210.100-IOM (JUL 2021)
Page 42
AcuAir Hygienic Air Units
Maintenance
• Replace any damaged blades – clean operating parts.
• Inspect blade edge and side seal – replace as neces-
sary.
• Inspect pins, straps, bushings, and other similar com-
ponents, for wear and replace as required.
• Lubricate all moving part contact points and side seals.
• Inspect caulked joints between the damper frames and
the main structure – repair if the possibility of air or
water leakage exists.
Maintaining the filters
Visually inspect both pre-filters and final filters at regu
-
lar intervals and replace them when they appear dirty or
damaged. See
.
The process air stream static pressure drop across the
filters indicates the need to change the filters when com
-
pared to the manufacturer supplied final pressure drop
data. Generally these are 1 in. W.G.
for pre-filters, 1.5 in.
W.G
. for final filter, and 3.0 in.
W.G
for HEPA final filters.
Frick suggests changing filters out when the pressure
drop reaches 0.50 in. W.G
for pre-filters, 1.0 in.
W.G for
final filters, and 2.0 in.
W.G
. for HEPA filters. This ensures
the unit is operating at peak efficiency.
Finish and sealing
AcuAir
®
units use a food grade caulk for air and water
sealing on the interior and exterior. Inspect and repair the
sealing on the units as necessary.
NOTICE
It is important that food grade sealant be used when
repairing or replacing unit caulking.
Electrical conduit sealing
requirement
The AcuAir
®
hygienic unit has the potential to operate with
internal air humidity and external ambient temperatures
conducive to forming condensation. These factors make
it important that measures be taken to eliminate risk of
water and ice collecting where it has the potential to
cause damage or faulty operation. Before initial start-up
of the AcuAir
®
hygienic unit, make a thorough inspection
of all conduit openings and any compromised openings
resealed. Perform follow-up inspections as indicated on
the suggested in
Sources of water or ice
Water may enter the inside of the electrical conduit and
door switches by either of two methods: through un-
sealed conduit ends and flexible conduit pigtails before the
AcuAir
®
unit factory wiring being reconnected on site or by
moisture migrating into unsealed conduits that are open
to the inside the AcuAir
®
enclosure. Moisture that migrates
into an electrical conduit that is then exposed to outdoor
temperatures below the dew point of the air condenses
into water and drains to the lowest location possible. If
those outdoor temperatures are cold enough this water
may then turn into ice.
Remedy
In order to eliminate the collection of condensed water
inside electrical conduit, panels and instrumentation it is
very important that electrical conduit openings are ad-
equately sealed. Each sealed opening restricts the further
migration of moisture and the potential for water collec-
tion and damage.
The example in
highlights the important loca-
tions for sealing electrical conduit. This representation is
not to be considered all inclusive but rather a representa-
tion of the standard locations requiring sealing putty.
Plug Vertically Down
Conduit Openings At
All Door Switches
Plug All Junction Box
Conduit Openings
Typical (2) Boxes
Plug All Conduit
Wall Penetrations
(Many)
Plug All Smoke Detector
Enclosure Electrical
Conduit Openings
Plug All Gas Wrapper Panel
Conduit Openings
Plug All Control Panel
Conduit Openings
Plug All Starter / VFD Panel
Conduit Openings
Figure 49: Required putty locations
