44
Airflow Balancing and Checking
High performance systems commonly have
complex air distribution and fan systems.
Unqualified personnel must not attempt to
adjust fan operation, or air circulation, as all
systems
have
unique
operations
characteristics. Professional air balance
specialists must be employed to establish
actual operating conditions, and to configure
the air delivery
system for optimal
performance.
Air Flow Monitoring
Some units include an air flow monitoring
device. Air flow can be measured either at the
outside air opening, supply fans and/or return
fans. Outside air uses a measuring grid and
the fans use a piezo ring on their inlets to
collect this information. A singular processor
located in the vestibule handles all of these
different readings.
Supply, Return, and Exhaust Backward
Curved Fans
RZ Series units are equipped with direct drive
backward curved fan assemblies that are
selected to deliver the air volume specified
according to unit size and job requirements.
This is either done with air volume bands in
the blower wheels or with VFDs. Field
airflow adjustment may be required at
startup.
Air volume bands for the wheels are sized
according to the unit’s air delivery
specifications and can also be ordered from
the factory for field installation. Wheels
come standard with a 10% air volume band,
as a safety factor, in case additional air
volume is required from the unit.
Airflow Adjustment
If reduced air volume is required an air
volume band or larger air volume band can
be installed within the blower wheel to
reduce the amount of air delivered by the
wheel.
If the unit is factory equipped with the air
volume band and additional air volume is
required, the band can be removed from the
wheel.
Use fan program in AAONEcat32
™
to
determine the new band size for the required
CFM and static pressure.
The following photos of a wheel are provided
for practical guidelines only in order to
identify the air band location in the wheel.
Actual field installation of the air band into
the wheel will require access into and through
the blower wheel venture, which may require
removal of the fan motor and wheel.
Air volume bands are made of aluminum,
sized and equipped with easy bend tabs that
are to be inserted into pre-punched slots
provided on the wheel. Once the band has
been inserted into the slots, it MUST BE
secured by bending the tabs over from the
back side of the wheel and also MUST BE
secured from the inside by connecting the
ends together with a pop-rivet in the holes
provided on the ends of the band.
Figure 20 - Air Volume Band
If the band is field installed, a hand held pop-
rivet tool is recommended for connecting the
Summary of Contents for RZ Series
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Page 31: ...31 Figure 4 4 Point Lift RZ Series Air Cooled Condenser Unit ...
Page 90: ...90 Gas Heater Operating Instructions ...
Page 108: ...108 Maintenance Log E Coated Coil ...
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