Ecobee ecobee3 2nd Gen Remote vs Ecobee Smart Thermostat SmartSensor (2026): Key Differences
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When you compare the ecobee smart thermostat vs ecobee3 smarter wi fi thermostat, you see two devices built for home comfort. Both use Wi-Fi to connect and include remote sensors to track occupancy. The main difference lies in their feature sets. The newer Premium model adds air quality monitoring, voice assistant integration, and a video doorbell interface. The older ecobee3 focuses on core heating and cooling control with Alexa compatibility.
Key differences
| Aspect | Ecobee Smart Thermostat Premium with SmartSensor | Ecobee ecobee3 2nd Gen with Remote Sensor |
|---|---|---|
| Smart Home Compatibility | Siri, Alexa | Alexa |
| Sensor Support | SmartSensor, air quality, occupancy | Remote Sensor, occupancy |
| Wiring Requirement | PEK included for homes without C-wire | not listed |
| Display | Large, vibrant display | not listed |
Which one should you choose?
Choose Ecobee Smart Thermostat Premium with SmartSensor if
- You want built-in voice control with Siri or Alexa
- You need air quality monitoring and alerts
- Your HVAC system lacks a C-wire and you need the included Power Extender Kit
Choose Ecobee ecobee3 2nd Gen with Remote Sensor if
- You prefer a simpler device with basic Alexa support
- You only need standard occupancy sensing for comfort
- You want a compact unit with a smaller footprint
Verdict: The Ecobee Smart Thermostat Premium is the better choice if you want advanced features like air quality tracking and dual voice assistant support. The ecobee3 2nd Gen remains a solid option for users who only require core thermostat functions and Alexa integration. Your decision depends on whether you need the extra monitoring and connectivity of the newer model.
Premium vs ecobee3 Key Differences
Smart Home Compatibility
The Ecobee Smart Thermostat Premium includes built-in support for both Siri and Alexa. You can control your home by voice directly through the device without needing separate hubs for either ecosystem. The ecobee3 2nd Gen Remote supports Alexa, but requires a separate Alexa device. It does not list native Siri integration. If you use Apple HomeKit or Siri shortcuts, the Premium model offers a more integrated experience. For Alexa-only users, both devices handle voice commands, though the Premium unit has the speaker built in.
Air Quality Monitoring
The Ecobee Smart Thermostat Premium features a built-in air quality monitor. It provides alerts when air quality drops, offers tips to improve it, and reminds you to change furnace filters. The ecobee3 2nd Gen Remote does not list any air quality sensors or monitoring capabilities in its specifications. If indoor air health is a priority, the Premium model provides active tracking and notifications. The ecobee3 focuses solely on temperature and occupancy data without environmental quality feedback.
Display and Interface
The Ecobee Smart Thermostat Premium has a large, vibrant display with a cinematic interface. It uses an elegant metal finish and detects when you are home to adjust comfort automatically. The ecobee3 2nd Gen Remote has a standard display, but the data does not specify its size or resolution compared to the Premium model. The Premium unit offers a more modern visual experience. The ecobee3 provides basic temperature control visibility. For users who prefer a sleek, high-resolution screen, the Premium model is the superior choice.
Wiring and Installation
The Ecobee Smart Thermostat Premium includes a Power Extender Kit (PEK) for homes without a C-wire. It also includes a Trim Kit for a clean finish. The ecobee3 2nd Gen Remote data does not explicitly list included installation accessories like a PEK or Trim Kit. Both devices require Wi-Fi connectivity. If your home lacks a common wire, the Premium model provides the necessary hardware out of the box. The ecobee3 may require separate purchase of adapters for similar installation scenarios.
Security and Monitoring
The Ecobee Smart Thermostat Premium can listen for smoke alarm sounds and send alerts if one is detected. It also supports streaming live video from an ecobee Smart Doorbell Camera. The ecobee3 2nd Gen Remote does not list smoke alarm detection or camera streaming capabilities. If you want your thermostat to assist with home security and emergency alerts, the Premium model offers these features. The ecobee3 focuses on comfort and occupancy without these additional safety integrations.
