Algas SDI TORREXX TX100, Operation & Maintenance Manual

Page: 84 / 98

SOLENOID NOISE
Solenoid valves emit a sound when operated. When energized, they emit a
clicking sound. Also, accompanying the operation of most AC valves, is AC hum.
Whether or not AC hum is objectionable actually depends on the requirements
and opinion of the user. Normal AC hum is the result of the constantly reversing
magnetic field produced by alternating current. The constantly reversing
magnetic field can cause vibrations in the solenoid parts.
1. Solenoid noise due to damage solenoid parts such as bent solenoid base
assembly, stretched return springs, loose parts, etc.
Solution: Inspect valve internals and exterior. Replaced damaged
parts.
2. Solenoid noise due to foreign matter between the core and plug-nut. When
foreign matter is trapped between the core and plug-nut, the core assembly
will rock back and forth at 60 hertz. Eventually, the core and plug-nut face
will be distorted, at which time the noise can continue even though the
foreign material may have been flushed or removed from the valve.
Solution: Replace damaged parts entirely, clean and reassemble.
3. Solenoid noise due to damaged coil. On rare occasions, a severe voltage
spike or over voltage can potentially short a small portion of the coil winding.
This shorting can cause solenoid noise and coil overheating. However, it
would normally lead to rapid coil burnout. The solenoid parts, however,
could be damaged enough that the noise would continue even after the coil
was replaced due to the deformation produced during the peening process.
4. Missing solenoid parts can severely weaken the magnetic circuit. This can
produce a solenoid noise condition. As discussed above, it will probably also
result in coil burn-out.
Solution: Replace damaged parts, replace lost parts, clean and re-
assemble.
In general, when a noise condition has been encountered, the source of the
problem should be determined and eliminated. The valve should then be
thoroughly inspected to insure that it is yet repairable. Most times, simple
installation of a spare parts kit and a solenoid base sub assembly can restore a
valve to like new condition. The restored and reinstalled solenoid valve should
be tested to insure proper operation, and a voltage check should be made at the
solenoid valve while the valve is energized. In addition, a current reading can be
obtained and compared with catalog specifications to verify normal solenoid and
coil operation.
Note: The coil may have been damaged due to excessive current draw of at
damaged shading coil within the solenoid valve. A partial rebuilding of a valve
damaged by a noise condition can prove useless as the noise condition would
continue. The entire valve should be dismantled and inspected and cleaned. All
parts supplied in a spare parts kit should be installed. Further, and additional
solenoid parts damaged by a noise condition such as a solenoid base sub
assembly, should be replaced. Examine valve seating, pistons and the valve
body to verify that they have not been damaged. Damage to major portions of
the valve may make repairing the valve uneconomical.
Should a noise condition be encountered, immediate action may prevent any
damage to the solenoid valve itself.