
Alarm.com Smart Thermostat
Score: 78/100
ecobee3 Smarter
Score: 84/100Rankings

The ecobee3 Smarter thermostat provides a 3.5-inch color touchscreen and a suite of built-in sensors for precise climate control, along with broad 24 V HVAC compatibility and optional Power Extender Kit. It requires a C-wire or additional kit and uses older 2.4 GHz Wi-Fi, which may limit some setups. Best suited for users wanting multi-zone sensing and Apple ecosystem integration.

The Alarm.com Smart Thermostat is a Z-Wave-enabled thermostat featuring a high-resolution color touchscreen and machine-learning HVAC health monitoring. Its main drawbacks are the required Alarm.com subscription, mandatory C-wire, and a limited operating temperature range. It is best suited for existing Alarm.com security customers who want deep integration and humidity control.
| Attribute | ![]() | ![]() |
|---|---|---|
— | 3 yearsbest | |
— | 3.5 inchbest | |
| ↓ lower better | 0.14 kgbest | 0.612 kg |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
General(1) | ||
HVAC Compatibility | Heat up to 3 stages, Cool up to 2 stages, Heat pump (O/B), Fan (G), Humidifier/dehumidifier/vent (Z1/Z2 configurable) | ~95% of 24V systems (conventional 2H/2C, heat pump 4H/2C, gas/oil/electric/dual fuel, humidifier/dehumidifier/ventilator/HRV/ERV) |
Connectivity(1) | ||
Smart Home Integration | Alarm.com, Z-Wave | Apple HomeKit, Amazon Alexa, Google Assistant |
Build & Design(2) | ||
Device Weight (kg) | 0.14 kg | 0.612 kg |
Device Dimensions (H×W×D) (mm) | 50.8×203.2×203.2 mm mm | 23.6×100.3×100.3 mm mm |


Products in the top-left offer the best value (high score, low price).

Professional reviewers highlight the thermostat's seamless integration with Alarm.com, noting the built-in Z-Wave hub reduces hardware clutter and the machine-learning HVAC monitoring provides valuable early-warning alerts. They also praise the sleek touchscreen design and straightforward installation, while cautioning that the product requires an Alarm.com service subscription and has a limited temperature operating range.
Everyday users appreciate the convenience of remote app control, real-time alerts, and the ability to manage humidity, but they commonly express frustration over the mandatory C-wire requirement and the need for an ongoing Alarm.com subscription to unlock full features.

Professional reviewers commend the Ecobee3 for its comprehensive sensor suite that enables smart recovery and precise humidity management, as well as its extensive HVAC compatibility that covers most 24V systems. They note its value for multi-zone comfort without a hub, while pointing out the need for a C-wire or Power Extender Kit and the lack of newer Wi-Fi standards compared to later models.
Everyday users praise the thermostat for its straightforward installation and reliable Wi-Fi control, especially appreciating the seamless Siri and HomeKit integration. The most common feedback revolves around occasional wiring difficulties in homes without a C-wire, but overall sentiment is highly positive.
“ease of install and Wi-Fi control”

“seamless Siri/HomeKit remote access”

