Nortec Industries Airfog Series - Manual (Page 46)

10-50
Page 39
2008-04-11
C. Repair the identified problems and verify the system is fully operational using the
procedure described in the Start Up section of this guide.
4. UNSCHEDULED MAINTENANCE
A. Normally an unscheduled maintenance activity is initiated by an observation of a leak or
other failure.
(1) The AIRFOG system is to be shutdown in accordance with the procedure
described in the Shut Down section of this guide.
(2) Execute repair action either by repairing the leak or replacement of the suspected
component.
(3) Record the date, nature of the problem, the repair action taken, other pertinent
details and sign the failure report.
(4) Comparison with previous inspection records and failure reports could indicate
systematic problems as compared to random events.
(5) Verify the system is fully operational using the procedures described in the Start
Up section of this guide.
5. VACUUM VALVE TESTING
A. Setup for test:
(1) Adjust air feed pressure from the control panel to 70 psig.
(2) Adjust water feed to vacuum valve to 25 psig.
(3) Adjust vacuum valve regulator to 7 psig. (This adjustment cannot be made until
the system is turned on and a pilot signal of 15 psig or greater is applied.)
(4) Adjust vacuum valve thumb wheel to zero force (spring backed off).
B. While system in operating, visually watch the spray pattern from the nozzles.
C. If the system is completely sealed (no vacuum leaks in the water line) then once the
system is turned on for the first time all nozzles should start spraying starting with the
nozzles closest to the vacuum valve. The negative pressure created in the water line by
the high velocity air exiting the nozzles will cause the water line to fill with water, the
farther the nozzle is from the vacuum valve the longer it will take for the water to reach
that nozzle. Once the system has gone through the priming stage, it should start
spraying within seconds after the system has been turned on after a shut down. The
priming stage should not take any longer than five minutes. If the system fails to fully
prime after five minutes this may indicate a problem.
6. CHECKING FOR VACUUM LEAKS
A. The best way to check for leaks is to disconnect the water line from the vacuum valve
outlet fitting and connect it directly to the water supply line. This will pressure the line
and any leaks should cause dripping allowing location and repair of the leaks.
B. To test the operation of the vacuum valve:
(1) Reduce the control panel pressure to 40 psig.
(2) Adjust thumb wheel tension by turning it in a clockwise direction. There should be