Hilti DD AF-CA H Mode D'emploi page 17

Malfunction
Diamond core bit jams
The auto-feed unit cannot be
installed.
The hand wheel cannot be
rotated.
The water flow rate is too low. Strainer of the auto-feed unit is
The auto-feed unit motor runs
but the carriage does not
move.
Cut Assist mode cannot be
activated.
The drilling operation slows or
stops.
*2299965*
Possible cause
The diamond core bit has become
jammed in the base material.
Square drive does not fit, or is not
turned to a position at which it can
slot into the adapter.
The flange on the carriage of the
drill stand or on the auto-feed unit
is dirty or worn.
The threaded bushing for the se-
curing screw is blocked.
The carriage lock is engaged.
The carriage is obstructed.
clogged.
Water valve of the auto-feed unit is
faulty or blocked.
The auto-feed unit is installed in-
correctly.
Auto-feed unit has no AC supply.
An emergency stop was triggered.
The diamond core bit is defective
(segments polished or destroyed).
The plug connector is faulty or the
cable is defective.
The diamond core bit is stuck.
Faulty or inadequate cooling.
2299965
Action to be taken
▶ Turn the hand wheel and try to
release the diamond core bit
by moving the carriage up and
down.
▶ Turn the auto-feed unit until the
square shaft and the square-
shaft socket are in alignment.
▶ Clean the flange and check the
flange for excessive wear.
▶ Replace excessively worn
components.
▶ Clean the threaded bushing.
▶ Try to turn the auto-feed unit to
match up the flanges.
▶ Check the threaded bushings
and the threaded studs.
▶ Make sure that the carriage is
free to move.
▶ Clean the strainer in the water
inlet.
▶ Connect the water supply
directly to the diamond core
drilling machine and check
whether the water valve on the
diamond core drilling machine
is working.
▶ Check whether the valve on
the auto-feed unit is blocked or
faulty.
▶ Check that the water supply is
installed correctly.
▶ Check the mechanical connec-
tion between the auto-feed unit
and the carriage.
▶ Check the electricity supply.
▶ Cancel the emergency stop by
pulling up the EMERGENCY
STOP switch. → page 5.
▶ If the problem persists, consult
Hilti Service.
▶ Sharpen the diamond core bit
or replace it.
▶ Check the connection between
the auto-feed unit and the
diamond core drilling machine.
▶ Disconnect the diamond core
drilling machine from the electric
supply.
▶ Release the diamond core bit.
▶ Check the water supply and
cooling circuit.
English 13