GT15M-THF 0° through-hull CHIRP mid-frequency fishfinder

Yes, the Garmin GT15M-THF transducer is made of stainless steel and is compatible with a wide range of hull materials, including fiberglass, wood, composites, aluminum, and steel.

For installations on metal hulls (aluminum or steel), it is imperative to use the included galvanic isolation components to prevent corrosion and ensure watertight integrity.

The "0 degree" designation for this transducer indicates it is specifically designed and optimized for deadrise angles ranging from 0 to 5 degrees. For optimal sonar performance, it is critical that the transducer angle matches as closely as possible the deadrise angle at the chosen installation location on your boat.

Yes, to achieve the best possible performance and avoid potential damage to the equipment or your boat, installation by a qualified marine technician is strongly recommended. It is also important to always wear safety glasses, hearing protection, and a dust mask when drilling, cutting, or sanding.

Required hole diameters vary depending on your boat hull material:

For a fiberglass hull (solid or cored), a 73 mm (2 7/8 in) hole saw is required. For a metal hull (aluminum or steel), a 75 mm (3 in) hole saw is required.

For installations on aluminum or steel hulls, it is imperative to use the galvanic isolation components included with the transducer. Omitting these components during installation would create galvanic corrosion that could lead to water ingress around the transducer and damage your boat.

Yes, for optimal performance, the transducer must be installed in an area of clean, non-turbulent water. Key points:

Avoid installing it behind strakes, frames, fittings, water intake or discharge openings, or anything that could create air bubbles. It must not be installed in the propeller wash path, as this could cause cavitation. On outboard or sterndrive-powered boats, it is typically mounted forward and near the engine(s). On inboard-powered boats, it must be mounted forward, away from the propeller and the engine shaft. The arrow on the top of the transducer must align with the boat’s keel so that the internal angle matches the keel angle.

Yes, you must update the software on your Garmin chartplotter when installing this transducer. This update ensures compatibility and optimal operation between the transducer and your Garmin device.

To avoid permanently damaging the transducer surface, follow these recommendations:

Never use solvents such as white spirit, acetone, methyl ethyl ketone (MEK), or similar products.Do not use an electric sander or pressure washer to clean the transducer.A mild detergent or rubbing alcohol can be used for cleaning.

The Garmin GT15M-THF transducer is made of stainless steel. This material ensures robustness and compatibility with various hull types, including fiberglass, wood, composites, aluminum, and steel.

The GT15M-THF transducer is compatible with fiberglass, wood, composite, aluminum, and steel hulls. Its stainless steel construction makes it particularly well-suited for metal hulls, unlike other brass models.

The Garmin GT15M-THF transducer is specifically designed for deadrise angles ranging from 0 to 5 degrees. It is critical to verify your boat’s deadrise angle at the chosen installation location to ensure optimal sonar performance.

Hole diameters vary depending on your hull material:

For fiberglass hulls (solid or sandwich): a 73 mm (2 7/8 in) hole is required. For metal hulls (aluminum or steel): a 75 mm (3 in) hole is required.

Yes, using the included galvanic isolation components is mandatory when installing the GT15M-THF transducer on an aluminum or steel hull. Failure to install them could result in galvanic corrosion and potential water ingress around the transducer.

For optimal performance, the depth sounder must be installed in an area of clean, non-turbulent water. Here are some general guidelines:

Outboard and sterndrive boats: Ahead of and near the engine(s).Inboard boats: Ahead of and away from the propeller and propeller shaft.Long-keeled boats: At a slight angle pointing forward, parallel to the centerline.Fine-keeled boats: 25 to 75 cm ahead of the keel and no more than 10 cm to the side of the centerline.Displacement-hull boats: Approximately one-third back from the waterline length from the bow, and 150 to 300 mm to the side of the centerline.The depth sounder must not be mounted behind strakes, frames, fittings, water intakes or discharges, or anything else that could create air bubbles or make the water turbulent.

The transducer must always be used when submerged. Operating it in open air can cause damage due to overheating. For cleaning, never use solvents such as white spirit, acetone, MEK (Methyl Ethyl Ketone), or similar products, as they can permanently damage the transducer surface. Do not use an electric sander or high-pressure cleaner to clean the transducer. Do not pull or lift the transducer by its cable to avoid damaging it.

To achieve optimal performance and avoid potential damage to the device or your sailboat, installation by a qualified marine technician is recommended.

For installing the transducer, you will need the following tools:

A drill and a 3 mm (1/8 in) drill bitA wrench suitable for nuts up to 75 mmMarine sealant (flexible, quick-curing type, for below the waterline)Mild household detergent or rubbing alcoholSandpaperMasking tapeWaterproof electrical tapeA 73 mm (2 7/8 in) hole saw for fiberglass hulls or a 75 mm (3 in) hole saw for metal hulls.Optionally, grommets and water-based antifouling paint may be required.

Yes, the GT15M-THF transducer is made of stainless steel and is specifically designed for installation in aluminum or steel hulls, as well as fiberglass, wood, or composite hulls. It includes galvanic isolation components to prevent corrosion in metal environments.

Yes, cutting or splicing the depth sounder cable, unless required for connection to a specific black box sonar unit, may void your warranty. It is recommended not to modify the cable.

During installation, it is crucial to rotate the transducer from inside the hull until the arrow on top of the transducer points toward the keel of the boat. This alignment is essential for the internal angle of the transducer to match the keel angle of the boat, ensuring optimal performance.