Liebert DS User Manual

• Field lubrication is NOT required for the life of the bearing.
• Bearings are permanently sealed and self-lubricating and cannot be greased.

1. Disconnect power to unit.
2. Remove drive belts (see 12.2.2 - Belt Removal).
3. Inspect bearing for tightness of set screws and mounting bolts.
4. Rotate fan wheel by hand.
5. Listen for unusual noise and look for signs of unusual play.

1. To maximize performance and reliability of Liebert DS equipment, use only SealMaster Reduced 

Maintenance pillow block bearing with tapered lands race and double lock set screws. Contact 

local Emerson representative to order replacement bearings. 

2. Properly mount and align bearings on shaft. Tighten set-screws in proper sequence and to proper 

torque using a torque wrench in accordance with the manufacturer’s instructions.

Inspect motor at regular intervals. Keep motor clean and ventilation openings clear of dust, dirt and 

other debris.

• Motor comes pre-lubricated from factory and does NOT require initial lubrication. 
• Emerson recommends a 5-year lubrication interval for motor bearings that have grease fittings.
• Greases of different bases may not be compatible when mixed. 
• Contact specific motor manufacturer to determine type of grease to be used.

Check to see if wheel(s) are tightly mounted on fan shaft. Rotate wheel(s) and make sure they do not 

rub against fan housing. The wheel(s) should be periodically cleaned of dirt and debris.

Adjustment Nut

Motor Plate 

Adjustment Slot

Motor Base 

Carriage

Spring 

Housing

Minimum 1/2” 

(13mm) Gap