McQuay Skyline OAC 003, Installation And Maintenance Manual

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28 McQuay IM 777-4
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.
Table 19 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
Coils
1
The coil must be clean to obtain maximum performance.
Check once a year under normal operating conditions
and, if dirty, brush or vacuum clean. Use a chemical coil
cleaner on multiple row coils. Read and follow the
chemical cleaner’s instructions as some cleaners may
contain harsh chemicals. Take care not to damage fins
while cleaning.
2
Drain pans in any air conditioning unit may have some
moisture. Algae, etc., can grow due to airborne spores
and bacteria. Periodic cleaning is necessary to prevent
this buildup from plugging the drain and causing the
drain pan to overflow. Also, keep the drain pans clean to
prevent the spread of disease. Cleaning should be
performed by qualified personnel.
F i l t e r
F r a m e
R o t a t e
W i r e C l i p s
P r e f i l t e r
F i n a l
F i l t e r
Table 19: 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