
14
Air flow drops in the filters, due to dirt
TD
A 09
TD
A 15
TD
A 21
TD
A 27
TD
A 35
1
3
2
1 = CLEAN FILTER
2 = FILTER 25% CLOGGED
3 = FILTER 50% CLOGGED
The charts to determine the air flow
drops with different filter dirt levels
are shown below. From the left-hand
chart (showing the air flow rate -
m³/h - on the x co-ordinate), locate
the flow rate in question then go up
until you intersect the straight line
corresponding to the unit size. At
this point, by tracing a straight line
parallel to the x co-ordinate axis,
intersect one of the three curves on
the right-hand chart, each showing
the degree of obstruction of the
filter, as below:
curve 1: clean filter
curve 2: filter 25% clogged
curve 3: filter 50% clogged
To determine the corresponding
value of the filter pressure drop,
trace a straight line as far as the x
co-ordinate axis.
Air conditioning unit -
TDA range
Selection, installation, use and maintenance manual