AEC Continuous Vacuum/Pressure Conveying Systems - Manual (Page 54)

Single- and Dual-Blower Continuous Vacuum/Pressure Systems Page 53
Note: The counterbalance should be adjusted so the flapper remains open about 1 /
2
” (13
mm) when not under vacuum.
6-5 Service Procedures
This section lists major system service areas.
Cleaning Pressure Unit Inlet Filters
Some models have a screen over the air inlet on the upper valve. Wipe it off or
vacuum it as needed.
For other models, perform the following procedure to clean the inlet filter:
• Shut down the vacuum unit by pressing Purge Stop ( 3B ).
• When the unit stops, open the disconnect switch ( DISC ) at the control
enclosure and the disconnect switch at your power drop.
• Remove the nut and washers that hold on the filter cover, and take off the
cover.
• Remove the retainer and the filter element, and separate the two.
• Wash the filter element in cold water and a mild detergent. Rinse and dry it
thoroughly before you reinstall it.
• Place the element and retainer back in the filter case and refasten the cover
with the nut.
Replacing Mufflers
The muffler is located under the vacuum unit base at the discharge of the lower
valve. Use the following procedure to replace it:
• Shut down the vacuum unit by pressing Purge Stop ( 3B ).
• When the unit has stopped, open the disconnect switch ( DISC ) at the control
enclosure and the disconnect switch in your power drop.
• On solid state units, turn off the compressed air to the unit.
• Remove the coupler connecting the muffler-to-line adapter to the
blowthrough adapter.
• Uncouple any copper air tube from the muffler.
• Loosen the setscrews securing the valve-to-muffler adapter to the lower
valve.