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GTEMP10-TH NMEA
2000® Thru-hull
Temperature Sensor
Installation Instructions
Important Safety Information
WARNING
See the Important Safety and Product Information guide in the
chartplotter or fishfinder product box for product warnings and
other important information.
CAUTION
Failure to install and maintain this equipment in accordance with
these instructions could result in damage or injury.
Always wear safety goggles, ear protection, and a dust mask
when drilling, cutting, or sanding.
NOTICE
When drilling or cutting, always check what is on the opposite
side of the surface.
This equipment should be installed by a qualified marine
installer.
• If you have a question about the location of the thru-hull
sensor, you should contact your vessel builder or other
owners of similar vessels for advice.
Tools Needed
• Drill
• 25 mm (1 in.) hole saw
• 34 to 37 mm (11/3 to 11/2 in.) hole saw (cored-fiberglass hull
installations)
• Marine sealant
• Silicone grease
• Metal file (metal-hull installations)
• Fiberglass cloth and resin (option for sealing a coredfiberglass hull)
• 25 mm (1 in.) cylinder, wax, tape, and casting epoxy (option
for sealing a cored-fiberglass hull)
Installing the Thru-hull Temperature Sensor
Before you can mount the sensor in a cored-fiberglass hull, you
must prepare the hull (Preparing a Cored-Fiberglass Hull,
page 1).
From outside the boat, use a 25 mm (1 in.) hole saw to cut
1
through the hull at the mounting location.
Clean the area using a mild detergent or weak solvent, such
2
as isopropyl alcohol, to remove any dust and dirt.
From outside the boat, thread the cable through the hull, and
3
gently slide the threaded housing into place to check the fit.
NOTE: The housing should slip into place easily, with the
flange contacting the hull.
Remove the housing.
4
Apply marine sealant to the flange, reinsert the housing into
5
the drilled hole, and tighten the nut.
After the marine sealant has cured, remove the nut and apply
6
sealant to the inner side of the hull and the housing.
Tighten the nut by hand.
7
Allow the sealant to cure.
8
Preparing a Cored-Fiberglass Hull
To obtain the best performance and to avoid damage to your
boat, you must install the Garmin® device according to these
instructions.
Read all installation instructions before proceeding with the
installation. If you experience difficulty during the installation,
contact Garmin Product Support.
Registering Your Device
Help us better support you by completing our online registration
today.
• Go to my.garmin.com.
• Keep the original sales receipt, or a photocopy, in a safe
place.
Contacting Garmin Product Support
• Go to www.garmin.com/support for in-country support
information.
• In the USA, call 913-397-8200 or 1-800-800-1020.
• In the UK, call 0808 238 0000.
• In Europe, call +44 (0) 870 850 1241.
Mounting Considerations
• The sensor should not be mounted in a location where it
might be jarred when launching, hauling, or storing.
• The sensor must be mounted where the hull thickness is from
0 to 57 mm (from 0 to 21/4 in.).
NOTICE
If the core of a cored-fiberglass hull is not sealed properly, water
may seep into the core and severely damage the boat.
Fiberglass or casting epoxy (not included)
À
Cylinder spacer (not included)
Á
Inner fiberglass skin
Â
Core
Ã
Outer fiberglass skin
Ä
Drill the hole through the hull.
1
Seal the core inside the hull using either fiberglass (Sealing
2
the Core with Fiberglass, page 2) or casting epoxy
(Sealing the Core with Casting Epoxy, page 2).
Drilling a Hole in a Cored-Fiberglass Hull
From inside the boat, drill a 3 mm (1/8 in.) pilot hole
1
completely through the hull.
April 2016
Printed in Taiwan 190-02057-02_0A
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Examine the pilot hole on the outside of the boat, and select
2
an option:
• If the pilot hole is not in the correct location, seal the hole
with epoxy and repeat step 1.
• If the pilot hole is in the correct location, use a 25 mm (1
in.) hole saw to cut a hole from the outside of the boat
through the outer fiberglass skin only. Do not cut
completely through the hull.
