Smart thermostat MEROSS MTS155MAT

• MEROSS MTS155MAT Smart Thermostat

The MEROSS MTS155MAT smart radiator thermostat lets you conveniently manage the temperature in your home, ensuring thermal comfort and helping to reduce unnecessary energy consumption.

The device uses Matter over Thread technology, allowing it to work with popular smart home systems such as Apple Home, Google Home, and Amazon Alexa.

It enables remote control of heating via an app and voice commands, as well as the creation of schedules tailored to your daily routine.

The open-window detection feature helps reduce energy loss, the heating history makes it easier to monitor costs, and automatic maintenance ensures the valve operates properly.

Thanks to the M30 × 1.5 connection and the 6 adapters included in the set, the thermostat fits many popular radiator valves.

• Smart Control with Matter over Thread

You can integrate the MEROSS MTS155MAT with various smart home systems and adjust the temperature using the app or voice commands directed at Siri, Alexa, and Google Assistant.

• You don’t have to go to the radiator to change the settings.

The device supports Thread 1.4 and Bluetooth 6.0 and does not require a dedicated Meross gateway.

However, to use Matter features, you’ll need a compatible Matter controller with a Thread edge router, such as the Apple HomePod mini, 4th-generation Amazon Echo, or 2nd-generation Google Nest Hub.

• A heating schedule tailored to your day

In the Meross app, you can set up a heating schedule that automatically adjusts the temperature according to the times you select.

Set a higher temperature for the morning and evening when you’re at home, and a lower one for when you’re away.

This ensures your rooms are heated according to your daily schedule, without the need to constantly adjust the thermostat manually.

It helps reduce energy consumption when intense heating isn’t necessary.

• Open Window Detection – Less Energy Loss

The MEROSS MTS155MAT thermostat is equipped with an open window detection feature that helps reduce energy loss while ventilating a room.

When you open a window, the device can automatically pause heating for a certain period of time.

This prevents the radiator from running unnecessarily while the room is being ventilated, helping you save energy without having to manually change the settings.

• Heating History and Cost Control

The Meross app lets you track the history of temperature changes, heating times, and valve positions.

Data presented in daily, weekly, monthly, and yearly views allows you to analyze heating performance and fine-tune your schedule.

Once you enter your heating rate, the app can also help estimate costs.

• This makes it easier to identify where you can save energy.
• Automatic Maintenance and Improved Design

The MEROSS MTS155MAT offers an automatic valve maintenance feature that can be enabled in the Meross app.

The device regularly performs a full cycle of opening and closing the valve, helping to prevent limescale buildup and mechanism jamming.

This ensures the valve operates smoothly and remains accurately calibrated.

Additionally, the reinforced design increases the thermostat’s durability, and the improved measurement accuracy helps maintain the set temperature.

• Wide Compatibility and Easy Installation

The thermostat is equipped with an M30 × 1.5 connector, and the kit includes 6 adapters: Danfoss RA, RAV, RAVL, Giacomini, Caleffi, and M28 × 1.5.

This allows the device to be installed on many popular radiator valves without having to replace the entire radiator.

The housing, measuring 8.2 × 5 × 5 cm, has a compact design, and power from two 1.5 V AA batteries eliminates the need for wiring.

• Batteries are not included.

Included in the set

• Danfoss RA adapter
• Danfoss RAV adapter
• Danfoss RAVL adapter
• M28 × 1.5 adapter
• Caleffi adapter
• Giacomini adapter
• User manual
• Model: MTS155MAT
• Device type: smart radiator thermostat
• Wireless connectivity: Thread 1.4, Bluetooth LE 6.0
• Technology: Matter over Thread
• Compatible Systems: Apple Home, Google Home, Amazon Alexa
• Control: App, voice commands
• Connector: M30 × 1.5
• Power Supply: 2 × 1.5 V AA batteries (not included, disposable batteries)
• Dimensions: 8.2 × 5 × 5 cm
• System Requirements: iOS 17 or later, Android 8.1 or later, Bluetooth 4.0 or later
• Matter requirements: Matter controller with a Thread edge router
• Operating temperature: 0°C to 40°C
• Storage temperature: -40°C to 70°C
• Operating humidity: 10–90% RH, non-condensing
• Storage humidity: 5–90% RH, non-condensing
• Net weight: 130
• Box length: 14,70
• Box width: 9,70
• Box height: 5,90
• About this product

The Meross MTS155MAT smart thermostat lets you conveniently manage the temperature in your home and reduce unnecessary energy consumption.

• Matter over Thread

The thermostat supports Matter over Thread, so it works with Apple Home, Google Home and Amazon Alexa.

You control it from the app or with voice commands for Siri, Alexa and Google Assistant.

• You don't have to go to the radiator to change settings.

Matter features require a compatible controller with a Thread border router.

• Heating schedule

In the Meross app you can set up a schedule that automatically changes the temperature at selected times.

You'll set a higher temperature in the morning and evening, when you are at home, and a lower one while you are away.

• Constantly adjusting the radiator by hand is not necessary.
• Open window detection

When a window is opened for ventilation, the thermostat can pause heating for a while.

The radiator then does not work unnecessarily, and the settings do not need to be changed manually.

You enable this function in the Meross app. The thermostat regularly performs a full cycle of opening and closing the valve, which is intended to prevent limescale buildup and mechanism blocking.

This maintenance supports smooth valve operation and maintains accurate calibration.

• Valve adapters

The thermostat has an M30 × 1.5 connector, and the set includes adapters for Danfoss RA, RAV and RAVL, Giacomini, Caleffi valves and M28 × 1.5.

This makes installation possible without replacing the entire radiator.

• Specifications

To use Matter features, however, you need a compatible Matter controller with a Thread border router, e.g. Apple HomePod mini, Amazon Echo 4th generation or Google Nest Hub 2nd generation.