1. Introduction
This manual provides essential information for the safe and efficient operation of your ALORAIR Sentinel HDi120 Commercial Dehumidifier. Please read all instructions carefully before installation and use. Retain this manual for future reference.

Figure 1: ALORAIR Sentinel HDi120 Dehumidifier
The ALORAIR Sentinel HDi120 is a high-capacity dehumidifier designed for various applications, including crawl spaces, basements, warehouses, and commercial spaces up to 3,300 sq. ft. It features a robust metal construction, an internal condensate pump, and automatic defrost capabilities.
2. Safety Information
Always follow basic safety precautions to reduce the risk of fire, electric shock, or injury. This unit is designed for indoor use only. Do not operate the unit with a damaged power cord or plug. Ensure proper grounding. Do not block air inlets or outlets. Refer to the full safety guidelines in the printed manual for comprehensive details.
3. Setup and Installation
3.1 Unpacking and Placement
Carefully remove the dehumidifier from its packaging. Inspect the unit for any shipping damage. Place the unit on a level surface in the desired location. The compact size (23.8"D x 14.7"W x 17.9"H) allows for placement in various tight spaces.

Figure 2: Dehumidifier Dimensions
3.2 Power Connection
Connect the provided power cord to a grounded 115V AC outlet. The unit operates at 7.8A and 897 Watt-hours.
Video 1: ALORAIR Sentinel HDi120 Overview. This video demonstrates the unit's features and power connection.
3.3 Drainage Setup
The Sentinel HDi120 features a built-in condensate pump for automatic drainage. Connect the drain hose to the unit's drain port. The pump can lift water up to 14.7 feet vertically, allowing for flexible drainage options.

Figure 3: Built-in Condensate Pump
3.4 Optional Remote Control Installation
An optional remote controller can be used to manage the dehumidifier from a distance. Connect the remote controller to the unit using a CAT 5 cable. Ensure the remote controller's mode is correctly set (Series 2 for this model) by adjusting the jumper cap on the circuit board.
Video 2: Optional Remote Controller Mode Switching Guide (Series 2). This video demonstrates how to switch the mode of the remote controller.
Video 3: How to Use Remote Controller. This video provides instructions on installing and using the remote controller.
3.5 Optional Air Duct Installation
For specific applications, the dehumidifier can be ducted. Install the duct mounting plate and secure the flexible air duct with a strap. This allows for directing dry air to specific areas or integrating with existing HVAC systems.
Video 4: How to install the air duct for Sentinel HDi120 Dehumidifier. This video demonstrates the process of installing the air duct.
4. Operating Instructions
4.1 Control Panel Overview
The unit features an easy-to-use touch button control panel. The display shows the current humidity level. Indicators for Power, Compressor (Comp), Drain, and Continuous Defrost (Cont.Defrost) are present.

Figure 4: Intuitive Control Panel
4.2 Setting Desired Humidity
Use the 'Up' and 'Down' arrow buttons on the control panel to set your desired humidity level. The unit will operate to maintain this set point. Once the target humidity is reached, the unit will cycle off and restart when humidity rises.
4.3 Continuous Mode
The unit can be set to continuous operation mode, where it will run constantly regardless of the humidity level, providing maximum dehumidification.
4.4 Automatic Defrost
The advanced auto-defrosting system continuously monitors ambient temperature. If low temperatures are detected, the unit initiates an automatic defrost cycle to prevent frost buildup on the coils. During this cycle, the compressor pauses while the fan continues to run. Once defrosting is complete, normal operation resumes.

Figure 5: Auto Defrost Function
5. Maintenance
5.1 Filter Replacement
The dehumidifier uses MERV-1 and MERV-10 filters. The high-density filter protects internal components from dust damage. Replace the MERV-1 filter every 3-6 months and the MERV-10 filter every 2-3 months, depending on air quality.

Figure 6: Filter Access
Video 5: How to replace Sentinel HDi120 dehumidifier filter. This video guides you through the filter replacement process.
5.2 Coil Cleaning
Regular cleaning of the dehumidifier coils is crucial for maintaining efficiency. Follow the steps in the video to clean the coils using a coil cleaner and water. Avoid using acid cleaners or hard tools that could damage the coil surface.
Video 6: How to clean dehumidifier coils for Sentinel HDi120. This video provides a step-by-step guide for cleaning the coils.
5.3 Operation Screen Replacement
If the operation screen needs replacement, follow the detailed instructions provided in the video. This involves carefully removing the side panel, disconnecting the old screen, and installing the new one.
Video 7: How to Replace the operation screen for Sentinel HDi120. This video demonstrates the replacement procedure for the operation screen.
6. Troubleshooting
If the unit is not operating as expected, perform the following basic checks:
- No Power: Ensure the power cord is securely plugged into a functional outlet. Check the circuit breaker.
- Not Dehumidifying: Verify that the desired humidity setting is lower than the current room humidity. Check if the air filter is clean and not obstructed. Ensure the unit is not in defrost mode.
- Water Leakage: Inspect the drain hose for kinks, blockages, or improper connection. Ensure the unit is on a level surface.
- Unusual Noise: Check for any loose parts or obstructions in the fan area.
For persistent issues, contact customer support.
7. Specifications
| Feature | Specification |
|---|---|
| Brand | ALORAIR |
| Model Name | Sentinel HDi120 |
| Floor Area Coverage | Up to 3300 Square Feet |
| Dehumidification Capacity | 235 Pints/Day (Saturation), 120 PPD (AHAM) |
| Product Dimensions | 23.8"D x 14.7"W x 17.9"H |
| Item Weight | 88 Pounds |
| Voltage | 115 Volts (AC) |
| Wattage | 897 Watt-hours |
| Air Flow Capacity | 290 Cubic Feet Per Minute (CFM) |
| Operation Mode | Condensate Pump |
| Special Features | Automatic Defrost, Automatic Restart, Microchannel Condenser Technology, MERV-1 & MERV-10 Filter |
| Material | Metal |
| Color | White |
8. Warranty Information
The ALORAIR Sentinel HDi120 Commercial Dehumidifier comes with a 5-year limited warranty. This warranty covers:
- 6 Months: Parts and labor, including shipment charges for replacement parts or unit.
- 1 Year: Parts and labor, excluding shipment charges to send the defective product back for repair or replacement.
- 3 Years: Parts and labor coverage for the refrigeration system only.
- 5 Years: Compressor and coil.
For additional warranty information or to make a claim, please refer to the official ALORAIR website or contact customer support.
9. Customer Support
For technical assistance, troubleshooting, or warranty inquiries, please contact ALORAIR customer support:
- Website: www.alorair.com
- Email: support@alorair.com
- Phone: (Toll-Free number, if available, would be listed here)
Please have your model number (Sentinel HDi120) and purchase date ready when contacting support.





