Humming floor 3

[Skogsgurra]

I got a question about heated floors yesterday. It was a simple question: Why do floors hum?

The obvious answer, of course is that they do not know the Words. But this guy wasn't satisfied. "Must be harmonics" he said. "do you Think that a snubber could work?"

"OK, so it is a heated floor?" I asked.

It is a heated floor. With a thin resistive foil, no dimmer no thermostats. Just DOL, 230 V 50 Hz. The foil is covered with an insulating layer somewhere between 3 and 6 mm thick. And on top of that the floor as such. The foor hums so that people cannot sleep in the room where the floor is.

My take on this is that there is an electrostatic attraction between resistive foil and insulating layer (with an epsilon around 5). Force is voltage squared, so the dominating frequency should be 100 Hz. So far, Everything computes.

But this has never happened before. Anywhere. At least not in this guy's experience. And he works a lot with heated floors. Question: Do floors hum a lot? Or is this one a rare exception?

If they do hum - what do you do to silence them?



Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[Skogsgurra]

No. It isn't spooky, like that hum.

It is more monotone and at a constant low key. Technical, I would say.

And there is no loud noise at the end, like you can hear in that link of yours.

Also, it goes on and on. There's no starting or ending. It is like having Eternity visiting.

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[Ron]

FWIW....I agree with MikeHalloran....there's an air gap somewhere. If sandwiched in concrete, concrete shrinkage might have created such a gap. Inject epoxy, even sporadically...it might interrup the hum.

 

[dgallup]

Can you rectify the current to DC? Nobody will notice a 0 Hz hum.

Scanning back to the beginning, I see VE1BLL already suggested that several times. Still seems like the easiest solution to me other than adding a pink noise generator. Adding a little pink noise can be very helpful to sleep. I use a CPAP at night for medical reasons which makes a quite unobtrusive background noise. Nobody has ever complained about it yet with it on I have slept through nearby trains, massive lightning storms, even a night in a hotel where the EMS broke down the door to a room directly across the hall.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[Pudzrus]

By "Also, it goes on and on. There's no starting or ending", does this mean that the hum continues, even if the thermostat is satisfied (and so, the current is off)?