Garrett Ace 250 Owners Manual: A Comprehensive Guide
This manual provides detailed instructions for operating your Garrett Ace 250, a popular metal detector, ensuring optimal performance and successful treasure hunting experiences.
The Garrett Ace 250 is a highly regarded metal detector, celebrated for its user-friendly design and reliable performance, making it ideal for beginners and hobbyists alike. Garrett, a company with over 50 years of experience in metal detection technology, has crafted a detector capable of locating coins, relics, jewelry, and more. Its crossover appeal, boosted by collaborations like the one with DEAG in 2006, demonstrates its broad market reach. This manual will guide you through every aspect of the Ace 250, from initial setup to advanced techniques, unlocking its full potential for exciting discoveries.
Unboxing and Component Identification
Upon opening your Garrett Ace 250 package, carefully inspect the contents. You should find the Ace 250 control housing, a three-piece stem assembly (upper, middle, and lower), a 6.5” x 8” PROformace™ concentric search coil, and coil cable connector. Also included are armrest components, and necessary hardware for assembly. Ensure all parts are present and undamaged. Familiarize yourself with each component before proceeding. Garrett manufactures these detectors in the USA, upholding quality standards. Refer to diagrams within this manual for visual identification of each part, ensuring a smooth assembly process.

Setting Up Your Ace 250
Proper setup is crucial for optimal performance. This section details installing batteries, assembling the detector, and adjusting the armrest and stem for comfortable use.
Installing Batteries
The Garrett Ace 250 requires four AA batteries to operate. Locate the battery compartment, typically on the control housing. Ensure correct polarity when inserting the batteries – positive (+) and negative (-) ends must align with the markings inside the compartment. Use only fresh, high-quality alkaline batteries for the best performance and longest runtime. Avoid mixing old and new batteries, or different battery types. A low battery indicator will appear on the LCD screen when replacement is needed, signaling it’s time to install a new set for continued treasure hunting success.
Assembling the Ace 250
Begin by attaching the lower stem section to the control housing, ensuring a secure twist-lock connection. Next, connect the upper stem section to the lower stem, again utilizing the twist-lock mechanism. Adjust the stem length for comfortable operation – a slight bend in your elbow when holding the detector is ideal. Finally, attach the search coil connecting cable to the control housing. Ensure the connector is firmly seated. Double-check all connections before use to prevent interruptions during your search. Proper assembly guarantees stable and efficient metal detecting.
Adjusting the Armrest and Stem
For optimal comfort, adjust the armrest by loosening the knob and positioning it to comfortably support your forearm. Tighten the knob securely once adjusted. The stem length is crucial for balanced operation; loosen the stem clamps and extend or retract the stem sections until a slight bend remains in your elbow when holding the detector. Retighten the clamps firmly. Proper adjustment minimizes fatigue during extended use and maximizes control, allowing for precise sweeping motions and improved detection accuracy. Regularly check tightness during use.

Understanding the Control Panel
The Ace 250’s control panel features intuitive buttons for power, sensitivity, discrimination, frequency, and volume, enabling customized search settings for various terrains.
Power Button and Sensitivity Adjustment
The power button initiates the Ace 250, activating its detection capabilities. Sensitivity controls the detector’s depth and responsiveness to smaller targets; higher settings detect deeper but may increase interference. Begin with a lower sensitivity setting in highly mineralized ground to minimize false signals. Gradually increase sensitivity until a stable operation is achieved, balancing depth with signal clarity. Proper sensitivity adjustment is crucial for effective treasure hunting, maximizing detection while minimizing unwanted responses from ground minerals or electrical interference. Experiment to find the optimal setting for your specific hunting location.
Discrimination Control
The discrimination control on the Garrett Ace 250 allows you to selectively filter out unwanted metallic targets. By adjusting the discrimination level, you can choose to ignore signals from iron, aluminum, or other junk metals, focusing on potentially valuable finds like coins and jewelry. Experiment with different discrimination settings based on your hunting location and desired targets. Higher discrimination levels reject more targets, but may also eliminate desirable items. Careful adjustment is key to maximizing recovery rates of valuable finds while minimizing digging unnecessary holes.
Frequency Adjustment
The Garrett Ace 250 features frequency adjustment to minimize interference from external sources like electrical fields or other metal detectors. While not a primary tuning function for typical users, adjusting the frequency can improve performance in challenging environments. If you experience erratic signals or “phantom” hits, subtly altering the frequency may reduce the impact of electromagnetic interference. This feature is particularly useful when detecting in areas with high electrical activity or near other operating devices. Experiment cautiously to find the clearest signal.
Volume Control and Headphone Jack
The Ace 250’s volume control allows you to adjust the audio output to suit your hearing and the surrounding environment. Increasing the volume enhances target signal clarity, but be mindful of excessive levels that could mask subtle indications; A standard ¼-inch headphone jack is conveniently located near the volume control, enabling private listening and improved audio definition. Using headphones significantly reduces external noise interference, allowing for more precise target identification and a more enjoyable detecting experience. Ensure headphones are securely connected for optimal performance.

