Greenheck Downblast Centrifugal Roof Exhaust GB-240

Adjust belt tension after the first 24-48 hours of operation

Adjust and tighten belt as necessary

Loosen the setscrew holding the bushing and shaft key in place, if present.

Loosen and remove the socket head cap screws fastening the bushing to the hub.

Select the mounting type for socket head cap screws installation

Tighten the socket head cap screws an eighth of a turn at a time, alternating between them until the hub comes loose from the bushing.

Clean all surfaces of hub and bushing to remove any oil or residue. Do not use lubricant.

Select the mounting type for sliding components onto the fan shaft

Use the keyway setscrew to hold the shaft key and bushing in place, if present. Do not overtighten.

Disconnect and secure all electrical power to the fan.

Ensure the unit is non-functional by removing fuses and locking off the disconnect.

Are grease fittings provided on the motor?

Does the motor temperature exceed 104ºF (40ºC)?

Enter the current running time of the motor in hours.

Replace the grease if the running time exceeds 2000 hours and motor temperature is within limits.

Disconnect all electrical power to the fan and secure to the 'off' position.

Ensure the unit is made non-functional by removing fuses and locking off the disconnect.

Check for oil and dust accumulation on the wheel and housing.

Clean the wheel evenly to prevent imbalance and vibration.

Clean the housing to ensure smooth operation.

Is the wheel balanced after cleaning?

Check belts for wear and tightness.

Verify belt type matches the original unit specification.

Loosen the tensioning device to allow belt removal by hand.

Install new belts and adjust as per 'Pre‑Starting Checks' guidelines.

Check pulley setscrews for tightness.

Ensure proper keys are in keyways.