-9-
•
Clean the filter with a brush or cloth, or replace it
•
Re-install the filter and screw the filter lid back on
Checking the valve
•
Remove the vent plug from the valve cover.
•
Check that the valve spindle moves easily by raising and lowering it with the threaded rod.
Putting back into service
•
according to Commissioning paragraph
Functional check of the valve
The pressure retention valve must be set for the check to allow the inlet pressure to open the valve (please
refer to chapter
Regulation of pressure retention
)
•
Valve 1403:
Apply power to the solenoid valve (9) (
➔
solenoid valve has flow, opens).
•
Valve 1404:
Leave solenoid valve (9) inactive (
➔
solenoid valve has flow, is open).
•
Slowly
close the ball valve (2C); the valve must close.
•
Slowly
open the ball valve (2C); the valve must open.
2.3 4 to 5-year maintenance
Dirt trap (main line)
•
Unscrew the lid
•
Clean or replace the filter
•
Install the filter and screw the lid back on
Filter (control line)
•
Unscrew the lid of the filter
•
Clean or replace the filter mesh
•
Re-install the filter and screw the filter lid back on
Base valve (see chapter: Repair kits and spare parts)
•
Loosen the screw connections and remove the complete control line.
•
Dismantle the optical position indicator or assembled accessories and replace the gaskets.
•
Undo the screws of the valve cover and remove the cover.
•
Visually inspect all inner components for wear, dirt and scaling
•
Clean the inner components, the seat and the inner surfaces, including the cover
•
Dismantle the spindle guide in the body, flush the body interior.
For valves DN 40 to DN 100 (from 2012 on) and DN 125 to DN 200 (from 2014 on) the spindle guide
is dismantled from the inside. Here the thread of the spindle guide and the base valve must be
extremely clean
. Grease the thread thoroughly (e.g. Foodgrease Aqua, Art. no. 5292, see chapter
“Control line individual parts and accessories”).
•
Replace the diaphragm, the O-ring and the seat seal.
•
Grease the spindle guide area with a grease suitable for contact with food (e.g. Foodgrease Aqua).
Check the easy movement of the spindle by lifting and lowering with the spindle lifting tool (article
number 1199, see
chapter “Control line individual parts and accessories”).
•
Reassemble the base valve (see table in the annex for torques). During the assembly, the easy
movement of the spindle must be checked with the spindle lifting tool by lifting and lowering
several
times
.
Disassembling the control valve (see chapter: Repair kits and spare parts)
•
Switch over the clamping and adjusting lever
•
Turn the adjusting lever to the left until no resistance can be felt from the spring
•
Undo the housing screw
•
Loosen the guide pin and the sealing plate
•
Replace the diaphragm, the O-ring and, if necessary, the seal support
•
Visually inspect the inner surfaces of the housing, and clean if necessary, including the cover