Operating Modes and Search Settings
The Ace 250 offers versatile modes – All Metal, Discrimination, Jewelry, and Custom – allowing users to tailor search parameters for diverse detecting scenarios.
All Metal Mode
All Metal mode on the Garrett Ace 250 is your foundational search setting, detecting all metallic objects regardless of their composition. This mode maximizes detection depth and is ideal for locating deeply buried targets, or when you’re unsure of the potential targets in an area. It doesn’t discriminate against any metal type, meaning it will respond to iron, aluminum, gold, silver, and everything in between.
However, be prepared for more false signals from unwanted trash like iron nails and foil. Experienced users often start in All Metal mode to locate potential target areas, then switch to Discrimination mode to filter out unwanted metals and focus on more valuable finds. It’s a crucial starting point for serious treasure hunting.
Discrimination Mode
Discrimination mode on the Garrett Ace 250 allows you to selectively ignore certain metal types, reducing unwanted signals from trash like iron and aluminum. Using the Discrimination control, you can ‘notch out’ specific target IDs, effectively filtering them from detection. This significantly speeds up your recovery time and focuses your efforts on potentially valuable targets like gold, silver, and copper.
However, be cautious when increasing discrimination levels, as you might also exclude desirable targets with similar conductivity to trash metals. Experimentation and understanding the target ID chart are key to optimizing discrimination settings for your specific hunting location.
Jewelry Mode
The Jewelry Mode on the Garrett Ace 250 is a pre-programmed setting designed to enhance the detection of gold, silver, and platinum jewelry. This mode automatically adjusts the detector’s sensitivity and discrimination to prioritize signals from these valuable metals. It effectively filters out most iron and other common trash targets, making it ideal for searching beaches, parks, and other areas where jewelry is commonly lost.
While highly effective, remember that Jewelry Mode isn’t foolproof; it may still detect other metallic objects. Careful digging and target identification are always recommended.
Custom Mode
The Garrett Ace 250’s Custom Mode allows experienced users to tailor the detector’s settings to specific hunting conditions and target preferences. This mode provides full control over sensitivity, discrimination, frequency, and iron volume. Experimenting with these settings enables you to optimize performance for challenging environments or to target specific types of metal.
Saving your preferred settings as a custom profile ensures quick access to your ideal configuration. Remember to document your changes for future reference and to understand how each adjustment impacts detection depth and accuracy.

Advanced Features and Techniques
Explore ground balance, pinpoint mode, and frequency adjustment to enhance your Garrett Ace 250’s performance, overcoming interference and maximizing target recovery.
Ground Balance Adjustment
Ground balancing is crucial for optimal performance with the Garrett Ace 250, especially in mineralized soils. This process calibrates the detector to ignore ground signals, allowing it to detect deeper targets. Begin by selecting a clear area and slowly adjust the ground balance setting while observing the detector’s response.
A stable threshold tone indicates proper balance. If the tone fluctuates, continue adjusting until stability is achieved. Automatic ground balance is available, but manual adjustment often yields better results in challenging conditions. Proper ground balance significantly improves detection depth and reduces false signals caused by ground mineralization, enhancing your treasure hunting success.
Pinpoint Mode
The Garrett Ace 250’s pinpoint mode helps precisely locate a detected target within the dug hole, saving time and minimizing damage. Activate pinpoint mode by pressing the pinpoint button on the control panel. The detector will emit a series of tones, indicating the target’s proximity.
Slowly sweep the coil back and forth over the area; the tones will become louder and more consistent as you center the coil over the target. This narrows down the exact location for careful excavation. Use pinpoint mode after identifying a target with another mode for best results.
Frequency Adjustment for Interference
The Garrett Ace 250 allows for frequency adjustment to minimize interference from external sources like electrical lines or other metal detectors. If you experience erratic signals or noise, try slightly adjusting the frequency; This feature isn’t a traditional frequency selection, but a subtle shift to find a clearer channel.
Experiment with small adjustments while searching; listen for a reduction in interference. While not always necessary, frequency adjustment can significantly improve performance in areas with high electromagnetic interference, leading to more accurate target identification.

