Maintenance; Intervals For Cleaning And Maintenance; Cleaning And Replacing The Filter; Cleaning The Measuring Cell - Grundfos AQC-D13 Montage- Und Betriebsanleitung

12. Maintenance

Warning
Prior to cleaning and maintenance: Switch off the
system as described in section
Make sure that the mains is switched off at all poles!

12.1 Intervals for cleaning and maintenance

• Clean the filter
– if high contamination is evident, or if the pressure drops
considerably.
• Clean the whole measuring cell
– if high contamination is evident
– if faults occur
– before start-up after long-term stop.
• Replace the electrodes.
– Grundfos recommend to replace the reference electrode
and the redox or pH electrode after 12 months.
– The measuring electrode is wear-resistant.

12.2 Cleaning and replacing the filter

• Required tools and aids:
– water
– soft brush.
Caution
Do not completely unscrew the sampling cock (I)!
1. Unscrew the filter holder (H).
2. Remove the filter.
3. Clean the filter and filter holder with water. Use a soft brush, if
necessary.
4. Replace O-ring, if damaged.
5. Insert filter into filter holder.
6. Screw back the filter with filter holder.
After cleaning, check the sample water flow rate.
Note
Adjust, if necessary.
H
I
Fig. 22 Filter

12.3 Cleaning the measuring cell

12.3.1 Removing the measuring cell
Caution
11.3 Switching off !
Caution
1. Empty the measuring cell.
2. Remove the cover, remove the electrodes and sensors.
Caution
3. Unscrew the measuring cell from the mounting plate.
12.3.2 Dismantling the measuring cell
1. Unscrew the filter holder (H).
2. Remove the filter.
3. Remove the cylinder (M).
4. Carefully remove the rising pipes.
5. Remove the connection parts.
6. Completely unscrew the regulation of sample water quantity
12.3.3 Cleaning the measuring cell
•
•
•
Caution
Caution
1. Clean the metal surfaces of the measuring electrode (J) with
2. Carefully clean all plastic parts with soap suds.
3. Use hydrochloric acid (5-10 %) for deposits.
4. Carefully rinse all parts with clean water.
5. Replace any damaged parts.
The measuring cell must only be removed by
authorised personnel.
Do not completely unscrew the sampling cock (I)!
– Completely empty the measuring cell through the sampling
cock (I).
– Loosen the water connections (E, F).
– Remove the cover (L).
– Leave the pH electrode (A) and redox electrode (B) in the
cover.
– Clean the pH electrode (A) and redox electrode (B).
Place the protective caps onto the electrodes.
– Carefully lay the cover (L) down to the side.
– Remove the measuring electrode (J) and the reference
electrode (K).
– Clean the reference electrode (K). Attach the protective cap
onto the electrode.
– The protective caps must be filled with 3-molar potassium
chloride solution.
Observe the installation and operating instructions of
the electrodes!
– Store electrodes with protective caps in a dry place.
(G).
Required tools and aids:
– soap suds, diluted hydrochloric acid (5-10 %), water
– abrasive domestic cleaning agent (for instance ATA, VIM).
The measuring cell can be cleaned with conventional soap
suds.
If high contamination or furring is evident, clean the
dismantled measuring cell briefly with diluted hydrochloric acid
(max. 5-10 %).
Warning
Observe the safety regulations when using
hydrochloric acid!
Wear protective clothing (gloves and goggles) when
cleaning with hydrochloric acid!
Before using other detergents, check the chemical
resistance of the materials.
Do not clean electrodes, filters or other metal parts
with hydrochloric acid.
an abrasive domestic cleaning agent, if there are deposits.
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