Comment by LeonM | Hacker News Reader

Comment by LeonM | Hacker News Reader

There is another reason for the close door button: so that the manufacturer or service mechanic have something to blame.

In my building the elevators were brand new (less than a few months old) and were constantly out of order. The service mechanic was called in time after time, he would arrive, run diagnostics, find that nothing was wrong, then reset the control system and leave.

After the 10th time or so, the building manager demanded to have the entire system replaced under warranty. The manufacturer told us: there is nothing wrong with the lift, but you guys are constantly pressing the close door button, this breaks the lift! So obviously our abuse of the lift was not going to be covered under warranty.

We called their bluff we had the mechanic disable the close button. The lift still broke. A week later the entire control system was replaced (under warranty) and the lift has functioned normally ever since, though they never enabled the close door button again... :-(

The idea that pressing the door-close button would constitute "abuse" is laughable. If it's actually a self-destruct button by design, it should be locked out by default.

> constantly pressing the close door button, this breaks the lift

I'm not sure I understand the argument? Why does this break the elevator? Why would a built-in button crashing the elevator not be considered a fault?

> Why does this break the elevator?

It doesn't

> Why would a built-in button crashing the elevator not be considered a fault?

The manufacturer was trying to get out of a warranty claim, hoping the customer was naive enough to believe their story.

> The manufacturer was trying to get out of a warranty claim, hoping the customer was naive enough to believe their story

To be fair, I worked in the service industry for many years (as a controls technician), and I had many co-workers who intentionally set up long cons like this to stay busy. They would come up with equally outlandish reasons for why they needed to keep going back and upper management was mostly clueless as to how ridiculous they were.

Every pushbutton has a limited number of times you can press it. A close door button is usually pressed many times by impatient passengers. So it will wear out more quickly than any other button.

Humoring your ridiculous theory.

1) Buttons themselves have on the order of hundreds of thousands to millions of presses expected before any form of failure could begin to be expected. OPs story of a new lift failing would not even come close with a person standing there 24/7 mashing the button

2) A button failing would be just that: a failed button. Not an entirely failed control system. One would assume the button to be a Normally-Open activation, such that continuity in the circuit is achieved when the button press occurs so a failed button would look to be like a button that hasn't been presssed anyway. I'd be happy to be corrected on this, but a Normally Closed button is often only really used for safety sake where a break in the line, loss of voltage, or a button press are all treated equally by the control system.

I wonder what shitty manufacturer this was. A manufacturer this bad shouldn't be trusted with something as safety-critical as an elevator.

> you guys are constantly pressing the close door button, this breaks the lift

Even if it did, how can this be an excuse? It is obvious such a button is intended to be used for normal operation. The person answering that was probably clueless and/or desperate, any excuse would have worked better: the occasional overload, superficial and unrelated damage, kids jumping and mashing buttons, etc...

I guess such tactics may work on naive consumers, but I hope building managers know better than to fall for such bullshit. Case in point, yours didn't.

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