Interpreting Target Signals
Understanding the Ace 250’s audio tones and visual target ID is crucial for successful metal detecting, helping you identify potential treasures efficiently.
Understanding Audio Tones
The Garrett Ace 250 utilizes distinct audio tones to help differentiate between various metal types. A low-tone signal generally indicates iron or junk metal, while a higher-pitched tone suggests more valuable targets like silver or copper. Learning to recognize these subtle differences is key to efficient treasure hunting. The detector’s audio response also varies based on target depth and size; stronger signals typically mean shallower, larger objects. Practice identifying tones in different environments to refine your skills and minimize digging unnecessary holes. Familiarize yourself with the tone variations for optimal results.
Visual Target ID Interpretation
The Ace 250’s LCD screen displays a Target ID number, ranging from 0 to 99, offering a visual indication of the detected metal. Lower numbers typically represent iron, while higher numbers suggest more conductive targets like silver or gold. However, this is an estimate, and ground conditions can influence readings. Utilize the Target ID alongside audio tones for accurate identification. Remember that overlapping numbers indicate potential mixed metals. Practice correlating the visual ID with dug targets to learn the specific responses in your hunting locations, improving your interpretation skills over time;
Identifying Different Metal Types
The Garrett Ace 250 helps differentiate metals through a combination of Target ID numbers and audio tones. Iron typically produces a low-tone signal and a low Target ID. Silver generally yields a higher-pitched tone and a higher ID number. Copper and brass fall in between, offering mid-range signals. Gold can be tricky, often presenting a faint signal, so careful digging is crucial. Remember, mineralization and depth affect signals. Practice identifying known targets to refine your ability to distinguish between valuable finds and unwanted trash, maximizing your treasure hunting success.

Maintenance and Care
Regular cleaning, proper battery replacement, and careful storage will extend the life of your Garrett Ace 250, ensuring years of reliable metal detecting adventures.
Cleaning Your Ace 250
To maintain your Garrett Ace 250’s performance and longevity, regular cleaning is essential. After each use, especially in sandy or mineralized soil, wipe down the coil, stem, and control housing with a damp cloth. Avoid using harsh chemicals or abrasive cleaners, as these can damage the detector’s components. For stubborn dirt, a mild soap solution can be used, followed by a thorough rinse with clean water.
Ensure all connections are dry before storing. Pay particular attention to the battery compartment, preventing corrosion. Proper cleaning safeguards against environmental damage and ensures accurate readings during future hunts.
Battery Replacement
The Garrett Ace 250 requires four AA batteries for operation. When the low battery indicator appears on the control panel, promptly replace all batteries simultaneously for consistent performance. Open the battery compartment located on the control housing. Remove the old batteries, noting the correct polarity (+ and -) as indicated inside the compartment.
Insert new AA batteries, ensuring proper alignment. Close the battery compartment securely. Using rechargeable batteries is acceptable, but may provide slightly less operating time. Always dispose of used batteries responsibly, following local regulations.
Storage Guidelines
Proper storage extends the life of your Garrett Ace 250. Before long-term storage, thoroughly clean the detector, removing any dirt or debris. Remove the batteries to prevent corrosion and potential damage. Disassemble the Ace 250, separating the search coil from the control housing, and store them independently.
Keep the detector in a cool, dry place, away from direct sunlight and extreme temperatures. Avoid storing it in damp environments like garages or sheds. A protective bag or case is recommended. Periodically check the stored components for any signs of deterioration.

