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Operation and maintenance instructions
Envistar / CRAMO
DSCR111125.01
Air handling with the focus on LCC
Continuous product development may give rise to specification changes without prior notice.
3 Maintenance Instructions
3.1 Filter (code ATEF), disposable type
The air filters in an air handling plant should prevent dust and particles from be-
ing discharged into the building. They should also protect the sensitive compo-
nents inside the unit, such as coils and heat exchangers, from becoming fouled.
The collecting efficiency between different types of filter may vary considerably.
The capacity to accumulate particles also varies substantially. Therefore it is
important to use filters of the same quality and capacity when changing filters.
Standard filter class designations specify a filter's collection capacity. G4 de-
notes a basic filter and F5 – F7 denote fine filters; a higher number denotes a
higher collecting efficiency.
The filters are disposable and are intended for one time use. As filters become
clogged the air handling unit's capacity is reduced. The filters should therefore
be exchanged if the pressure drop across the filter exceeds a predetermined
final pressure drop. It is important to stop the unit prior to changing filters so
that dust will not be shaken free and be sucked into the unit. The filter sections
should therefore also be cleaned when changing the filters.
Inspection
Check the pressure drops across the filters. The pressure drops should be
measured with a manometer connected to the probes (measurement tappings).
The probes are connected on either side of the filters.
If the specified final pressure drop has not been reached, the filter should be
replaced.
Filter
Filter
