Troubleshooting
309738L
45
Dispense Valves
Problem
Cause(s)
Possible Solution(s)
Valve not opening
Air not getting to open port
Verify air pressure solenoid
No “Gun On” signal from automa-
tion unit
Check input from automation unit
No output from system I/O board
Check output from system I/O
board; verify that it is on
Valve not shutting off
Air not getting to close port (except
AutoPlus valve)
Verify air pressure to solenoid
Verify solenoid operation
Verify air line routing and connec-
tions
“Gun On” signal from automation
unit is on
Check input from automation unit
Check output from system I/O
board; verify that it is on
Sluggish open/close
Air pressure low
Verify air pressure is above 60 psi
(0.4 MPa, 4 bar)
Needle/seat worn
Rebuild valve; replace needle/seat
Pressurized material past the valve
shut-off is escaping
Reduce running pressure
Reduce nozzle length
Increase nozzle orifice size
Material leaks from back of valve
Shaft seal is worn
Rebuild valve; replace seals
Air leaks from dispense valve
Loose air connections
Check air connections; tighten if
necessary
Worn piston o-ring
Rebuild valve; replace piston o-ring
Dispense valve does not heat
Temperature controller turned off
Verify zone #4 is on through the
user interface
Loose electrical connections
Verify connection between outlet
hose and valve connector
Verify connection between outlet
hose and main enclosure through
extension cord
Blown fuse
Check/verify fuse in Electric Heat
box
Broken heat cartridge
Check/verify heater resistance
Broken sensor
Check/verify sensor resistance
