TM 10-4610-232-12
Table 4-2. Unit Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
2. Booster pump noisy.
Step 1. Check mounting hardware.
Tighten, if loose.
Step 2. Check the filter pressure gages.
(a) If the gages show normal operating pressures (the ROWPU is operating as if nothing was wrong),
replace the booster pump and motor assembly (para. 4-43).
(b) If the gages are at or near 0 psig (0 kPa) and the system is in “NORMAL” mode, notify direct
support maintenance to troubleshoot the feed low pressure switch for correct operation.
(c) If the gages are at or near 0 psig(0 kPa), the system is in “NORMAL” mode, and the forward flush
valve IS open, troubleshoot the raw water pump for “low flow, low pressure” (malfunction 6).
(d) If the gages are at or near 0 psig(0 kPa)andthe system is in “CLEAN” mode, notify direct support
maintenance to troubleshoot, in order, the feed low pressure switch, clean/flush tank low level
switch, and the clean/flush tank valve for correct operation until the problem is found.
(e) If the gages are at or near 0 psig (0 kPa), the system is in “BACKWASH” mode, and the raw water
pump is running, troubleshoot the raw water pump for “low flow/low pressure’’( malfunction 6).
(f) If the gages are at or near 0 psig (0 kPa) and the system is in the last phase of backwashing,
troubleshoot the clean/flush tank low level switch (malfunction 7 in level switch troubleshooting)
and the clean/flush tank outlet valve (malfunction 16 in automatic valve troubleshooting.
Step 3. Remove inlet piping from booster pump and check for foreign objects (para. 4-43).
(a) Remove foreign objects, if present.
(b) Replace booster pump/motor assembly (para. 4-43).
3. Booster pump continues to run when raw water is not supplied to the ROWPU.
Check operating conditions.
NOTE
This situation can occur if the media filter has an air blanket and the raw water pump
is shut down or stops running for some reason. The air blanket slowly drops in
pressure and the booster pump will keep running until the pressure drops far enough
to trip the feed low pressure switch. There is no problem as long as the booster pump
shuts down when the pressure drops to about 7 psig (48 kPa).
If the pump does not shut down, notify direct support maintenance to troubleshoot the feed low
pressure switch.
4. Booster pump is started in “CLEAN” mode, but no pressure is observed at the cartridge filter gage.
Step 1. Check that booster pump is running by opening the access panel and observing pump.
If the pump is not running, refer to booster pump electrical troubleshooting (malfunction 6).
Step 2. Operate ROWPU in “NORMAL” mode. Check pressure gages for operation.
(a) If the gages don’t show pressure, notify direct support maintenance.
(b) If the gages are operating correctly, check the cleaning bypass piping and the clean/flush tank
outlet piping for plugging (para. 4-45).
5. Booster pump does not shut down when running off of the clean/flush tank and the tank is empty.
Visually observe if the clean/flush tank low level light and the feed pressure Iow light on the control panel are lit.
(a) If the clean/flush tank low light is not lit, refer to level switch troubleshooting (malfunction 7).
(b) If the clean/flush tank low light is lit, notify direct support maintenance to troubleshoot the clean/
flush tank low level control circuits.
(c) If the feed pressure light is lit, notify direct support maintenance to troubleshoot the low feed
pressure shutdown circuits.
(d) If the feed pressure light is not lit, notify direct support maintenance to troubleshoot the feed low
pressure switch.
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