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HHCompact Air Handling Units
Maintenance and Operation
Instructions
6.1 - General
The smooth inside and outside finish of the panels makes
maintenance very simple.
For dry sections: twice a year thoroughly check the inside
and outside of the AHU casing. For maintenance of wet
sections (coolers) please refer to the air handling section
concerned. All work must be carried out by sufficiently
trained personnel.
All applicable personal safety devices must be used
to ensure safe working conditions. Safety gloves and
glasses must be worn for all maintenance operations. A
respiratory protection mask must be worn when changing
the filters.
No holes must be drilled into the AHU, to prevent leakage
from the AHU, cooling coils and heating coils and damage
to the wiring.
6.2 - Casing panels
6.2.1 - Inside installation
a) Internal inspection of the casing of double-skin
panels and of all dry parts.
Remove contamination with water and a mild (pH
neutral) household soap solution. Where damage of
the paint finish has occurred, if necessary remove
rust and touch up with good quality anti-corrosive
primer and paint. The outdoor air intake sections can
show signs of corrosion as they contain wet parts
and are affected by mist, rain and air pollutants.
b) Outside inspection of the coating.
If damage to the paint treatment has occurred,
remove the rust (if necessary), and touch up with
good quality anti-corrosive primer and paint.
6.2.2 - Outside installation
Check the sealed joints of AHUs installed outside and if
required seal with a UV-resistant and paintable kit. Repair
damage as described for inside installation. Check the roof
for leaks and if necessary, repair these.
6.3 - Doors and access covers
Check locks and hinges of all doors and access covers.
Check that the bolt of the internal roller is still correctly
tightened.
6.4 - Flexible connections
Check the flexible connections for damage.
6.5 - Earthing
Ensure that the unit is earthed and installed correctly.
6.6 - Dampers
CAUTION:
•
When working on damper registers it is possible for
fingers to become trapped.
•
During cleaning of the damper fins the AHU must be
de-energised to prevent unexpected closing of the
dampers.
•
During repairs to the servo, the AHU must be
deenergised to ensure the connection cables are not
live.
•
Lubrication of the dampers is not required. Remove
excess contamination by cleaning with compressed
air and possible cleaning with water and a mild
household soap solution. Ensure that the damper
blades run free in the casing.
6.7 - Outdoor air intake
The outdoor air intake is contaminated by pollution
taken in with the air. The maintenance interval must be
observed, as irreparable damage of the panels might
otherwise occur. Clean the outdoor air intake well and
repair damage as described in point 6.2.1. Ensure that no
moisture (droplets) is taken in. If there is still moisture,
ensure that this is corrected by changing the outdoor air
intake duct.
6.8 - Filters
ATTENTION:
•
When changing the filter there is a danger of viral
and bacteriological contamination. Use of suitable
gloves, face masks and safety glasses is compulsory.
Wearing safety glasses is compulsory. The face mask
must be minimum P2. The gloves must be liquid-
tight.
•
The filters must be fitted in the correct manner (air
direction).
•
The bottom under the filter may be highly
contaminated. This dirt must removed during every
inspection.
Any corrosion of the bottom must be removed
immediately and repaired with an anti-corrosion
agent and/or coating.
•
Filters that are too dirty also increase the resistance
(pressure differential) of the filter and can increase
power consumption. The fastening frame of the filter
may fail if the pressure differential over the filter is
excessive.
•
The filters must be inspected once a month for
excess pollution, pressure loss, damage and seating
of the slide-in filters or built-in frames. With slide-
in filters ensure that the filters have been correctly
positioned and have been pushed well against each
other from below. When replacing built-in filters you
must ensure that the filter has been pushed well
against the sealant. Filters must be replaced at the
required intervals.