10 Best Line Voltage Thermostats 2026 in the United States

The Mysa Smart Thermostat LITE is a solid choice for anyone looking to upgrade their line-voltage electric baseboard or wall heaters with smart control. It supports a wide voltage range from 120V to 240V, making it compatible with most residential electric heating systems. Although it works with both single and double pole wiring setups, it can only be installed as a single-pole thermostat, which is common but something to check for your specific heater. Its temperature range and control are managed through an easy-to-use app, allowing you to program schedules, adjust settings remotely, and even use voice assistants like Apple HomeKit, Alexa, or Google Assistant for convenient hands-free operation. The included LCD display provides clear temperature feedback, and the minimalist design fits well in modern homes.

Installation is straightforward with a 4-wire setup and helpful video guides, making it approachable for DIY users without needing an electrician. Additional features like geofencing, vacation mode, and energy reports help save on heating costs by tailoring usage to your lifestyle. On the downside, since it lacks a double-pole operating mode, it might not suit every electric heater configuration, and its app-only control might feel limiting if you prefer physical buttons over touch or voice controls.

The product is well-built with a two-year warranty and UL certification, making it reliable for long-term use in places like garages, workshops, or sunrooms where electric heating is common. For those seeking a smart, programmable, and energy-saving thermostat for line-voltage electric heaters, Mysa's LITE model offers a great balance of features and ease of use.

The Mysa Smart Thermostat is designed specifically for high-voltage electric in-floor heating systems, supporting 120-240V and offering built-in Class A GFCI protection, which adds safety by reducing the risk of electrical faults. This makes it a good choice if you have a line-voltage system and want to upgrade to a smart thermostat. It is not compatible with water-based heating systems, so it’s important to ensure your heating matches this type.

The thermostat is fully programmable via a free mobile app, letting you control temperature remotely through Wi-Fi using Apple HomeKit, Alexa, or Google Home. This adds convenience and energy savings by allowing you to adjust settings anytime without manual intervention. The display is LED-backlit with touch controls on the unit itself, providing a modern look and easy interaction. Unlike some models, Mysa does not require a subscription for its smart features, which is a nice cost-saving bonus. It includes useful extras like vacation mode, daylight savings time adjustments, and lockable controls for safety.

Installation is relatively straightforward, with included mounting hardware and floor sensor. The product is somewhat specialized: it’s intended only for electric in-floor heating, so it won't fit other heating types or lower voltage requirements. If you are looking for a smart, reliable thermostat for electric floor heating with modern app integration and safety features, Mysa is a strong option. Just be sure your system voltage and heating type are compatible before choosing it.

The KING K902-W Hoot WiFi Line Voltage Smart Programmable Thermostat is a versatile option for those using electric baseboard, fan-forced, or radiant heaters. Its double-pole, 4-wire installation provides robust safety by completely disconnecting power when switched off. This model is compatible with multiple voltages (120/208/240V), making it flexible for different home setups.

The thermostat is programmable using the Hoot smartphone app, allowing users to set up to six time periods per day, which is ideal for those who want control over their energy usage and comfort levels. Its large LCD touchscreen is user-friendly, and the Wi-Fi connectivity adds convenience for remote adjustments. The thermostat's temperature range of 41º - 90ºF suits most household needs, and the electronic sensing offers accurate temperature control within ±1ºF.

A notable feature is the over-the-air firmware upgrades, ensuring the device stays up-to-date with the latest technology. Some users may find the setup process challenging, especially if they are not familiar with wiring or using smartphone apps for device controls. Despite these drawbacks, the KING K902-W is a modern thermostat with good programmability and flexibility, suitable for tech-savvy individuals who want enhanced control over their heating systems.