DOCUMENT 1136
REV. G
Instruction Manual
Pro APF Series LED
ICAO TCL, IHP, & STP
9
NOTICE
The groove is designed to be wider than the o-ring. This provides room for the
displacement of the o-ring when compressed between the groove on the optical
housing and mating surface on the inner cover. Properly tightened screws are
important in obtaining a complete seal.
9.4 Lens Replacement
If a lens is broken, leaks, or is badly pitted or scarred, it must be replaced. It is highly recommended that
this task be performed in a clean shop environment. Lens replacement kits contain all necessary parts to
change a lens. Arctic kit replacement kits include replacement lenses for units with arctic kits. Refer to
section 10 to determine the appropriate replacement kit for your light unit.
Remove and secure
power to the light unit.
Separate the optical assembly from the light base by removing the two bolts.
There are two pry slots in the optical housing to help separate the optical assembly from the light base.
Disconnect the light unit lead(s) from the isolation transformer(s). Turn the optical assembly upside down and
remove the four screws holding the inner cover to the optical housing. Disconnect the power supply lead(s) from
the LED modules. Remove the two screws holding the LED module to the optical housing. If you are replacing
an arctic kit, remove the #6 tie-down screw which fastens the end of the arctic kit’s flexible circuit heater to the
optical housing. Remove the two lens retaining bracket screws from the light housing. Remove the lens-retaining
bracket and discard the lens-retaining gasket. Firmly push the lens/boot assembly from the outside of the light
housing; discard the old lens and boot. If you are replacing an arctic kit, discard the arctic kit assembly as an
electronic assembly. Thoroughly clean the lens opening with denatured alcohol and allow it to dry. Inspect the
lens opening for scratches or pits; a damaged lens opening surface will not seal properly. Place a new lens boot
over the replacement lens. Apply a thin coat of Dow Corning FS 1292 grease over the entire outside surface
of the lens boot. Align the lens/boot assembly in the lens opening and press it into place. Verify that the
lens boot is not pinched in the lens opening. Using a new lens retaining gasket, fasten the lens retaining
bracket, and heater tie-down screw on arctic kit versions, to the light housing. Torque the lens retaining
bracket mounting screws to 6.2-6.8 N-m (55-60 in-lb) and the heater tie-down screw, if applicable, to 0.9-
1.2 N-m (8-11 in-lb) . Re-install the LED module(s) per paragraph 9.2. Tighten the cap screws to 2.49-2.71 N-
m (22-24 in-lb). Connect the power supply leads to the LED assemblies. Inspect/replace the optical
housing’s o-ring per paragraph 9.3.
Assemble the inner cover onto the light housing. The screw hole
patterns in the inner cover and optical housing are offset to insure proper alignment. Torque the mounting
screws to 2.8-3.4 N-m (25-30 in-lb). Perform a pressure test per paragraph 9.6. Connect the light unit lead(s)
to the isolation transformer(s). Clean the mounting flange area of the light base. Place the optical assembly
into the light base. Torque bolts per section 8.4.
9.5 Feed-through Replacement
Refer to section 10 to determine the appropriate replacement kit for your light unit.
Remove and
secure power to the light unit.
Separate the optical assembly from the light base by removing the two
bolts. There are two pry slots in the optical housing to help separate the optical assembly from the light base.
Disconnect the light unit lead(s) from the isolation transformer(s). Disconnect the power supply leads from the
feed-thru terminals. Remove the feed-through by unscrewing the retaining collar. Clean the mounting surfaces
with denatured alcohol and allow to dry. Apply a thin coat of Dow Corning FS 1292 grease to the mounting
flange of a new feed-through. Apply a drop of Loctite 243 to the feed-through adapter threads. Screw the
feed-through retaining collar onto the adapter; refer to
for proper inner cover/feed-through orientation.
Torque the retaining collar to 2.8-3.4 N-m (25-30 in-lb). Reconnect the power supply leads to the feed-through
terminals. Inspect/replace the optical housing’s o-ring per section 9.3.
Assemble the inner cover onto the
light housing. The screw hole patterns in the inner cover and light housing are offset to insure proper
alignment. Torque the mounting screws to 2.8-3.4 N-m (25-30 in-lb). Perform a pressure test per paragraph
