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OPERATION OF FAN:

After installing the fan per these instructions and the instructions of the

manufacturers, make final safety checks to prevent injury to personnel

or damage to the equipment.

Always block rotating parts to prevent

windmilling while inspecting the fan.

1. Lock power source in “OFF” position.

2. Check bearings for alignment and proper lubrication, with wheel and

inside of the housing clean and free of debris.

3. Check wheel position for proper clearance and rotation. Unblock

rotating parts and turn wheel by hand to insure that it rotates freely.

4. Check sheave set screws or bushings and wheel set screws for tight-

ness. If fan is a HEAT FAN, check to see that the shaft cooling wheel

bolts are tight. Check foundation bolts. Secure safety guards and

access doors.

5. If fan is designed for low density (such as high temp), make sure

overload of fan motor is avoided if fan is run with standard air.

6. Start fan and allow unit to reach full speed, then shut down. During

this short period, check for rotation, excessive vibration, any unusual

noise, or overheating of the motor. Check the motor amps drawn

against the nameplate rating. A plate over the fan inlet will limit the

horsepower drawn during a test run with limited ductwork.

7. After the trial run lock the power “OFF”.

8. Recheck for tightness of hold-down bolts, wheel set screws and keys,

and retighten if necessary. Recheck after eight and twenty-four hours

of operation.

9. The run-in period should be at least eight hours. Check bearings a

minimum of once each hour during this period. Overgreasing may

cause bearings to heat up. There need be no concern if the bare hand

can be held on the bearings briefly. Bearings will vent extra grease

and cool down after start-up. Recheck torque of all bearing set

screws after eight and twenty-four hours of operation to insure levels

are maintained per the bearing manufacturer’s recommended levels.

Take vibration readings at the bearings, or the motor bearings if

the fan wheel is mounted directly on the motor shaft. Adhere to these

limits. Velocity limits in inches/second – Normal: 0.15; Alarm: 0.22;

Shutdown: 0.50. These values are peak velocity values, filter-in, at

the fan rotational speed.

MAINTENANCE:

To insure long life and trouble-free service, frequently check all bearing

lubrication. See the bearing manufacturer’s instructions packed with the

fan. Should excessive vibration develop, check the following possibilities:

1. Build-up of dirt or foreign material on the wheel.

2. Loose bolts on bearings, housings, foundation and drive.

3. V-belt drive improperly aligned. Belts must have proper tension,

sheaves must be balanced.

4. Check wheel set screws or bushing cap screws.

5. Foreign matter may have entered fan causing damage to wheel, shaft

or bearings.

6. Vibration may be coming from a source other than the fan. Stop the fan

and determine if the vibration still exists. Disconnect the driver from the

fan and operate it by itself to determine if it produces vibration.

7. Improper clearance between the wheel and the inlet cone.

A preventive maintenance schedule is a necessity for extending fan life.

Establish a lubrication schedule based on time periods suggested in

lubrication instructions and by motor and bearing manufacturers.

After approximately one (1) month of operation, all base, hub bearing,

pedestal, etc. bolts should be checked.

Potentially damaging conditions are often signaled in advance by

change in vibration and sound. A simple, regular audio-visual inspection

of fan operation leads to correction of the condition before expensive

damage occurs. Vibration levels should be checked by an approved

technician using electronic balancing equipment.

If air handled by the fan contains corrosive, erosive or sticky materials,

fan should be shut down regularly for inspection, cleaning and recondi-

tioning of interior parts.

If the fan is to remain idle for an extended period, fill bearing with grease.

Protect motor and exposed surfaces. Follow the motor manufacturer’s

recommendations for storage and rotate the shaft by hand several revo-

lutions each month.

Mechanical Integrity:

Certain operating conditions reduce the built-in

strength in the fan impeller and may cause unsafe operation. It is the

user’s responsibility to inspect for these conditions as frequently as

necessary and make corrections as required. Failure to comply with the

following limits voids the Chicago Blower Corporation warranty.

Maximum Safe Speed and Temperature:

Operation exceeding maxi-

mum safe RPM and temperature even for a short time causes over-

stressing or fatigue cracking of the impeller resulting in unsafe condition.

Maximum safe speed and maximum safe temperature are shown on fan

assembly drawings, catalogs or order acknowledgement.

Warranty:

The warranty on Chicago Blower fans is our standard warranty. The warranty on the motor is that extended by the motor manufacturer.