On the inside of the boat, at the pilot hole location, use a hole
3
saw to cut a hole 9 to 12 mm (3/8 to 1/2 in.) larger than the
hole you cut in the outside of the boat in step 2.
Cut through the inner fiberglass skin and most of the core,
without cutting the outer skin.
NOTE: When cutting the inner fiberglass skin and core, be
careful to not cut the outer fiberglass skin, or you will not be
able to correctly seal the hull.
Remove the inner fiberglass skin and core you cut in step 3.
4
You should be able to see the inside of the outer fiberglass
skin.
Sand the inside of the hole and the areas immediately around
5
both the inside and outside fiberglass skin.
Clean the area using a mild detergent or weak solvent, such
6
as isopropyl alcohol, to remove any dust and dirt.
Sealing the Core with Fiberglass
From inside the boat, coat a layer of fiberglass cloth with
1
fiberglass resin and place it inside the hole to seal the core.
Add layers of fiberglass cloth and resin until the hole is
2
25 mm (1 in.) in diameter.
After the fiberglass has hardened, sand and clean inside and
3
around the hole.
The cored-fiberglass hull is now prepared, and you can
complete the sensor installation.
Sealing the Core with Casting Epoxy
Before you can seal the core with casting epoxy, you must
create a cylinder with a diameter of 25 mm (1 in.) to act as a
spacer as the epoxy sets.
Coat a 25 mm (1 in.) cylinder with wax.
1
From outside the boat, insert the cylinder into the hole, and
2
tape it in place on the outer surface.
Fill the space between the cylinder and the core with casting
3
epoxy.
After the epoxy has hardened, remove the cylinder, then
4
sand and clean inside and around the hole.
The cored-fiberglass hull is prepared, and you can complete
the sensor installation.
NMEA 2000 Connection
NMEA 2000 thru-hull temperature sensor
À
NMEA 2000 device
Á
Drop cable
Â
T-connector
Ã
Existing NMEA 2000 network
Ä
Thru-hull Temperature Sensor Configuration
For instructions on finding the NMEA 2000 device list, see your
compatible Garmin chartplotter or instrument manual.
Assigning a NMEA 2000 Temperature Source
From the NMEA 2000 device list, select the NMEA 2000 thru-
1
hull device.
Select a device.
2
If necessary, select Review or Config..
3
Select Temp. Source.
4
Select the location of the temperature sensor.
5
Configuring the Temperature Offset
When the temperature data displayed on the gauge connected
to your NMEA 2000 device is not the same as temperature data
displayed on other devices, you can configure the temperature
offset to compensate for the temperature reading from the
sensor connected to the gauge.
From the NMEA 2000 device list, select the NMEA 2000 thru-
1
hull device.
Select a device.
2
If necessary, select Review or Config..
3
Select Temp. Offset.
4
Enter a value, in degrees.
5
NOTE: Enter the temperature offset value as a positive
number when the sensor measures the water temperature as
being colder than it actually is. Enter the temperature offset
value as negative when the sensor measures the water
temperature as being warmer than it actually is.
Select Done.
6
Troubleshooting the Sensor Number
When multiple adapters are assigned to a NMEA 2000
temperature source, each adapter is assigned a unique sensor
number automatically. If an invalid NMEA 2000 temperature
configuration error message appears, you must assign a unique
sensor number to each adapter manually.
From the NMEA 2000 device list, select the NMEA 2000 thru-
1
hull device.
Select a device.
2
If necessary, select Review or Config..
3
Select Sensor Number.
4
Select a sensor number.
5
Select OK.
6
Configuring the Temperature Source when the
Location Is Not Displayed
From the NMEA 2000 device list, select the NMEA 2000 thru-
1
hull device.
Select a device.
2
If necessary, select Review or Config..
3
Select Generic Config..
4
Enter TEMPSOURCE=.
5
Enter a temperature source value based on the location of
6
the temperature data source, followed by Done.
For example, enter TEMPSOURCE=6Done for a temperature
data source placed in a bait well.
2