Taylor-Wharton Auto Fill Laser Pak - Manual (Page 23)

23
MAINTENANCE
Routine inspections of the system are recommended. The need for maintenance usually becomes apparent
from inspection and indications of improper operation. Typical trouble indications would be error alarms,
leakage from valves or piping connections, and excessive venting through relief valves. Keep a permanent log
of all inspections and repairs performed. Such a log can be valuable in evaluating performance and scheduling
maintenance.
Date Nature of Work (Describe in Full) Remarks Servicemen's Signature
Figure 15: Inspection and Repair Log (Sample Form)
Always observe the safety precautions at the front of this manual and follow the instructions given in this
section. Before working on piping, isolate the piping section to be repaired from the vessels, and relieve
pressure on the component or piping.
Do not allow unqualified persons to attempt repairs on this equipment. Field repairs to instruments and
controls must be made by a qualified electrician. Refer to the Trouble-Remedy Guide in this manual for
assistance in troubleshooting.
Leak Test
After making repairs requiring disassembly or replacement, leak test all valves or piping joints that were taken
apart and reconnected. Apply leak detector fluid to the test surface. Large leaks instantly form large bubble
clusters, while fine leaks produce white foam that builds up more slowly. All leaks must be repaired and
retested before the system is returned to service.
Solenoid Valves
The most common trouble with a solenoid valve will be leakage at the stem packing. Packing leaks are
usually indicated by ice emerging from the packing gland or retainer threads. If tightening cannot stop
packing leakage, replace the packing. Use preformed packing ordered from the valve manufacturer.
The solenoid valves may be rebuilt without removing the valve body from the system. Rebuild kits are
available from the solenoid valve manufacturer. If necessary the valve may be completely replaced.
Compression type fittings make valve replacement relatively easy. It is not necessary to cut, weld, or braze
the piping in order to remove the valves.