If the correct replacement part has a long lead time, a safe but suboptimal substitution can get production running. Production managers, understandably nervous about excess downtime, agree to the temporary solution. But temporary becomes permanent with attendant maintenance problems.

Suppose a 20-ton HVAC unit fails in June. Without it, three production lines can't run. But the replacement is backlogged until September. Division management says to install a 30-ton HVAC unit in its place. This upgrade requires half a day of electrical work from increased branch circuit requirements and a day of sheetmetal work to adapt the different roof curbings.

The landmine here is this mismatch will result in energy waste, cooling imbalances, unreliability, maintenance headaches, and reduced service life. Already, the unit's ice-laden coils have overloaded its motor several times.

In September's cool weather, these facts won't result in purchasing the 20-ton unit. In Part 4 of this series on avoiding landmines, we'll look at the solution.