Wall Switch Failure

Here’s what happens to a really old wall switch:

Wall Switch - innards

Wall Switch – innards

A closeup of that broken contact:

Wall Switch - detail

Wall Switch – detail

This switch controlled an outlet, so I’m sure it’s hot-switched far too many vacuum cleaners, clothes irons, and suchlike over the last half century or so.

Our house is a bit fancier and originally had top-of-the-line mercury-wetted switches: the contacts sealed in the capsule don’t burn, but the springy supporting structures outside the capsule eventually wear out.

They’re still more reliable than X10 switches, though.


  1. #1 by Red County Pete on 2013-01-07 - 12:07

    Ours is a medium-nice manufactured home, built in late 1999. Some of it is well done, like the 2 x 6 framing and well-insulated spaces, while others are sad, like the 2 x 3 fingerjoint studs on non-loadbearing walls.

    The worst has been electrical bits, however. I already had a closet light switch fail. (Since we got the place in 2003, the load has been a 13W CF, but the plastic body of the switch failed.) Recently, I had the outlet for the TV/DVR fry. We have a Monster power conditioner plugged into it, with maybe 500-600 watts at a peak load. As best as I can tell, we had a corrosion spot and local heating and positive thermal feedback. The MPC tripped from low voltage with minor damage to the plug and molten plastic from the outlet (couldn’t locate the smell when it happened–found the problem a week or so later).

    I bought a contractor pack of receptacles and switches. Got good-grade outlets, but the higher grade switches were out of stock. However, even the standard grade Leviton switches are far better than the garbage used in the house–no manufacturer’s mark, or even country of origin. I swapped out the bad outlet and another one that got grout in it (oops, my goof there), but the rest seem to be OK. (Interior wall–no idea what happened, though the existing kitchen outlets are far better than the living room ones.) I’ll swap higher current outlets, like for the computer UPS, and will do all the light switches.

    The switches use the ‘stab in the back’ hookup, as do the lower grade outlets. The switches don’t even have screw terminals for the switched contacts. At least the ground uses a screw.

    • #2 by Ed on 2013-01-07 - 12:55

      The switches use the ‘stab in the back’ hookup

      There is no possible way you can get enough contact to match the 15 or 20 A wire rating, but there it is. And in a structure designed to be transported a significant distance over the road before being settled in place? That is just crazy, despite the fact that it’s all UL approved.

      At least we’re done with thinking aluminum house wiring made any sense at all…

  2. #3 by Frans on 2013-01-15 - 13:47

    I doubt any house in Europe has had such switchy looking switches since the 1960s or so. :P Ours look a little something like this (impression of internals).

    • #4 by Frans on 2013-01-15 - 13:50

      PS I’m aware your house is that old, but I’ve seen the exact same switches (albeit in off-white) in recent American buildings.

    • #5 by Ed on 2013-01-15 - 16:21

      That’s not a switch, that’s a door bumper!

      • #6 by Frans on 2013-01-15 - 18:00

        The 1960s house I grew up in had switches that looked more like this, by which I’m referring exclusively to the fact that they were push switches of similar size to the American pull switches. That particular example on the picture looks like the ugliest variety of that type imaginable.

        • #7 by Ed on 2013-01-15 - 21:10

          looks like the ugliest variety

          I vaguely remember seeing some of those when we did a bike tour in Germany, many years ago. Maybe I’m remembering something that I never saw, but they sure look familiar… and not something I would want on my wall, either.

  3. #8 by Mick on 2013-01-16 - 10:21

    ours (1950) had one switch in the hallway that was a push switch. The button was the same size as the traditional toggle, used the same switch plate, Press it to turn on, press it to turn off. It failed a couple years ago, I would like to know how many times that sucker cycled.

    • #9 by Ed on 2013-01-16 - 11:42

      Sometimes, stuff just wears out; I’d say more than half a century is Good Enough!