Nordson 25B - 2. Troubleshooting Charts

Troubleshooting
6-2
E 1999 Nordson Corporation
All rights reserved
104 330H
Issued 8/99
Manual 1-8
Problem Possible Cause Corrective Action
1. Pump stops or fails to
start
No air supply to pump Make sure compressed air, at proper
pressure, is being supplied to the pump.
Air intake screen clogged Disassemble the air intake fitting and
clean the screen.
Faulty air valve shifting mechanism Check the air valve shifting mechanism.
Repair or replace as necessary.
High pressure line downstream from
pump blocked
Check for blockage at the heater, fluid
filter, gun, nozzle or fluid tip. Clean or
repair components as necessary. Check
the high pressure fluid lines for
blockage.
No hydraulic pressure reading on
gauge
Check the air motor for leakage. Listen
for escaping air from the air valve.
Check the valve shifting mechanism.
Disassemble and repair as necessary.
2. Pump strokes irregularly
when gun is triggered
Air in hydraulic system Purge air from the system.
Clogged or worn ball check valve
inside pump
Perform the flushing procedure as
described in the
Operation section. If
the problem persists, disassemble the
pump hydraulic section and repair it.
Air motor or valve leak Check the air motor and valve operation.
Repair or replace as necessary.
Air volume to pump is inadequate Refer to the Specifications section for
requirements. Correct if necessary.
Partial blockage in hydraulic system Check for blockage at the heater, fluid
filter, gun, nozzle or fluid tip. Clean or
repair components as necessary. Check
the high pressure fluid lines for
blockage.
3. Pump output is below
specifications, or pump
surges
Material being pumped is too viscous Lower the viscosity of the material.
Circulation or drain valve defective Disassemble and clean the valves.
Repair or replace parts as necessary.
Nozzle size, number of guns in
system exceeds pump capacity
Decrease the nozzle size or number of
guns in the system. Add another pump
to the system if necessary.
2. Troubleshooting Charts