TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
(a) If the outer pointers do not read as listed above, adjust them by turning the time adjustment knob to
the correct setting.
(b) If the inner pointer on any timer does not match the outer pointer, replace that timer (para. 2-22).
7. Backwash cycle phase 1 (drain down). (Ref. schematic diagram FO-1, sheet 8, schematic lines 802-804 and schematic
diagram FO-1, sheet 7, schematic lines 702-706).
Step 1. Open the media filter vent valve and start the raw water pump in system “NORMAL”. Run the pump until the
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Step 7.
Step 8.
media filter is full of water, Turn off the raw water pump, disconnect connector J48 (REF: Interconnection
diagram FO-2, Sheet 15) from the filter flush valve, initiate filter “BACKWASH”, and open the media filter top
drain valve. Check for 110-120 VAC across pins J48D and J48E.
If voltage is present, close the media filter drain valve (make sure the filter is full of water, as described
above, first) and go to step 3.
Reconnect J48 and watch the operating stem on the filter flush valve. It should be in.
(a) If the stem is not in, refer to media filter flush valve troubleshooting.
(b) If the stem is in, close the media filter drain valve. Make sure the media filter is full of water as described
.
above and go to step 9.
Shut down the ROWPU and open the control panel. Restore power to the control panel. Turn off the raw
water pump circuit breaker CB4 and the boost pump circuit breaker CB5 (REF: Interconnection diagram
FO-2, Sheet 10). Disconnect the backwash chlorine pump, connector J45 (REF: Interconnection diagram
FO-2, Sheet 15). Set the control panel up in system “BACKWASH” and push "INITIATE". Check that the
indicating plunger on relay K2 (REF: Interconnection diagram FO-2, Sheet 6) is in.
If the plunger on K2 is not in, refer to operation mode circuit troubleshooting.
Shut down ROWPU and generator. Refer to electrical drawings in Appendix E and check continuity,
point-to-point, from CB9 (REF: interconnection diagram FO-2, Sheet 8) (wire #264) to relay K2(C1X),
schematic line 702. Depress the indicating plunger on K2 when checking its B3Y/B3X contact. Push PB16
(REF: Interconnection diagram FO-2, Sheet 12) during testing to make sure its contact is open in one position
and closed in the other.
(a) Repair any loose or damaged wires (para. 2-20).
(b) Replace relay K2 if its B3Y/B3X contact is open with the plunger out or if it is closed with plunger in
(para. 2-23).
(c) Replace PB16 if it is closed in both switch positions or open in both positions (para. 2-22).
Check continuity, point-to-point, from CB9 (wire #264) to J14B (REF: Interconnection diagram FO-2, Sheet
9). Depress the indicating plunger on K3 (REF: Interconnection diagram FO-2, Sheet 6) when testing its
contact.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K3 if its C1Y/C1X contact is open with the plunger in or closed with plunger out (para.
2-23).
(c) Replace/repair connector J14 if faulty (para. 2-21).
Check continuity, point-to-point, from CB9 (wire #264) to relay K15(B4X) (REF: Interconnection diagram
FO-2, Sheet 7). Depress the indicating plunger on K2 when testing its contact.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K2 if its B4Y/B4X contact is open with the plunger in or if it is closed with the plunger out
(para. 2-23).
Check continuity, point-to-point, from relay K15(B4X) to connector J14B. Depress the indicating plunger on
relay K11 (REF: Interconnection diagram FO-2, Sheet 6) when testing its contact.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K11 if its contact is closed with the plunger out or open with the plunger in (para. 2-23).
Check continuity, point-to-point, from CB9 (wire #264) to J14B. (Schematic line 706.) Depress the indicating
plunger on MS8-1M (REF: Interconnection diagram FO-2, Sheet 10) when testing its contact.
(a) Repair any loose or damaged wire (para. 2-20).
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