4 MAINTENANCE
4.1 Genaral rules
The valves DA 400, due to construction methods and materials used, are easy to
maintain. Minimal maintenance, simple, accurate and allow a continuous operation
lasting over time and adjust the valve, maintaining unchanged performance.
4.2 Valve disassembly
Before disassembling the valve:
1) Clean the outside
2) Release the pressure from the system
3) Loosen the adjustment lock with a key 13. Be careful because the spring is pushed
(see Fig. 1)
4) Unscrew the nozzle with a 9 or a 10-key (see Fig. 2)
5) Remove the spring
6) Needle nose pliers, pull the needle narrow (see Fig. 3)
7) Remove the protective plastic sleeve with a screwdriver and unscrew and remove
the sleeve from the valve body. (see Fig. 4)
4.3 Valve Re-assembly
After it has been cleaned thoroughly and have replaced all the damaged parts
(especially the seals and scraper mounted below the compass). Reassemble in the
reverse order of disassembly with little lubrication of the parts and the seals with
grease.
PROBLEM
POSSIBLE CAUSE
SOLUTION
Nothing or little fluid
Valve does not receive the command
Check the control (solenoid) of valve. Perform
a manual test.
The pressure of the fluid is too low
or absent.
Check the pressure of the power supply fluid
and possibly increase it.
The nozzle is clogged
Remove and clean the nozzle.
The filter is dirty (if any)
Clean or replace the filter.
A tube is bent
Check the fluid supply pipe
Actuating pressure is not sufficient
Verify the actuation pressure (6 bar)
Residual fluid in the system to clean
Remove any solid particles
Flow of fluid compass
Moulded gasket damaged
Replace the molded seal
The nozzle drips also
if the valve is not pilot
Presence of dirt in the nozzle
Clean or replace nozzle
The valve opens late
Pressure drive is not enough
Check the operating pressure (6 bar)
O-ring on the piston damaged
Replace O-ring on the piston pneumatic
5 TROUBLESHOOTING
5.1 Problems and solutions
The search for defects in the operation should be performed only by personnel qualified respecting the safety rules
in force.
fig. 1
fig. 2
fig. 3
fig. 4
Installation and maintenance guide
