Daikin OAH 003G, Installation And Maintenance Manual

Page: 31 / 40

Daikin IM 777-7 31
Service and Maintenance
Front Load Filter Option
Front loaded filter options require that the filters be removed
and replaced from inside the unit.
To remove filters, rotate the wire clips. This releases both the
prefilter and the final filter. When installing clean filters, check
to verify the filters are fully seated in the frame (
Figure 40 ).
Figure 40: Frame and Filters with Holding Clips
Filter Gauges
Filter gauges indicate pressure drop for installed filters. If
prefilters are present, the gauge will indicate the pressure drop
for both pre- and final filters
Table 27 shows the typical filter pressure drop for clean filters
at rated air flow. The tables also show a final pressure drop for
front loaded filters.
Where a single filter gauge is used, the prefilters can be
removed to check the pressure drop of the final filters.
Figure 41: Filter Gauge
F l t e r
F r a m e
R o t a t e
W r e C l p
P r e f l t e r
F n a l
F l t e r
Table 27: Filter Pressure Drops
Bag filters—DriPak 2000
Efficiency 45% 65% 85% 95%
Rated velocity (fpm) 625 500 500 500
Initial pressure drop .20–.26 .21–30 .34–.48 .50–.70
Initial pressure drop 1.0 1.0 1.0 1.0
Cartridge filters—Varicel II MH, 4.25" deep
Efficiency 65% 85% 95% Efficiency
Rated velocity (fpm) 500 500 500 Rated velocity (fpm)
Initial pressure drop .43 .61 .70 Initial pressure drop
Final pressure drop 1.5 1.5 1.5 Final pressure drop
Cartridge filters—Varicel SH, 12" deep
Efficiency 70%
Rated velocity (fpm) 500
Initial pressure drop .39
Final pressure drop 1.2
Pleated panel filters
Type Perfect pleat AMAir 300 4"
Efficiency 30% 30%
Rated Velocity (fpm) 500 625
Initial Pressure Drop .36 .36
Final Pressure Drop 1.0 1.0
5700 filters
Efficiency N/A
Rated velocity (fpm) 500
Initial pressure drop .25
Final pressure drop 1.0
Pleated 62 Plus filters
Size 2" 4"
Efficiency 70% 70%
Initial pressure drop .42 .37
Final pressure drop 1.0 1.0