A couple months ago, I had a Lasko box fan that shorted out. It had been rattling for months, and toward the end it became a lot quieter. The fan was old. There was a weird smell and I saw a spark inside the fan. I immediately unplugged it and part of the plug broke off inside the outlet. A couple people told me that there couldn't have been a fire because the fan and outlet both have something that will cut the circuit before there is a fire. I have another Lasko fan that I have been using since, also old. I have been fearing that it may also be on its way out but I want to use it as long as possible. Today I noticed a slight rattling, and the motor was hot. I cleaned some dust off the motor and after a while, it was rattling a little but the motor wasn't hot. How do I know when to stop using the fan and buy a new one so that I do not run it to the point of shorting out like the last one? I would like to use it as long as possible but do not want to run the risk of that happening again, and I am still afraid of a potential fire, though not a lot. What is the sure sign I should junk it before something dangerous or inconvenient happens? I don't want to throw it away if it still has life left in it but do not want to force it to run if it's life is already spent either.