This may sound like a strange topic for discussion but I’m sure we are all aware of situations where previously reliable lifts start to experience problems and become a ‘rogue unit’. The term ‘rouge unit’ has been around for as long as I can remember but it is applied to lifts that are unreliable, suffer from erratic operational problems, intermittent faults and generally don’t perform very well. These lifts tend to develop a reputation of being a ‘bad lift’, and even if the problems are resolved the name sticks and is difficult to admonish.

The question here is why this happens, how problems manifest themselves and what are the consequences? An interesting point is that many problems can go unseen until a situation arises and the lift doesn’t operate as it should. A good example of this is load weighing settings. Incorrectly set, or suffering from ‘drift’ over time, it is not something visually apparent but can have a detrimental effect on the everyday operation of the lift, starting torque, anti-nuisance function, the load non-stop feature and car overload all depend on a correctly set load weighing device. As an aside, how often is load weighing calibration checked as part of the maintenance regime? Another example is the failure of a car fan. Not something most people would notice in everyday use; until a car full of people are stuck in a stifling confined space waiting to be released.