Alarm.com Smart Thermostat HQ (ADC-T40K-HQ) - User Guide

Getting to know your Smart Thermostat

Your Smart Thermostat is designed to be intuitive and easy to use, whether you’re adjusting the temperature at home or managing settings from your phone.

Using the Smart Thermostat

Standby screen vs. Home screen

Your Smart Thermostat has two main display views: the Standby Screen and the Home Screen. Each screen serves a different purpose.

Standy screen

The Standby Screen appears when the thermostat is not actively being used.

It provides important information at a glance, including:

Current time
Current room temperature
Basic system status indicators (when applicable)

The Standby Screen is view-only and does not allow changes to thermostat settings.

Home screen

The Home Screen is the main control screen for your thermostat. It appears when you wake the thermostat by tapping the Standby Screen.

Here you’ll find essential controls and information:

Target (Set) Temperature - This is the large number in the middle of your screen and the temperature your system is working toward. You can adjust it using the up or down arrows on the screen or through the mobile app.
Current Room Temperature - This is the number in the bottom left of your screen. It reflects the temperature the thermostat is currently measuring in the room.
Humidity - In the bottom middle of your screen, this percentage reflects the humidity the thermostat is currently measuring in the room.
System Mode - In the bottom right of your screen, System Mode displays whether your system is set to:
- Heat
- Cool
- Auto (automatically switches
- between heating and cooling)
- Off
- Emergency (this mode is available only for systems with a heat pump)
Fan Setting - Shows whether the fan is set to Auto, On, or Circulate.
System Status - Messages such as Heating, Cooling, or Idle indicate what your system is doing at that moment.

Fan settings

Fan – Auto	The fan runs only when heating or cooling is actively occurring This is the most energy-efficient option Recommended for everyday use
Fan – On	The fan runs continuously, even when heating or cooling is not active Can help circulate air more evenly throughout the home May increase energy usage
Fan – Circulate	The fan runs automatically for a set amount of time each hour Helps move air throughout the home even when heating or cooling is not running Can support air circulation and filtration when used with a properly installed air filter

Navigating the thermostat menu

From the Home Screen, tap the Menu () icon in the top left to access additional controls and settings.

Menu options include:

Fan – Adjust fan operation
Wi-Fi – Adjust Wi-Fi settings
Settings – Adjust preferences such as display brightness and humidity
Installer – Install and maintenance settings for your service provider
Help – Contact information for your service provider

Using the Alarm.com Alarm.com app

Your Smart Thermostat works together with your smart home mobile app, allowing you to control your system from anywhere.

Overview of the Alarm.com app

Using the app, you can:

View your current room temperature and target temperature
Create and edit thermostat schedules
Adjust heating and cooling settings remotely
Change system modes (Heat, Cool, Auto, Off)
Control fan settings
Control additional compatible smart home devices
Receive alerts and notifications
View system activity and basic history

The app is designed to be simple and intuitive, with most actions requiring only a few taps.

Basic app navigation

When you open the Alarm.com app:

View your thermostat card on the main dashboard.
Click into the card to expand.
- Adjust the target temperature
- Change system mode
- Change fan mode
Access Schedule or Settings for additional options.

You can make manual adjustments at any time.

If a schedule is active, the thermostat will automatically return to it later.

Using thermostat schedules

Schedules allow your thermostat to automatically adjust temperatures throughout the day to match your routine and help manage energy use.

Common schedule examples include:

Warmer temperatures in the morning
Reduced heating or cooling while you’re away
Comfortable settings in the evening

To create or update a schedule:

Open the Alarm.com app and select your thermostat.
Tap Schedule.
Choose the days and times you want temperature changes to occur.
Set your desired temperatures.
Save your changes.

Schedules can be edited, paused, or turned off at any time. For more information about thermostat schedules, see Configure Thermostat Schedules.

For a video walkthrough on creating schedules, refer to Set up thermostat schedules.

Understanding alerts & notifications

Your Smart Thermostat can send alerts to help keep you informed about system operation and performance.

Alerts are intended to:

Provide insight into how your system is running
Notify you when something may need attention
Help distinguish between normal operation and potential issues

Types of alerts you may receive

Severe Heating or Cooling Alert	This alert means your system is running but is having difficulty reaching your set temperature. This can happen during extreme weather or when the system needs attention. If the alert persists, it may be time to contact your service provider for a system check.
Malfunction Alert	This alert means your thermostat has temporarily lost its internet connection. While your heating and cooling system will continue to operate normally, you won’t be able to control it through the mobile app until the connection is restored.
Temperature Alert	This alert means your home has reached an unusually high or low temperature. These alerts are designed to help protect your comfort and your home, including helping prevent issues like frozen pipes during cold weather.

How alerts are delivered

Alerts may appear:

In the mobile app
As push notifications (if enabled)
Via email communication

Alert preferences can be adjusted within the app settings.

For a video walkthrough on enabling push notifications in the Alarm.com app, refer to Enable Push Notifications.

Important Safety Information

Your Smart Thermostat uses a magnetic faceplate that can be easily removed.

Removing the faceplate exposes low-voltage (24V) wiring
Exposed wiring should not be touched
Do not remove the faceplate unless directed by a qualified professional

Do not attempt to service, rewire, or adjust internal components yourself. Always contact your service provider for assistance.

System Compatibility & What’s Included

Your Smart Thermostat is compatible with most common residential HVAC systems and operates using standard 24V power. It supports features such as smart scheduling, humidity control, and mobile app connectivity, depending on system configuration.

Need Help?

If you have questions about your thermostat, mobile app, alerts, or system behavior, contact your service provider.