0 start-up instructions – AAF International PRU User Manual
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Step 3: Mark the tubes that are connected to the pressure gauges, to ensure that they
are returned to the correct locations later, and disconnect the tubes from the gauges.
Step 4: Remove the safety grille to access the fan and motor.
Fast, but limited access to the fan can be obtained from above the fan, as shown, with
the filters removed.
Secondary
Fan Access
Typical RU fan wheel
Direction of rotation
Fan blade
Fan wheel
If the fan wheel rotates in the wrong direction, the airflow will be
severely restricted and the system will not provide the proper airflow.
3.12.3 Installation: In order for the fan to be operated, some or all
of the following installation steps may be required:
3.12.3.1 On the standard product, the fan will be fully wired
internally, and the controls required to operate it will be installed.
Under some circumstances, the installer may need to provide,
install, and wire a properly sized motor starter. See the AAF wiring
diagram supplied on the order for details. In all cases, an
appropriate disconnect switch with fuses/circuit breakers shall be
provided. Normally these components will be supplied and installed
by others.
CAUTION: An electrical disconnect shall be incorporated into the
power wiring and mounted adjacent to the equipment, so that power
can be cut when required during start-up and maintenance. Normally,
the disconnect switch will be supplied and installed by others.
3.12.3.2: Installation of Power Wiring to the Fan Motor: See the
AAF wiring diagram supplied on the order for details.
3.12.3.3: Provision, installation, and wiring of any special controls,
and interconnecting wiring to associated equipment such as
dampers, airflow monitors, chemical sensors, etc.
For guidelines on fan selection see paragraph 9.1
4.0 Start-up Instructions
Check the rotation of the fan wheel to ensure that the fan motor is
wired correctly. The centrifugal fans typically supplied with the RU
feature fan wheels with backward curved blades. It is critical that the
blades rotate in the direction shown.