Graco VPM 12, Instructions Manual

Page: 51 / 88

Troubleshooting
313875J 51
Troubleshooting
For information about ADM error and event codes see
Appendix D - ADM Event and Error Codes Overview ,
page 69.
Before performing any troubleshooting procedure:
1. Perform Pressure Relief Procedure on page 46.
2. Turn Main Power Switch to the OFF position.
3. Allow equipment to cool.
Try the recommended solutions in the order given for
each problem to avoid unnecessary repairs. Also, deter-
mine that all circuit breakers, switches, and controls are
properly set and wiring is correct before assuming there
is a problem.
Light Tower (Optional)
Errors include advisories, deviations, or alarms, so
green will only be on when none of these occur. A yellow
light can be on at the same time as red (flashing or solid
on) when an advisory exists at the same time as a devi-
ation or alarm.
Common Problems
Signal Description
Green on only System is powered up and there are
no error conditions present
Yellow on An advisory exists
Red flashing A deviation exists
Red on The system is shut down due to an
alarm occurring.
Problem Cause Solution
General
Display Module completely
dark No power Verify main power switch is ON
Thrown circuit breaker Check machine breakers and reset
Loose connection Tighten 5-pin cable on Advanced Display Module
Bad display module Replace Advanced Display Module
No or incorrect amount of
material dispensed from
either side Tank empty Install new drum of fluid
Air in material Prime the machine
Significant material leaking
from pump seal Pump shaft worn and/or shaft seal
worn Remove pump shaft assembly and reinstall, see
pump manual for instructions and rebuild kit
Material dispensed not cor-
rect weight Specific gravity of one or more of the
two materials has changed since cali-
bration Perform calibration procedure
Check valve malfunction Remove check valve; clean or replace as necessary
Piston worn or broken Replace piston
Proportioning System
Proportioning pump does not
hold pressure when stalled Pump piston or intake valve leaking 1. Observe gauges to determine which pump is los-
ing pressure.
2. Determine in which direction the pump has
stalled by observing which directional valve indi-
cator light is on.
3. Repair the valve.