Maintaining The Coil; Winterizing Water Coils; Removing And Replacing Components; Removing A Panel - McQuay Vision CA Series Installation And Maintenance Manual

Table 16: Filter pressure drops
Bag filters—DriPak 2000
Efficiency 45%
Rated velocity (fpm) 625
Initial pressure drop .20–.26 .21–30 .34–.48
Initial pressure drop 1.0
Cartridge filters—Varicel II MH, 4.25" deep
Efficiency 65%
Rated velocity (fpm) 500
Initial pressure drop .43
Final pressure drop 1.5
Cartridge filters—Varicel SH, 12" deep
Efficiency
Rated velocity (fpm)
Initial pressure drop
Final pressure drop
Pleated panel filters
Type
Efficiency
Rated Velocity (fpm)
Initial Pressure Drop
Final Pressure Drop
5700 filters
Efficiency N/A
Rated velocity (fpm) 500
Initial pressure drop .25
Final pressure drop 1.0
Pleated 62 Plus filters
Size 2"
Efficiency 70%
Initial pressure drop .42
Final pressure drop 1.0

Maintaining the Coil

To obtain maximum performance, the coil must be clean.
1
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.
CAUTION—Fin edges are sharp.
Drain pans in any air conditioning unit may have some
2
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.
Dirt and lint can clog the condensate drain, especially with
3
dirty filters. Inspect twice a year to help avoid overflow.
McQuay IM 672-3
65% 85% 95%
500 500 500
.50–.70
1.0 1.0 1.0
85% 95% Efficiency
500 500 Rated velocity (fpm)
.61 .70 Initial pressure drop
1.5 1.5 Final pressure drop
70%
500
.39
1.2
Perfect pleat AMAir 300 4"
30% 30%
500 625
.36 .36
1.0 1.0
4"
70%
.37
1.0

Winterizing Water Coils

Coils can freeze due to air stratification or failure of outdoor
air dampers and/or preheat controls. Drain all coils as
thoroughly as possible and then treat in the following manner.
• Fill each coil independently with an antifreeze solution
using a small circulating pump and again thoroughly drain.
• Check freezing point of antifreeze before proceeding to next
coil. Due to a small amount of water always remaining in
each coil, there is a diluting effect. The small amount of
antifreeze solution remaining in the coil must always be
sufficient enough to prevent freeze-up.
Note – Carefully read instructions for mixing antifreeze solution
used. Some products have a higher freezing point in their
natural state when mixed with water. McQuay
International is not responsible for the freezing of
coils.
Mold can cause personal injury. Clean drain pan regularly so
mold does not develop.
AVERTISSEMENT
La moisissure présente un danger respiratoire. Pour éviter la
moisissure, nettoyer régulièrement le bassin de drainage.

Removing and Replacing Components

Before removing any component, lock out and tag out all
power to the unit. Fans and belts can cause severe personal
injury or death.
AVERTISSEMENT
Avant d'enlever toute composante, couper et indiquer que
l'alimentation électrique à l'unité est coupée. Les ventilateurs
et les courroies peuvent entraîner des blessures personelles
graves ou même la mort.

Removing a Panel

To remove a side or top panel:
Remove the flat head fasteners located along the sides of
1
the panel.
Once all fasteners are removed, lift off the panel.
2

Removing a Frame Channel

Frame channels that run the length of the unit along the top can
be removed to allow access to both the side and top of the unit.
To remove the frame channel:
First remove any adjoining side and top panel(s).
1
Once the side panel is off, remove the flat head fasteners in
2
the corner of the frame channels.
Service and Maintenance
WARNING
WARNING
27