Hilti DD 150-U, Manual

Page: 52 / 534

44 English 434949
*434949*
Malfunction Possible cause Action to be taken
The diamond core bit doesn’t
rotate. The diamond core bit has become
jammed in the hole.
▶
Guide the diamond core drilling
machine in a straight line.
▶ Use an open-end wrench to
release the core bit: Disconnect
the supply cord plug from
the power outlet. Grip the
diamond core bit with a suitable
open-end wrench close to the
connection end and release the
diamond core bit by rotating it.
▶ If using a drill stand: Turn the
hand wheel and try to release
the diamond core bit by moving
the carriage up and down.
The rate of drilling progress
decreases. Maximum drilling depth has been
reached. ▶ Remove the core and use a core
bit extension.
The core is stuck in the core bit. ▶ Remove the core.
Wrong core bit specification for the
base material.
▶
Select a more suitable diamond
core bit specification.
High steel content (indicated by
clear water containing metal cut-
tings). ▶ Select a more suitable diamond
core bit specification.
The diamond core bit is defective. ▶ Check the diamond core bit
for damage and replace it if
necessary.
Wrong gear selected. ▶ Select the right gear.
Contact pressure is too low. ▶ Increase the contact pressure.
The machine has too little power. ▶ Select the next lower gear.
The diamond core bit is polished. ▶ Sharpen the diamond core bit
by drilling into a sharpening
plate.
The water flow rate is too high. ▶ Reduce the water flow rate
by adjusting the water flow
regulator.
The water flow rate is too low. ▶ Check the water supply to the
diamond core bit respectively
increase the water flow rate by
adjusting the water regulator.
The carriage lock is engaged. ▶ Release the carriage locking
mechanism.
Dust is hindering drilling progress. ▶ Use a suitable dust removal
system.
The hand wheel can be
turned without resistance. The shear pin is broken.
▶
Replace the shear pin.
The diamond core bit cannot
be fitted into the chuck. The core bit connection end or
chuck is dirty or damaged. ▶ Clean and grease the connec-
tion end and/or the chuck or
replace these parts.
Water escapes at the water
swivel or gear housing. The water pressure is too high. ▶ Reduce the water pressure.
Water escapes at the chuck
during operation. The diamond core bit isn’t securely
tightened in the chuck.
▶
Tighten the diamond core bit
securely.
▶ Remove the diamond core bit.
Rotate the diamond core bit
approx. 90° about its own axis.
Refit the diamond core bit.
Printed: 09.08.2019 | Doc-Nr: PUB / 5069546 / 000 / 09