Hach APA 6000 Maintenance Et Dépannage page 20

6. Examine the rotary valve.
• Premature wear may occur in the valve. Replace the valve rotor
and examine the stator for scratches. Refer to
rotor on page 10.
• Clean or replace a tube fitting if it has a leak. Refer to
on page 15 and Figure 8
• If the valve module body has a leak, replace the valve module.
Refer to Replace a module
• If reagents or sample are not flowing, the fittings may have been
over-tightened. Cut off the pinched end of the tube and use a new
ferrule. Refer to Figure 7
7. If air moves through the pump piston seals during operation,
examine the sample conditioning block filter. If the filter has a
blockage, replace the filter. Refer to
block filter on page 13. If filter does not have a blockage, replace the
pump piston seals. Refer to
on page 7.
8. If there is fluid leakage around the pump body, replace the pump
piston seals. Refer to Replace the pump piston seals
9. Examine the pressure at the drain block. Refer to
backpressure at the drain block
Aquatrend diagnostics
Use the Aquatrend diagnostic tests to troubleshoot problems.
1. Push MENU and select AQUATREND MENU>AQUATREND
DIAGNOSTI CS.
2. Select an option.
Option Description
DISPLAY TEST Identify if the display is operating correctly. Make
sure that the display shows a checkerboard
pattern.
20 English
Replace the valve
Figure 7
on page 15.
on page 16.
on page 15 and Figure 8 on page 15.
Replace the sample conditioning
Replace the pump piston seals
on page 7.
Examine the
on page 7.
Option Description
KEYBOARD TEST Identify if the keys are operating correctly. Push
any key (i.e., an arrow key or ENTER). Make
sure that the key that is pushed shows on the
display.
MEMORY TEST Start a memory test.
VERIFY PROGRAM Start a verify checksum test.
CHECKSUM
CLEAR ALARM LOG Erase the alarms from the Network and
AquaTrend alarm log.
AQUATREND COLD For Service use only
START
SERVICE MENU For Service use only
Sensor diagnostics
Use the sensor diagnostic tests to troubleshoot problems.
1. Push MENU and select SENSOR MENU>APA6000 #1 APA
6000>SENSOR DIAGNOSTICS.
2. Select an option.
Option Description
HOLD OUTPUTS Hold the recorder analog outputs and alarm relays at
their present values/on-off states for a maximum of
30 minutes.
INTERNAL Set the alarm relay (Alarm A or Alarm B) to energized
RELAY TEST or de-energized for a maximum of 30 minutes. Use a
continuity meter on the NO and NC relay output
terminals to confirm the relay status selected.
INTERNAL Set the recorder output (Recorder A or Recorder B) to
OUTPUT TEST the zero level value (4 mA), half level value (12 mA) or
the full level value (20 mA) for a maximum of
30 minutes. Use this option to confirm operation of the
connected devices.