Emerson Sensi ST55
Score: 72/100
ecobee Smart Thermostat Enhanced
Score: 86/100Rankings
The ecobee Smart Thermostat Enhanced delivers up to 26% energy savings, geofencing and radar occupancy detection with a vibrant 4-inch touchscreen. It lacks air-quality monitoring and multi-zone support, which may limit advanced users. Ideal for single-zone homeowners seeking strong energy-saving features and wide smart-home integration.
Emerson Sensi ST55 provides a 5-inch LED touchscreen, broad smart-home compatibility, and geofencing-driven energy savings, all at an affordable price. Limitations include the need for a C-wire, 2.4 GHz-only Wi-Fi, and lack of built-in room sensors. Ideal for DIY homeowners seeking a versatile, budget-friendly thermostat.
| Attribute | | |
|---|---|---|
3 yearsbest | 3 yearsbest | |
5 inchbest | 4 inch | |
| ↓ lower better | 0.386 kg | 0.24 kgbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | | |
|---|---|---|
General(1) | ||
HVAC Compatibility | Various (single to multi-stage) | 24 VAC systems (gas/oil/electric furnaces, dual fuel, forced air, heat pump, boilers) |
Connectivity(1) | ||
Smart Home Integration | Alexa, Google Assistant, Apple HomeKit, Samsung SmartThings | Siri, Alexa, Google Assistant, Apple HomeKit, SmartThings, IFTTT |
Power & Installation(2) | ||
C‑Wire Requirement | true | false |
Power Source | 20-30 VAC | HVAC system wiring with optional Power Extender Kit |
Display(1) | ||
Screen Size (inch) | 5 inch | 4 inch |
Build & Design(2) | ||
Device Weight (kg) | 0.386 kg | 0.24 kg |
Device Dimensions (H×W×D) (mm) | 25.4×149.35×95.25 mm mm | 103.89x103.89x23.88 mm |
Products in the top-left offer the best value (high score, low price).
Professional reviewers commend the Sensi ST55 for its straightforward DIY installation, ENERGY STAR efficiency and the claimed 23% energy savings, as well as its compliance with Title 24 and robust smart-home integration. However, they point out the need for a c-wire to unlock full functionality and the limitation to a 2.4 GHz Wi-Fi band.
Homeowners and renters alike praise the thermostat's quick setup, remote app control, energy-saving reports, and reliable fan circulation. Recurring complaints focus on occasional Wi-Fi drops, the necessity of a c-wire for some systems, and the lack of a built-in room sensor or precise humidity control.
“Very user-friendly with many features; compact and attractive on the wall; effortless control and energy savings (pays for itself quickly).”
Professional reviewers commend the Enhanced model for its proven energy-efficiency, radar-based occupancy detection and extensive voice-assistant integrations, calling it a trusted, planet-friendly choice. They note, however, that it misses premium features such as air-quality monitoring and bundled remote sensors, and that installation can be a bit daunting for novices.
Everyday users appreciate the thermostat's intuitive touchscreen, sleek compact look and the quick payoff from energy savings, describing it as very user-friendly. Common frustrations revolve around the need to follow detailed setup instructions and the lack of extra sensors found in higher-end models.
