There are several factors to consider when deciding if repair or replacement is the best decision for a failing motor. Many facility managers believe that if the motor is larger than 15 horsepower, it is more cost-effective to repair it. Although this may be true when thinking about the initial cost, replacement with a motor that is energy-efficient makes much more sense in some situations.
A factor worth considering is if there will be degradation of a repaired motor’s efficiency, although motor repairs can improve efficiency a bit in some cases if done properly. There are field surveys that indicate that after a repair, motor efficiency may be reduced by two percent. Less efficiency means greater consumption of energy and an increased cost of operation. The effects of motor repair on efficiency can vary widely depending on the quality of the repair.
The replacement may be better than repair in some cases due to the fact that in many commercial applications, the purchase price of the motor is only a small fraction of the total cost of owning and operating the motor over its entire lifecycle. The motor’s purchase price amounts to approximately 5% of the cost during the motor’s lifecycle. However, electricity purchases make-up over 90% of the cost. In this case, it may make more sense to replace a failing motor with an efficiency unit that reduces the motor’s lifecycle costs by cutting energy costs.
Another factor to think about is that in some cases, motors may be too large for the function they perform and can be replaced by smaller and less costly motors that do the same job. Consider the motor’s entire lifecycle cost, the cost of saved energy, the ‘nameplate’ efficiency of the motor versus the actual efficiency, which may be significantly decreased after prior repairs, and the expected lifetime of the repaired motor versus a replacement motor.
Motor repair is generally preferable to replacing the motor when:
- The original motor is already a premium efficiency unit
- The original motor is only in operation for a few hours or days per year
- The original motor is custom-designed which makes a replacement difficult to locate
- The repair shop will guarantee that the repair will not downgrade the unit’s efficiency
Premco, Inc. is an engineering, design, service and sales company that is capable of repairing or replacing a full range of commercial motors and power generation equipment used in the largest commercial enterprises. We have 16,500 square feet of manufacturing space and over $5 million of machine tools including lathes, milling machines, surface grinders, ovens, welding machines, etc. We perform custom metal work for almost any client need including the manufacture of repair parts and accessories for discontinued and out-of-production machinery and our customer service team is second to none. Premco, Inc. is located at 11 Beechwood Avenue in New Rochelle, NY. Please call us at 914-380-7288 or email sales@premcoinc.net. We look forward to hearing from you.