5
Pump
draws
excessively
high
current
Motor
is
overloaded
Turn
off
pump
Remove
all
pressure
and
vacuum
conditions
Restart
and
test
at
atmospheric
pressure
Power
input
is
incorrect
Check
motor
wiring
i.e.
115
V
vs
230
V
wiring
Check
power
source
o
Pumps
are
only
rated
for
±10%
voltage
on
name
plate
Low
or
zero
flow
Connection
or
sample
line
blocked
Remove
blockage
Liquid
or
foreign
debris
has
collected
in
the
head
Clean
out
the
head,
see
section
“Servicing”
Place
pump
outlet
facing
downward
Diaphragms,
valves,
or
gasket
are
worn
See
section
“Servicing”
Pump
is
rattling
or
knocking
Connecting
rod
bolt
or
diaphragm
plate
screw
are
under
torqued
See
section
“Servicing”
for
torquing
specifications
Connecting
rod
cap
is
too
close
to
one
side
of
housing
Using
a
screw
driver
lightly
pry
the
cap
away
from
the
side
of
the
housing
and
center.
A
centering
tool
is
available
for
purchase
at
ADI.
Servicing
Listed
below
are
the
two
predominant
types
of
maintenance
typical
for
Dia
‐
Vac®
Pumps,
the
servicing
of
the
consumable
parts
(diaphragm,
valve
discs,
gasket,
and
Teflon®
washer),
and
the
servicing
of
the
connecting
rod.
For
video
instructions
on
servicing
the
head
and
diaphragm
visit
http://www.airdimensions.com/service/videos/
.
Disassembly
of
Head
Section
and
Diaphragm
Remove
head
assembly
by
unscrewing
the
four
head
bolts.
A
flat
‐
bladed
screw
driver
may
be
needed
to
gently
pry
the
head
free
of
the
service
diaphragm.
**If
the
heads
have
Teflon®
coating
use
caution
not
to
scratch
the
surface.
The
valve
body
can
then
be
removed
by
unscrewing
the
two
smaller
screws
(also
accessible
on
the
top
of
the
head
section).
This
part
may
be
freed
by
gently
tapping
on
these
two
screws
after
they
have
been
loosened
about
three
or
four
turns.
When
the
valve
body
is
removed,
check
all
internal
surfaces
for
any
accumulation
of
dirt.
The
two
valve
discs
can
be
wiped
clean
and
replaced
as
long
as
they
appear
unaffected
by
usage.
The
valve
gasket
can
be
easily
removed
and
should
be
inspected.
As
a
matter
of
good
