PRESSURE GAUGES
TM 10-4610-232-34
Table 2-1.
Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. Pressure gauge does not register pressure (stays on zero).
WARNING
The ROWPU operates with high pressure water and air. Make certain all vents and drains
are open and pressure relieved before disconnecting gauges.
For Model WTA-060, shut down the ROWPU. Remove the pressure sensing line from the gauge and hold it so that it will
not spray personnel or equipment. Start the ROWPU and check that water comes out of the disconnected tubing.
(a)
Replace the pressure gauge if water comes out of the tubing (para. 2-19).
(b) If water does not come out of the tubing, check for blockage in the line to the gauge.
For Model ROWPU-1, check for water in gauge by opening drain valve to check that water comes out of the drain
valve.
(a)
Replace the pressure gauge if water comes out of the tubing (para. 2-19).
(b) If water does not come out of the tubing, check for blockage in the line to the gauge.
2. Pressure gauge does not zero.
WARNING
The ROWPU operates with high pressure water and air. Make certain all vents and drains
are open and pressure relieved before disconnecting gauges.
Check that there is no pressure on the gauge. Shut down the ROWPU and open all vents and drains. Carefully start
disconnecting the sensing line from the gauge.
Replace the gauge if it does not zero with the sensing line disconnected (para. 2-19).
3. Pressure gauge suspected of not being accurate.
WARNING
The ROWPU operates with high pressure water and air. Make certain all vents and drains
are open and pressure relieved before disconnecting gauges.
Test gauge (para. 2-19). Disconnect sensing line from gauge and remove gauge. Use a dead weight tester and check
gauge for accuracy.
Replace gauge if it does not meet test standards listed below. Low pressure gauge ±5% of Ml scale.
High pressure gauge: ±1.5% of full scale from 300-900 psig: ±2.5% of full scale from 0-300 and above 900
psig.
4. System pressure gauge media or cartridge pressure gauges fluctuate.
Step 1. Check that the backwash air solenoid valve is not leaking air into the media filter. Close the air block valve at
the air manifold for the backwash air solenoid valve. Operate for 10 minutes and watch the gauge fluctuation.
If the fluctuations stop, refer to water in the air system troubleshooting of the backwash air solenoid valve
(malfunction 5, -12 manual).
Step 2.
Check high pressure pump inlet and outlet valve discs and spring.
(a)
Replace any valve discs that show radial or circumferential cracks, pitting other than normal surface wear,
nicks, gouges, elongated center holes, and a chalky feeling/appearance when scratched with a fingernail
(para. 2-78).
(b)
Replace any broken valve springs (para. 2-78).
2-8
Change 3
