Alarm.com Smart Thermostat HQ (ADC-T40K-HQ) - Data Sheet
Overview
The Smart Thermostat HQ expands the award-winning Smart Thermostat HD with a powerful built-in Hub that seamlessly controls other smart home devices. With no need to install a separate Hub, the Smart Thermostat HQ simplifies installations, reduces costs, and uses less space in the home.
The Smart Thermostat HQ offers a dedicated cellular connection and broadband backup to ensure reliable performance and supports SmartStart so devices can be quickly and easily added to the smart home.

In the box
- ADC-T40 thermostat
- ADC-T40-HQ touchscreen display
- Drywall anchors and screws (x2)
- Trim plate
Features
- Smart home controller
- Setup wizard
- Touchscreen display
- Wire detection and auto-configuration
- Humidity control
- Ventilation control
- Cellular and Wi-Fi connection
- Z-Wave SmartStart and S2 compatible
- Display Sync for separated thermostat installation
- Full integration with the Alarm.com platform
Terminal guide
| Terminal | Description |
|---|---|
| RC | Cooling Power |
| RH | Heating Power – Required Wire |
| W2 | Heat/Aux Stage 2 |
| W | Heat/Aux Stage 1 |
| C | Common wire from transformer for RH – Required Wire |
| Z1 | Configurable: W3, Humidifier, Dehumidifier, Vent |
| Z2 | Configurable: W3, Humidifier, Dehumidifier, Vent |
| Y | Cool/Pump Stage 1 |
| Y2 | Cool/Pump Stage 2 |
| G | Fan |
| O | Heat Pump Reversing Valve (Energized in COOL mode) |
| B | Heat Pump Reversing Valve (Energized in HEAT mode) |
Specifications
| Power | 24 VAC |
|---|---|
| Dimensions (H x W x D) | 4.7 x 4.7 x 1.07’’ (12 x 12 x 2.72 cm) |
| Operating Temperature | 41°F to 95°F (5°C to 35°C) |
| Cellular Carrier Options | Verizon and AT&T |
| Optional Wi-Fi | Yes |
| Communication | Z-Wave |
Compatible systems
| Near universal 24 V compatibility | Yes |
|---|---|
| Humidifier/Dehumidifier | Yes |
| Forced air | Yes |
| Heat pump | Yes |
| Heat | Up to 3 stages |
| Cool | Up to 2 stages |
| Dual fuel | Yes |
| Ventilation control | HRV, ERV, external air baffle |
| Dual Power Supply Systems | Yes |