TM 10-4610-241-24
TO40W4-13-42
Table 2-2. Unit Troubleshooting-continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
PIPING INSTALLATION - continued
14. BACKWASH CYCLES TOO SHORT OR TOO LONG.
NOTE
Normal backwash cycles are as follows. Deviations from these times in excess of 20%
should be considered abnormal:
(Models WPES-10, WPES-20 and WPES-30 only)
Cycle 1 - Slow Backwash
2 Minutes
Cycle 2 - Fast Backwash
6 Minutes
Cycle 3 - Slow Backwash
2 Minutes
Cycle 4 - Rinse
2 Minutes
(Models H-9518-1, H-9518-2, and H-9518-3)
Cycle 1- Backwash
12 Minutes
Cycle 2- Rinse
4 Minutes
Step 1.
Models H-9518-1, H-9518-2, and H-9518-3:
If times are abnormal, replace the timer. Refer to Paragraph 2-68.1
Step 1.
Models WPES-10, WPES-20 and WPES-30 :
Remove plate for access to DIP switches and compare switch settings with illustration.
a.
If settings agree with illustration, replace timer. Refer to Paragraph 2-68.
NOTE
To change position of switches, use a pointed object (small screwdriver or pencil will do)
and push in at bottom or top of switch.
•
If switch is in ON position, push in at bottom to change it to OFF.
•
If switch is in OFF position push in at top to change it to ON.
b.
If settings are different, change switch settings to agree with settings in illustration.
Step 2. Operate ROWPU in backwash mode and time each cycle.
If malfunction continues, replace timer. Refer to Paragraph 2-68.
2-22 Change 1
