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Dental Delivery Unit Operation Manual
REV-A
Page 38 of 45
Replace the faulty PCB
Replace the faulty controlling
keyboard
9
All the control is
invalid
The power is not connected
well
The power fuse is burn out
Transformer in junction box
is damaged
Power switch is damaged
Replace the power plug or
socket
Find the exact reason and
replace the fuse
Replace the transformer
Replace the power switch
10
No water from dental
unit
Water filter is jammed
Water tube is dented
Clean the filter element
Restore the water tube
11
Water comes out with
air
The handpiece connector is
not tighten
Filter reducing valve is full
of water
Tighten the handpiece
connector
Release the water of filter
reducing valve
12
Operation light
doesn’t work
The bulb is damaged
Loose contact of operation
light connecting line
Loose contact of operation
light switch
Loose contact of outgoing
line of transformer in
junction box
Replace the faulty bulb
Find the loose contacting
position
Replace the operation light
switch
Reconnect the outgoing line or
replace the transformer
13
Chair position can’t
be controlled but
with normal sound,
and other keys can
work normally
Loose contact of relay
contact point or damage of
coil
Damage of motor or open
circuit of connecting line
Clean the relay contact point or
replace a the relay
Find out and reconnect the
open circuit position or replace
the motor
14
X-ray viewer doesn’t
work
The modulator tube is
damaged
Loose contact of
connecting line
Replace the modulator tube
Repair the loose connecting
position of the connecting line