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That weird hum in a 90s Dover traction machine turned out to be a simple fix
Got called out for a constant low hum in a bank of three elevators in a 20 story office building. The super said it had been there for years and two other companies couldn't find it. I isolated it to the machine room, pulled the main line fuses one by one, and the hum stopped when I pulled the one for the car top fan circuit. The 120V transformer for that circuit was mounted directly to the steel machine bed, vibrating it. I put a half inch of rubber gasket material under the mounting feet. Hum gone in ten minutes. Anyone else run into a vibration noise that was way simpler than it sounded?
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caseythompson15d ago
That "vibration noise way simpler than it sounded" reminds me of a buddy's call. He spent an hour in a penthouse lobby chasing a buzz everyone swore was in the walls. It was a loose faceplate on the hall exit sign, rattling from the HVAC draft. Tightened two screws and the noise stopped.
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shanef3415d ago
That exit sign story is a classic.
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xena_bailey1815d ago
Oh man, that's so real. I've found those mystery buzzes are almost always something dumb and obvious once you spot it. A trick that works for me is to use a mechanic's stethoscope or even just a long screwdriver, press it against stuff, and listen. The loose part will sound way louder. Saves so much time poking around.
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