TM 10-4610-232-12
Table 4-2. Unit Troubleshootlng Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
2. Media fitter inlet valve will not close (system backwash position or system clean position). MEDIA FILTER lN-
LET valve light on (Reference Schematic Diagram FO-1, Sheet 7, schematic Iine 715).
Step 1.
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Step 7.
Step 8.
Step 9.
Check valve for actual position.
(a) Refer to “AUTOMATIC VALVES” general note.
(b) If valve is closed, refer to valve light does not show correct valve position troubleshooting
(malfunction 3).
Turn off the raw water pump circuit breaker CB4, the booster pump circuit breaker CB5, and the high
pressure pump breaker C (Reference Interconnection Diagram FO-2, Sheet 10). Disconnect the
backwash chlorine pump, connector J45 (Reference Interconnection Diagram FO-2, Sheet 10). Dis-
connect the media filter inlet connector J39. Set the control panel up in SYSTEM CLEAN and push
lNITIATE. Check for 110-120 VAC across J39D and J39E (Reference Interconnection Diagram
FO-2, Sheet 15).
If voltage is not present, go to step 7.
Drain the media filter down until water stops coming out of the media filter top drain. Set the contol-
panel up in SYSTEM BACKWASH and push lNITIATE. Observe the BACKWASH AIR INLET valve
light on the control panel and check for 110-120 VAC across J39D and J39E when it comes on.
(a)
If the backwash air valve light does not come on, refer to backwashing circuit troubleshooting.
(b) If the backwash air Iight comes on and there is no voltage, go to step 7.
Reconnect J39 and check for 110-120 VAC across terminals 4 and 5 on the valve. Follow the control-
panel setup as in either step 2 or 3 above when checking voltage on the valve.
If no voltage is present at the terminals, replace the valve cable and connector (para. 4-47).
CAUTION
Even after closing the bbckvalve in the next step there will be 85 psig (586 kPa) air in
the tubing to the automatic valve. Slowly back off the tubing nut at the block valve to
relieve air pressure before removing the air tubing at the automatic valve.
Cbse the air block valve at the air manifold for the media fitter feed valve. Remove the air tubing from
the valve and check that air is being supplied to the valve by opening the air block valve.
If air does not come out the tubing with the air blockvalve open, find the blockage in the air tubing
and repair it (paras. 4-24 and 4-68).
Check the wiring on the valve for damage or looseness.
(a) Repair any damage to the wiring (para. 4-47).
(b) If the wiring is okay, replace the air control relay and solenoid valve (para. 4-47).
Remove connector P14 (Reference Interconnection Diagram FO-2, Sheet 15) from the control panel.
Turn off the raw water pump circuit breaker CB4, the booster pump circuit breaker CBS, and the high
pressure pump breaker CBS. Disconnect the backwash chlorine pump, connector J45. Set the control
panel up in SYSTEM CLEAN and push INITIATE. Check for 110-120 VAC across J14R and J14S
(Reference Interconnection Diagram FO-2, Sheet 9).
If voltage is not present, notify direct support maintenance.
Drain the media filter down until water stops coming
out of the media fitter top drain. Set the control
panel up in SYSTEM BACKWASH and push INTIATE. Observe the BACKWASH AIR INLET valve
light on the control panel and check for 110-120 VAC across J14R and J14S when it comes on.
(a) if the backwash air valve light does not come on, refer to ‘media filter backwashing circuit
troubleshooting.
(b) If the BACKWASH AIR light comes on and there is no voltage, notify direct support mainte-
nance.
Check for continuity fromP14R to J39D and from P14S and J39E. Power off. Replace the cable and
connectors as required (para. 4-27).
4-52
Change 1
