Some Steam Engineer humor, we have a condensate return tank at work, water from it is pumped into the Deaerator, then pumped into the boilers and out again as steam, where it's used and the remainder comes back to the return tank as condensate, it has a make-up valve that adds treated water to make up for losses, all very tidy.
Lately the modulating motor operating the make-up valve has been sticking so I ordered a new one, in the mean time the tank overflows occasionally, wasting water. One of my co-workers decided to have a high level alarm activated so we could manually cycle the valve. All well and good but the alarm comes back a "9.50 building alarm"
Shortly after he had it activated he writes in the log book that he kept getting some ghost alarm saying.. you guessed it "9.50 building alarm" He went on to say he checked the plant out and couldn't find anything, and by the way the condensate tank was high...
We just about fell over laughing when we saw that one.....

I guess you had to be there.