Installation and operating instructions Wilo-Sevio AIR D 25
MAINTENANCE AND REPAIR English
•
A large proportion of fibrous material or sand in
the medium
• Strongly corrosive media
• Highly aggressive media
• For industrial applications
8.1.3. Recommended maintenance measures to en-
sure smooth operation
We recommend installing a manometer in the
inlet pipe leading to the aerator field. The current
pressure immediately indicates smaller faults
which can be remedied accordingly.
Deposits on the diaphragm decrease the air intake
into the medium and the pressure in the aera-
tor field goes up. This leads to a lesser degree of
efficiency in the system. This condition is made
visible by the altered appearance of bubbles on
the fluid surface. In this case, the maintenance
measure “Cleaning the diaphragm surface” must
be performed.
If the aeration system is leaking or a diaphragm
ruptures, the pressure in the aeration system
decreases. This leads to an uncontrolled air intake
and causes the efficiency of the aeration system
to decrease. This condition is also visible on the
fluid surface, when large air bubbles escape. In
this case, the system must be decommissioned
immediately, and a function test with clear water
must be performed to locate the leak.
Regular inspections can therefore largely prevent
major secondary damage and reduce the risk
of total breakdown. Hence, we recommend the
use of remote monitoring for regular inspections
of the air intake. Please contact Wilo customer
service.
8.2. Maintenance tasks
8.2.1. Test run
To prevent damage to the diaphragm, a 10 minute
test run must be performed. Attention must be
paid to ensure that the minimum water level in
the operating space must be >1 m. The air intake
must correspond to the standard loading.
8.2.2. Drainage of the aeration system
Open the valve of the drainage pipe during the
test run. The air supply in the aeration system
causes water/condensate that may be present to
discharge via the drainage pipe.
8.2.3.
Cleaning the diaphragm surface
During operation, the diaphragm surface can get
clogged by deposits. This leads to a decreased air
intake into the fluid and decreases the efficiency
of the aeration system.
To counteract this condition, the diaphragm must
be inflated in short intervals under peak load ac
-
cording to maintenance intervals.
1.
Increase the system pressure for 10 minutes to
the max. permissible value:
•
9“ aerator: 10 Nm³/h
•
12“ aerator: 15 Nm³/h
2. Turn the aeration off for 2 minutes.
3.
Repeat these steps 3 - 4 times.
The max. permissible value for loading must not
be exceeded!
As these maintenance measures contribute
significantly to function reliability and efficiency
of the system, automatic performance of the
maintenance interval is recommended. This can
be ensured by personnel. Contact the manufac-
turer of the operating point to do so.
8.2.4. Mechanical cleaning of the diaphragm surface
1.
Switch off aerator field
2. Drain the basin
3. Rinse the basin and aerator with a high pressure
cleaner
Attention: Do not point high pressure cleaner
at the diaphragm. It could cause damage to the
diaphragm!
4. Perform clear water test and measure air intake.
If the pressure is still high, perform the cleaning
again.
8.2.5. Leakage test of the aerator group(s)
Leaks are made visible on the fluid surface due to
a change in bubble appearance. Check the oper-
ating space from all corners for unusual bubble
formation.
We recommend performing a function test with
clear water for this maintenance measure and
walking the operating space during the process.
8.2.6. Maintenance measures of compressors/fan
Perform all maintenance tasks according to the
devices’ manufacturer’s specifications.
8.2.7. Filter replacement
If filters are used in the air supply, they must be
cleaned or replaced regularly. Please refer to the
respective filter documentation for more informa
-
tion.
