Model A7AA Air Assisted Airless Gun
13
2000 Nordson Corporation
All rights reserved
108 046C
Issued 1/00
Manual 4-20
WARNING: Allow only qualified personnel to perform the
following tasks. Follow the safety instructions in this document
and all other related documentation.
This section contains troubleshooting procedures. These procedures
cover only the most common problems that you may encounter. If you
cannot solve the problem with the information given here, contact your
local Nordson representative for help.
The following table lists possible A7AA malfunctions.
Problem
Possible Cause
Corrective Action
1.
Leaking around the
nozzle or nozzle
retaining nut
Dirty or damaged nozzle seal or
sealing surfaces
Relieve pressure to the system.
Remove nozzle retaining nut. Clean or
replace nozzle, nozzle seal, or ball and
seat.
2.
Leaking through
exhaust holes in gun
body directly behind
fittings
Worn packing cartridge
Replace packing cartridge and seal kit.
3.
Spitting
Dirty or worn ball tip or seat
Clean or replace ball tip and seat.
Long trigger air lines
Mount solenoid on gun or as close as
possible. Use optional dump valves or
air release valves. Refer to the
Options
section.
Air trapped in the fluid system
Circulate fluid for several minutes to
purge air from the system.
Air overlap adjustment is incorrectly
adjusted
Adjust packing cartridge adjuster.
4.
ON/OFF cycle response
poor or non-existent
Air piston assembly worn or out of
adjustment
Adjust or replace air piston assembly.
Low air pressure to air solenoid
Increase the air pressure. The air
pressure should be between
2.76–4.14 bar (40–60 psi).
Long trigger air lines
Mount the solenoid on the gun or as
close as possible.
High fluid pressure
Reduce the fluid pressure at the pump.
The maximum pressure is 117 bar
(1700 psi).
6. Troubleshooting
Troubleshooting Chart