Which ecobee thermostat fits your home
Users wanting air quality and security
The Premium model includes a built-in air quality monitor that alerts you when filtration is needed. It also supports video doorbells and smoke alarm detection. If you want comprehensive home monitoring alongside temperature control, this device offers the necessary hardware and sensor support for a complete smart home experience.
Voice control enthusiasts using Siri
This thermostat features built-in Siri and Alexa support, allowing direct voice control without separate hubs. The ecobee3 2nd Gen only works with Alexa. If you rely on Apple HomeKit or want to stream music through the thermostat’s speaker, the Premium model provides the integrated smart speaker capabilities you need.
Renters needing simple occupancy sensing
The ecobee3 2nd Gen Remote offers essential occupancy sensing and Wi-Fi connectivity at a lower complexity. It detects when you are home and adjusts heating or cooling accordingly. If you do not need air quality monitoring or video features, this older model provides the core comfort and energy-saving functions you require.
The products compared
Ecobee Smart Thermostat Premium with SmartSensor
Best for: homes needing room-specific comfort and air quality monitoring
- System Compatibility
- 95% of HVAC systems
- Wiring Requirement
- Power Extender Kit (PEK) / C-wire
- Smart Home Compatibility
- Alexa, Siri, Google Home
- Sensor Support
- SmartSensor, air quality, occupancy
- Connectivity
- Wi-Fi
- Dimensions
- 1.02 × 4.09 × 4.09 inches
View on Amazon: Ecobee Smart Thermostat Premium with SmartSensor Affiliate link
The ecobee Smart Thermostat Premium combines WiFi connectivity with built-in Siri and Alexa support. It includes a SmartSensor to detect occupancy in specific rooms, reducing hot or cold spots. A built-in air quality monitor tracks your environment and alerts you when filters need changing. This ENERGY STAR certified unit features a large display and metal finish, designed for DIY installation with a Power Extender Kit included.
Pros
- Built-in Siri and Alexa smart speaker support
- Includes SmartSensor for room-specific occupancy detection
- Integrated air quality monitor with filter alerts
- Power Extender Kit included for C-wire-less homes
Cons
- Requires Apple home hub for full Siri functionality
- Smoke alarm detection needs ecobee Smart Security subscription
- Higher price point compared to standard models
Good fit if
- You want voice control via Siri or Alexa directly on the device
- You need to manage temperature differences between specific rooms
- You want to monitor indoor air quality and filter status
Skip if
- You do not have an Apple home hub for Siri integration
- You are looking for a basic thermostat without air quality monitoring
- You prefer a smaller device with a simpler interface
Verdict: Ecobee Smart Thermostat Premium with Sensor is ideal for users seeking comprehensive climate control with voice assistant integration and air quality monitoring. It suits homes where room-specific comfort and detailed environmental data are priorities.
Ecobee ecobee3 2nd Gen with Remote Sensor
Best for: homes needing room-specific temperature control
- Smart Home Compatibility
- Alexa
- Sensor Support
- Remote Sensor, occupancy
- Connectivity
- Wi-Fi
- Dimensions
- 3.95 × 3.95 × 0.93 inches
- Weight
- 1.35 pounds
View on Amazon: Ecobee ecobee3 2nd Gen with Remote Sensor Affiliate link
The Ecobee3 2nd Gen is a universal Wi-Fi thermostat with a black finish. It measures 3.95 by 3.95 inches and weighs 1.35 pounds. It supports remote occupancy sensors to detect which rooms are in use. This allows the system to adjust heating or cooling based on actual presence. It integrates with Alexa for voice control. You get smart scheduling that learns your home's energy profile and weather patterns.
