Aqualung i550 Dive Computer User Manual

Introduction

The Aqualung i550 is a robust and versatile dive computer designed for both new and experienced divers. It features a large, easy-to-read display and offers three primary operating modes: Air, Nitrox, and Gauge. Key functionalities include gas integration for real-time tank pressure and gas time remaining, user-changeable battery, backlighting for low-light conditions, and audible alarms with high-visibility LED warnings. This manual provides essential information for the proper setup, operation, maintenance, and troubleshooting of your i550 dive computer.

Safety Information

Always prioritize safety during diving activities. The i550 dive computer is an aid to safe diving, but it does not replace proper dive training, experience, or the need for careful dive planning. Always adhere to the following guidelines:

• Read the Entire Manual: Familiarize yourself with all features and warnings before your first dive.
• Dive Training: Ensure you are properly trained and certified for all types of diving you undertake.
• Backup Instruments: Always carry backup depth and timing devices.
• Pre-Dive Checks: Perform all necessary pre-dive checks, including battery level, gas settings, and alarm functions.
• Decompression Limits: Understand and adhere to no-decompression limits. Never intentionally enter decompression.
• Ascent Rate: Maintain a safe ascent rate as indicated by the computer.
• Health: Do not dive if you are feeling unwell or under the influence of alcohol or drugs.

Setup

1. Unpacking and Initial Inspection

Upon receiving your Aqualung i550, carefully unpack all components. Verify that the dive computer unit, quick disconnect mechanism, and any included accessories such as the USB download cable (if part of a Pro Pack) are present and undamaged.

2. Battery Installation

The i550 features a user-changeable battery. Refer to the battery compartment on the back of the unit. Use a coin or appropriate tool to open the compartment. Insert a fresh battery, ensuring correct polarity. Close the compartment securely to maintain water integrity. The i550 retains settings and calculations during battery changes.

3. Initial Configuration

After battery installation, the i550 will prompt you for initial setup. Follow the on-screen instructions to set the following:

• Time and Date: Set the current time and date.
• Units: Select preferred units (e.g., metric or imperial for depth, temperature, and pressure).
• Dive Parameters: Configure default settings for conservatism, alarms, and other dive-specific preferences.

4. Quick Disconnect Attachment

The i550 is designed with an optional quick disconnect feature for convenient storage and hose management. To attach the quick disconnect, align the male end of the dive computer console with the female end of the high-pressure hose. Push firmly and twist until it clicks securely into place. Ensure a tight seal before diving.

Image: The Aqualung i550 dive computer console showing the quick disconnect mechanism. The red arrow indicates the twisting motion required to connect or disconnect the unit from the high-pressure hose.

To detach, reverse the process by twisting and pulling the quick disconnect. Always ensure the system is depressurized before attempting to disconnect.

Image: The Aqualung i550 dive computer console with the quick disconnect fully attached to the high-pressure hose, ready for use. A faint outline of the disconnected unit is visible in the background.

5. USB Download Cable Connection

If you have the optional USB download cable, connect it to the designated port on your i550 and to your computer. This cable is used for downloading dive logs and updating the computer's firmware. Ensure the connection is secure before transferring data.

Operating Modes

The i550 offers three distinct operating modes to suit various diving needs:

1. Air Mode

In Air Mode, the i550 calculates decompression limits and displays relevant dive data based on diving with standard air (21% oxygen). This is the default mode for most recreational dives.

2. Nitrox Mode

Nitrox Mode allows you to dive with enriched air nitrox (EAN). Before diving in Nitrox Mode, you must accurately set the oxygen percentage (O₂%) of your gas mixture. The i550 will then calculate no-decompression limits and maximum operating depth (MOD) based on your specified O₂% and a default partial pressure of oxygen (PO₂) limit.

3. Gauge Mode

Gauge Mode functions as a bottom timer, displaying current depth, maximum depth, and dive time. It does not provide decompression information or tissue loading calculations. This mode is suitable for technical diving where decompression is planned manually or with other instruments.

4. Gas Integration

The i550 features gas integration, allowing it to display your tank pressure directly on the screen. Utilizing a patented Gas Time Remaining (GTR) algorithm, the computer provides real-time calculations of your remaining dive time based on your current depth, breathing rate, and tank pressure. This aids in accurate gas management throughout your dive.

5. Backlighting

For enhanced visibility in low-light conditions or night dives, the i550 is equipped with a backlight feature. Activate the backlight as needed to clearly read your dive data.

6. Audible Alarms and LED Warnings

The i550 incorporates audible alarms and a high-visibility LED warning light to alert you to critical dive parameters. These warnings may include rapid ascent rates, exceeding no-decompression limits, low gas pressure, or other user-defined alerts. Pay immediate attention to any activated alarms.

Maintenance

1. Battery Replacement

When the low battery indicator appears, replace the battery promptly. Always use a new, high-quality battery of the specified type. Ensure the O-ring seal is clean and properly seated, and apply a thin layer of silicone grease if necessary, before securely closing the battery compartment. Improper battery replacement can compromise the unit's water resistance.

2. Cleaning and Storage

After each dive, rinse your i550 thoroughly with fresh water to remove salt, sand, and other debris. Allow it to air dry completely in a shaded area. Store the dive computer in a cool, dry place away from direct sunlight and extreme temperatures. Avoid exposing the unit to harsh chemicals or solvents.

3. Software Updates

Aqualung periodically releases software updates to enhance features or improve performance. Connect your i550 to a computer using the USB download cable and use the Aqualung software to check for and install available updates. Keeping your software current ensures you have access to the latest functionalities.

Troubleshooting

This section addresses common issues you might encounter with your i550 dive computer.

• Blank or Unresponsive Display: Check the battery level. If the battery is low or depleted, replace it. Ensure the battery is installed with correct polarity and the compartment is securely closed. If the issue persists, contact customer support.
• Rapid Battery Drain: If your i550 experiences unusually fast battery depletion, ensure it is properly entering sleep mode after the surface interval. If the issue continues even with new batteries, there may be an internal fault. Contact Aqualung customer support for assistance.
• Inaccurate Compass Readings: Dive computer compasses can sometimes be affected by magnetic interference or require calibration. Try calibrating the compass according to the instructions in the full Aqualung manual. For critical navigation, always rely on a dedicated, properly calibrated external compass.
• Temperature Reading Discrepancy: Minor variations in temperature readings between different dive computers are possible due to sensor placement and environmental factors. If you suspect a significant discrepancy, compare with a known accurate thermometer.
• Data Download Issues: Ensure the USB cable is securely connected to both the i550 and your computer. Verify that the Aqualung software is correctly installed and updated. Try restarting both the computer and the dive computer.

Specifications

Warranty Information

The Aqualung i550 Dive Computer typically comes with a 2-year limited warranty from the date of purchase. This warranty covers manufacturing defects and workmanship under normal use. It does not cover damage caused by misuse, improper maintenance, unauthorized modifications, or normal wear and tear.

For specific warranty terms and conditions, or to initiate a warranty claim, please retain your proof of purchase and contact Aqualung customer service or an authorized Aqualung dealer.

Customer Support

If you have any questions, require technical assistance, or need to report an issue that cannot be resolved using the troubleshooting guide, please contact Aqualung customer support. You can typically find contact information on the official Aqualung website or through your authorized dealer.

When contacting support, please have your product model (i550) and serial number (if applicable) readily available to expedite the process.