by Tom Hartman
There is no comprehensive body of analytical research on this topic but there is a great deal of operating experience and if we put that together with what we know contributes to mechanical and electrical equipment longevity, we can arrive at some conclusions that I think will pass the test of time when such analytics become available. Let’s start by looking at what factors affect the life of chiller room equipment – motors, pumps, compressors and fans.
For motors, failures are usually found to be a result of a winding or bearing failure. Other plant equipment failures are also often attributed to bearings but also primarily to gear trains, couplings and seals. For windings, the soft start characteristics and the continuous current limiting capacity of VFD operation makes overheating of the windings, which is a major cause of winding failure, nearly impossible. For bearings, gears and seals, the soft start is also a great benefit, but then operational wear and tear on these components can lead to failure over time. Such wear and tear is also reduced due to the brilliance behind the Optimum Loop operating regimen that ensures an even loading among all plant components. Yes, more components may be in operation, and each may operate longer hours. But the total work done by each plant component is less and that translates to less wear and tear on its contact parts. So while the jury is still not fully decided, all the information we have to date indicates that implementing the Optimum Loop will lead to longer equipment life in addition to the significant reduction in energy consumption.