbon footprint? That’s what we call a win-win.
General specs
- Brand: Emerson
- Model: ST55
- Seller: Retailer
- ID: B01NB1OB0I
- Shape: Rectangular
- style: DIY
- Voltage: 24 Volts (AC)
- Material: Plastic
- Backlight: Yes
- Item Weight: 13.6 ounces
- Screen Size: 5 Inches
- Control Type: Button Control
- Display Type: LED
- Power Source: Corded Electric
- Mounting Type: Wall Mount
- Control Method: Voice
- Controller Type: Vera, Google Assistant, Amazon Alexa, SmartThings
- Special Features: Filter Indicator, Clock Display, Fan Control, Auto Changeover, Daylight Savings Time Ready
- Product Dimensions: 1"D x 5.88"W x 3.75"H
- Included Components: Thermostat, free mobile app, 2 AA batteries, mounting hardware, wire stickers, installation guide, welcome guide with Sensi code, warranty booklet
- Number of Batteries: 1 AAA batteries required. (included)
- Warranty Description: 3 years.
- Connectivity Protocol: Wi-Fi
- Connectivity Technology: Wi-Fi
- Temperature Control Type: Programmable, Smart/Remote
- Specific Uses For Product: Boiler, Air Conditioner, Heat Pump, Furnace
- First listed by seller: March 30, 2025
If you are interested in more details, you can find full information on the seller's page.
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Emerson ST55 White
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| Brand | Emerson | Emerson | Sensi | Amazon | Emerson | Amazon |
| Model | ST55 | ST25 | ST25W | S6ED3R | ST75W | |
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| Price | €69.92 | €53.30 | €56.17 | €69.92 | €155.58 | €111.84 |
| Seller | Retailer | Retailer | Retailer | Retailer | Retailer | Retailer |
| Update | Jun 24, 2026 | Jun 24, 2026 | May 29, 2026 | Jun 24, 2026 | May 19, 2026 | Jun 19, 2026 |
| Connectivity | Wi-Fi | Wi-Fi | Wi-Fi | Wi-Fi | ||
| Control Methods | App | App, Voice | Touchscreen, App | App, Voice | ||
| Voice Assistant Compatibility | Alexa | Works with Alexa | Alexa | Alexa, Google Assistant | Alexa | |
| Smart Home Platform | Google Home | Google Home | Google Home | |||
Emerson ST55 White
€69.92
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