Troubleshooting Common Issues
This section addresses typical problems with the Garrett Ace 250, like no power, erratic signals, or false readings, offering solutions for a smooth experience.
No Power
If your Garrett Ace 250 fails to power on, begin by verifying the batteries are correctly installed with the proper polarity. Ensure the battery compartment is clean and free of corrosion, as this can interrupt the electrical connection. Try replacing the batteries with a fresh set of alkaline batteries; rechargeable batteries may not provide sufficient voltage.
Confirm the power switch is fully engaged. A loose connection within the battery compartment or a faulty power switch could also be the cause. If the issue persists after these checks, consult a qualified technician for further assistance, as internal component failure may be present.
Erratic Signals
Experiencing erratic signals with your Garrett Ace 250 can be frustrating. This often stems from external electromagnetic interference (EMI) from sources like power lines, cell towers, or other metal detectors. Try relocating to a different search area, further away from potential interference sources. Adjusting the frequency setting can also help minimize EMI.
Ground mineralization can also cause unstable readings; attempt ground balance adjustment. Ensure proper coil connection and check for damage to the coil cable; If signals remain erratic, reduce sensitivity levels to stabilize the detector’s response.
False Signals
The Garrett Ace 250 may occasionally produce false signals, often triggered by small iron objects or heavily mineralized ground. Utilize the discrimination feature to filter out unwanted targets, specifically iron and low-conductance metals. Ensure proper ground balance is set for your current location, as mineralization significantly impacts signal accuracy.
Check for nearby metallic debris, like bottle caps or aluminum foil, which can mimic genuine targets. Lowering the sensitivity can also reduce the number of false readings, though it may decrease detection depth.

Garrett Metal Detector Product Line Overview
Garrett offers a diverse range of metal detectors, from beginner models like the Ace 250 to advanced units for professionals, catering to various needs and budgets.
Comparison of Garrett Metal Detectors
Garrett’s lineup spans diverse needs. The Ace 250, ideal for beginners, offers simplicity and affordability. Stepping up, the Ace 300 and 400 provide enhanced features like digital target ID and increased frequency options. For serious enthusiasts, the AT Pro delivers all-terrain capability and advanced ground balance. The AT Gold is specialized for gold prospecting, while the GTX 5000 boasts pulse induction technology for deep detection in highly mineralized soils.
Higher-end models, such as the Sea Hunter Mark II, are designed for underwater treasure hunting. Each detector balances price, performance, and features, allowing users to select the best tool for their specific detecting goals.
Garrett’s History and Manufacturing
For over 50 years, Garrett has been a leading innovator in metal detection technology. Founded on a commitment to quality, the company initially focused on security applications before expanding into hobbyist and industrial markets. Garrett Metal Detectors are proudly designed and manufactured in the USA, ensuring rigorous quality control.
Their success surged in Germany through partnerships with DEAG, emphasizing the event-driven nature of classical concerts. Garrett continues to develop cutting-edge solutions for sport, security, and even mine detection, consistently pushing the boundaries of detection technology.
Purchasing Genuine Garrett Products
To guarantee authenticity and quality, always source your Garrett Ace 250 and accessories from factory-authorized distributors for reliable performance.
Authorized Distributors
Ensuring you purchase genuine Garrett products is crucial for performance and warranty validity. Authorized distributors offer authentic Ace 250 metal detectors and related accessories, safeguarding against counterfeits. These distributors are carefully vetted by Garrett to provide expert advice, reliable service, and genuine parts.
Locating an authorized dealer is simple; visit the official Garrett website and utilize their dealer locator tool. This tool allows you to search by location, ensuring convenient access to trusted retailers. Purchasing from authorized sources guarantees you receive a fully supported product with access to the latest updates and assistance.

Garrett Motion Inc. and Turbo Technologies
While distinct from metal detection, Garrett Motion Inc. showcases the broader engineering expertise of the Garrett name, focusing on turbo and hybrid technologies.
Garrett’s Role in Turbo and Hybrid Applications
Garrett’s Role in Turbo and Hybrid Applications
Though renowned for metal detectors, Garrett’s legacy extends significantly into the automotive industry through Garrett Motion Inc. Formerly Honeywell Transportation Systems, they specialize in engineering, developing, and manufacturing turbochargers. These technologies boost engine efficiency and reduce emissions in both traditional combustion engines and increasingly, hybrid and fully electrified vehicles.
Garrett delivers differentiated solutions, enhancing horsepower and performance across a wide range of applications. This demonstrates a core competency in precision engineering and advanced materials science, a foundation also utilized in crafting reliable and sensitive metal detection equipment like the Ace 250.
