Hach QC8500 Series 2, User Manual

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Maintenance
5.2 System shutdown procedure
To shutdown the system:
1. To use a manifold with a column, such as the cadmium column for nitrate, take the
column off-line by rotating the switching valve to the bypass position. If the manifold
has a column, but does not have a switching valve, turn off the pump and replace the
column with a piece of Teflon tubing. Restart the pump.
Note: Some methods require certain reagents (typically, the buffer) to be removed last. Check
the QuikChem method for instructions.
2. Remove the reagent lines from each reagent and rinse off the lines and glass weights
before placing them into the rinse solutions.
3. If the QuikChem method recommends a rinse solution, place all reagent transmission
lines into the solution and pump for 5 minutes at standard speed.
Note: This is a critical step in the preventive maintenance of the manifolds.
4. Place transmission lines into deionized water and allow the system to rinse for 5 to
10 minutes at standard speed.
5. Remove the transmission lines from the deionized water and allow all liquid to be
pumped out of the manifold. An exception can be made if the manifold has a dialysis
block. In this case, leave all reagent lines in deionized water.
6. Turn off the pump and release the pump tube cartridges ( section 3.2 on page 16 ).
7. Switch off the master power strip after closing all files in the computer properly.
Note: If a lower set-point temperature is not specified in the software, the heater controller will
remain at the original set temperature. If the method requires a temperature higher than 60º C,
lower the temperature setting to 60º C or less before turning the system off.
5.3 Manifold removal
To remove the manifold:
1. Rinse the manifold according to section 5.2 .
2. Detach the manifold tubing from the manifold fitting that is connected to port 3 at the
injection valve. Leave the piece of tubing attached to the injection valve.
3. Detach the output of the manifold from the union on the flow cell tubing, leaving the
union connected to the flow cell flare.
4. Remove the back-pressure loop, if necessary.
5. Detach heating unit tubing from the manifold, if necessary.
6. Remove all manifold pump tubes from cartridges.
7. Remove the interference filter from the detector module.
8. Remove the sample loop from ports 1 and 4 of the valve.
9. Remove the manifold from the channel.
System unit Keep dry and clean X
Computer Clean hard drive X
Table 11 Maintenance schedule (continued)
Component Service Daily Weekly Monthly
Every 6
months
Yearly