Pumps & Conveying System Components Chapter 6: Troubleshooting 44
Possible Remedy
Vacuum line problem.
Disconnect the vacuum line at
the first vacuum hopper and
block it off. The vacuum here
should equal the vacuum at
the blower. Allow a few
seconds for vacuum to build.
If the vacuum here is low,
disconnect the piping halfway
to the first vacuum hopper and
check the vacuum there. If
proper vacuum exists, the
problem is upstream. If not,
work backward to isolate the
vacuum loss.
Pump package blower
problem. Use a cfm/cfh
monitoring device to ensure
that blower cfm/cfh is to the
manufacturer’s specifications.
Consult Service Engineer if
problem persists.
(Cont’d.)
• Tighten loose pipe
couplers; replace worn
gaskets as needed.
• Replace any damaged
piping found.
Leaks in vacuum lines
between valves.
Check for leaks as described
in previous steps.
Vacuum leak(s) in vacuum
hoppers.
• Replace or re-install worn or
misaligned gaskets.
• Hopper discharge flapper
not sealing under vacuum.
1) Replace worn or missing
gasket.
2) Clean fouled flapper.
3) Check counterweight for
proper operation. Repair
or adjust as needed.
• Internal check valves
missing or damaged. On
single line Y systems,
internal check valves must
be installed in the vacuum
hoppers to seal all hoppers
not being conveyed to. If the
check valves are present and
undamaged, they may be
pushed too far onto the tube
stub to permit a proper seal.
Also, if the hopper is over-
filled, the check valve may
not seal properly.
Vacuum conveying rate is
declining due to a vacuum loss
in the system.
(Cont’d.)
Vacuum leaks in material
lines.
Check for leaks as described in
previous steps.
