0 fan blade adjustment, 0 maintenance – Aerovent IM-401 User Manual

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Aerovent IM-401

2.3.1 Vibration Isolators

All fans are dynamically balanced to reduce vibration.

However, it is recommended that the fan be supported on

vibration isolators. Isolators should be selected for each instal-

lation in accordance with individual requirements. Concrete

inertia pads are generally not required with ATA and ATABD

fans.
2.4 DUCT CONNECTIONS

All fans should be aligned with the ductwork. A flexible

connection should be provided between the fan and duct to

prevent structure-borne noise from being transmitted to the

ductwork.

If the fan is to be attached directly to the duct without

a flexible connection, special care must be exercised to align

the fan and duct flanges so the fan is not subject to structural

loads from the ductwork. These loads could distort the fan

housing, causing the blades to hit or rub the case, or change

the blade tip to housing clearance and affect performance.
2.5 ELECTRICAL

All wiring should conform to local electrical codes and

the job specification. In NEMA standard MG-2, the phenom-

ena of transient torques is addressed. We advise that measures

be taken to protect your equipment from transient torque and

power interruptions.
2.5.1 Power Connection

The motor leads terminate in the conduit box. The

leads are factory connected for the voltage specified for the

job. Motor leads for wye-delta and part-winding starts are

not connected. Rigid conduit should be run from the motor

starter to the fan with a short section of flexible conduit at the

conduit box to allow for fan movement.

Wire size and motor overloads should be sized in

accordance with the fan nameplate electrical data. The conduit

box is located on the outside of the case on all direct driven

fans. On belt driven fans the motor is outside the fan case and

the connection will be made directly to the motor.
2.5.2 Motor Rotation

Check motor rotation by jogging the motor. The pro-

peller should rotate in the direction indicated by the rotation

arrow on the fan case. It is important that correct motor rota-

tion be established on ducted fans as the propeller will not be

visible after an inlet duct is installed. Reverse any two motor

leads to change direction of rotation of three-phase motors.
2.5.3 Final Check Before Putting

Fan Into Operation

1. Check for correct supply voltage and motor overloads.

2. Insure that all loose debris is removed from fan and ducts.

3. Check that the propeller is centered in the fan case and that

the blade tip clearance is not less than the minimum values

in Figure 2.

4. Hand rotate to assure free movement.

5. Bump the fan starter to check rotation.

6. Start the fan and verify that the vibration levels are

satisfactory.

7. Check the current draw. Do not exceed the full load amper-

age as specified on the nameplate.

3.0 FAN BLADE ADJUSTMENT

3.1 GENERAL

Models ATA and ATABD feature an adjustable pitch

propeller. The blade pitch has been factory set to meet the

airflow requirement of the job specification. If required, the

pitch may be changed to meet other airflow requirements on

the job site. Contact the factory for recommended new setting

and request an AXIPAL blade protractor.

NOTE: If the blade angle is reduced by more than five

(5) degrees from the value preset on delivery, the clearance

between the blades and the casing will be reduced. Check that

the blade tip clearance is not less than the minimum values in

Figure 2. If the blade angle is increased, check the tip clear-

ance for minimum clearance as the leading and trailing tips will

get closer to the fan casing.

4.0 MAINTENANCE

4.1 GENERAL

ATA and ATABD fans are a quality product designed

and manufactured for minimum maintenance and long operat-

ing life. They should provide years of trouble-free service if

the following maintenance procedures are followed.

There are no moving parts in the propeller assembly.

Therefore, routine maintenance is generally limited to motor

lubrication, bearing lubrication of the belt driven models and

belt replacement.
4.2 FAN BALANCE

The propeller assembly shall be statically and dynami-

cally balanced in accordance with ANSI/AMCA 204-96

"Balance Quality and Vibration Levels for Fans" to Fan

Application Category BV - 3, Balance Quality Grade G6.3. In

addition, direct drive fan propellers shall be balanced on the

motor shaft after final assembly in the fan casing, in the manu-

facturing facility, to the following peak velocity values, filter-in,

to the fan test speed:
Fan Application

Rigidly Mounted

Flexibly Mounted