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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: Amazon
- 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.
Amazon live offers
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Top live offer is the offer currently shown first for this Amazon listing. It may differ from the lowest available price.
FBA means the order is fulfilled by Amazon, even when the seller is a third-party merchant.
Shippable means the offer is listed as available for delivery on Amazon.
New, Used and Refurbished describe the item condition shown for that Amazon offer.
Top live offer
€68.87
Free shipping
New
Sold by Amazon
FBA
Shippable
New from
€68.87
Only from New + Shippable live offers
Used from
€53.47
Only from Used + Shippable live offers
New offers
Sold by Amazon
· FBA · Shippable
€68.87
Third-party seller
· Shippable
€86.09
Third-party seller
· FBA · Shippable
€89.07
Third-party seller
· FBA · Shippable
€89.10
Third-party seller
· FBA · Shippable
€89.13
Third-party seller
· Shippable
€90.39
Third-party seller
· Shippable
€125.17
Third-party seller
· Shippable
€126.41
Third-party seller
· Shippable
€127.63
Third-party seller
· Shippable
€128.94
Third-party seller
· FBA · Shippable
€129.14
Third-party seller
· Shippable
€131.98
Third-party seller
· Shippable
€134.33
Third-party seller
· Shippable
€135.16
Third-party seller
· Shippable
€147.36
Used offers
Used - Acceptable
· Third-party seller
· FBA · Shippable
€53.47
Used - Like New
· Third-party seller
· FBA · Shippable
€71.28
Used - Very Good
· Third-party seller
· FBA · Shippable
€74.52
Used - Like New
· Third-party seller
· FBA · Shippable
€76.07
Used - Very Good
· Third-party seller
· FBA · Shippable
€79.32
Used - Like New
· Third-party seller
· FBA · Shippable
€82.00
Offers updated: 9/1/26
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Price History for seller Amazon
Shipping options
Delivery to 
United States
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Available
Similar products comparison
| This item | Recommendations | |||||
|---|---|---|---|---|---|---|
Emerson ST55 White
|
Emerson ST25 Black Save about 23% on HVAC energy
|
Sensi ST25W White Easy DIY installation with built-in level
|
Amazon S6ED3R White Works with Alexa and Ring
|
Emerson ST75W White Works with Alexa, Google Assistant, Apple HomeKit
|
Smart Thermostat with C-Wire Adapter White On-the-go control via Alexa app
|
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| Brand | Emerson | Emerson | Sensi | Amazon | Emerson | Amazon |
| Model | ST55 | ST25 | ST25W | S6ED3R | ST75W | |
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| Price | €68.87 | €55.33 | €81.03 | €54.23 | €215.23 | €88.66 |
| Seller | Amazon | Amazon | Amazon | Amazon | Amazon | Amazon |
| 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
€68.87
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