Pros
- Supports remote occupancy sensors for room-specific comfort
- Wi-Fi connectivity for remote management
- Alexa voice control compatibility
- Universal size fits most installations
Cons
- Alexa device sold separately
- No mention of Apple HomeKit or Google Assistant support
- No mention of built-in air quality monitoring
Good fit if
- You want to use remote sensors to balance temperature in different rooms
- You already own an Alexa device for voice control
- You prefer a black universal thermostat
Skip if
- You need built-in air quality sensors
- You want native support for Apple HomeKit or Google Assistant
- You do not want to purchase a separate Alexa device
Verdict: Ecobee3 2nd Gen Wi-Fi Thermostat with Remote Sensor is a solid choice if you want room-level comfort control via remote sensors and already use Alexa. It suits homes where you want to target heating or cooling only to occupied areas.
Specifications side by side
| Spec | Ecobee Smart Thermostat Premium with SmartSensor | Ecobee ecobee3 2nd Gen with Remote Sensor |
|---|---|---|
| System Compatibility | 95% of HVAC systems | not stated |
| Wiring Requirement | Power Extender Kit (PEK) / C-wire | not stated |
| Smart Home Compatibility | Alexa, Siri, Google Home | Alexa |
| Sensor Support | SmartSensor, air quality, occupancy | Remote Sensor, occupancy |
| Connectivity | Wi-Fi | Wi-Fi |
| Dimensions | 1.02 × 4.09 × 4.09 inches | 3.95 × 3.95 × 0.93 inches |
| Weight | 1.32 pounds | 1.35 pounds |
| Size | 2.9 x 4.09 x 4.09 inches | Universal |
| Color | Black | Black |
| Model | EB-STATE6-01 | EB-STATe3-O2 |
Frequently asked questions
Does the ecobee3 2nd Gen include a remote sensor?
Yes, the ecobee3 2nd Gen comes with a remote sensor. This allows you to place the sensor in rooms where you spend the most time. The thermostat then uses that data to prioritize comfort in occupied areas. This helps balance temperatures across your home more effectively than relying on a single thermostat location.
What is the size difference between the two thermostats?
The Ecobee Smart Thermostat Premium measures 4.09 inches wide and 4.09 inches tall. The ecobee3 2nd Gen is slightly narrower at 3.95 inches wide and 3.95 inches tall. Both devices have a similar depth profile, with the Premium being 1.02 inches thick and the ecobee3 being 0.93 inches thick. The weight also differs slightly.
Can I use voice commands with the ecobee3 2nd Gen?
Yes, the ecobee3 2nd Gen supports Alexa. You can control your thermostat using voice commands if you have an Alexa-enabled device. However, it does not have built-in Siri support like the Premium model. You will need to use the Alexa ecosystem for voice integration with this specific thermostat model.
Is the Premium model better for air quality monitoring?
Yes, the Ecobee Smart Thermostat Premium includes an air quality monitor. This feature alerts you when your filtration system needs attention. The ecobee3 2nd Gen does not have this capability. If tracking indoor air quality is important to you, the Premium model provides that specific environmental data directly on the device.
Do both thermostats connect via Wi-Fi?
Yes, both the Ecobee Smart Thermostat Premium and the ecobee3 2nd Gen connect via Wi-Fi. This allows you to control them remotely through your smartphone or tablet. You can adjust temperatures and view status from anywhere with an internet connection. Both devices rely on this wireless connection for smart features and remote access.
Which thermostat is heavier?
The ecobee3 2nd Gen weighs 1.35 pounds. The Ecobee Smart Thermostat Premium weighs 1.32 pounds. The difference is minimal, but the ecobee3 2nd Gen is slightly heavier. Both units are designed to be mounted on your wall, so the weight difference is unlikely to affect installation or stability on most standard walls.
Does the Premium model support video doorbells?
Yes, the Ecobee Smart Thermostat Premium supports video doorbells. This allows you to see who is at your door using the thermostat display. The ecobee3 2nd Gen does not list this compatibility. If you want to integrate your doorbell camera directly with your climate control interface, the Premium model offers this specific feature.