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lsst_gw

recessed can light not working-please advise

lsst
11 years ago

You guys have been great in helping me with all my electrical problems over the years and I appreciate it!

I have a new problem.

I have a non-insulated 6" recessed can light that was installed by an electrician 8 years ago in our new build.

The can is not accessible from the attic. It is between floors and has no insulation around it.

It suddenly quit working. I never exceeded the wattage and it had a 45 watt bulb in it when it quit working. It is a single toggle switch running just to this one light.

Troubleshooting I have:

1. Changed the light bulb more than once

2.Changed the toggle switch

3. Checked voltage - both the switch and socket are receiving current

4. Pulled on the metal tab in the socket to get a better connection between socket and bulb.

5. looked at wiring above socket (only what was visible)

Some extra facts that may or may not affect the recessed can light.

During the build we had a major leak and water poured in the wall through the can light and onto the floor. After the light dried out, it worked so nothing was done about it.

After 8 years could the water leak have caused corrosion to the point something is wrong?

The whole fixture- socket and inside of can is sprayed with

paint primer. The painters did not cover the cans when spraying. Could this have made the light malfunction early?

I think the manufacturer may have been HALO but I am not sure as the whole can is sprayed with white primer.I recall HALO being mentioned during the build

The double gang box also has a three way light to a chandelier. The chandelier light is on a dimmer. Could the heat of the dimmer cause problems with the wiring since both toggles are next to each other in the same box.

All other lights ( chandelier etc.) are working fine.

I have not pulled all the wires out of the gang box and checked for over heating etc. This is my next step. Since the switch and socket are showing voltage, I assume the wiring from the switch to the socket is fine. Is this a wrong assumption?

Could the thermocouple have gone bad? If so would the socket still show a positive for voltage?

If the thermocouple is bad does that require installing a whole new fixture?

Thanks in advance!

Comments (31)

  • elltwo
    11 years ago

    Did you measure the voltage to ground or the screw shell?

    You may have lost contact with the grounded conductor (sometimes called the neutral).

  • lsst
    Original Author
    11 years ago

    Thanks for the reply.
    On the fixture, I used a voltage detector at the screw shell.
    The screw shell is almost entirely covered in sprayed paint primer. Can the paint prevent a good connection between the bulb and screw shell?

  • David
    11 years ago

    Depending on the thickness of the paint, it could dramatically increase the resistance of the circuit.

    I would start at the recessed can first.

  • brickeyee
    11 years ago

    The can can be removed from below to access the junction box to the branch circuit wiring.

    The water may well have caused corrosion on and in the lamp and its electrical connections.

  • lsst
    Original Author
    11 years ago

    Thanks for the replies! Before I read the last two replies,
    I disconnected and reconnected the wires in the double gang box and checked everything out. All the wires looked o.k.

    What I found strange though was even with the switch off, I still showed voltage at the screw shell. Is that normal?

    How do I disconnect the fixture from below? I really do not want to install another can but would prefer a regular fixture. If a regular fixture will not work, I would look for an insulated can.

    Thanks!

  • bus_driver
    11 years ago

    Modern digital testers draw so little current from the tested conductors that insignificant induced voltages may register on the testers. Older analog testers used more current and would drain off the induced voltage while not registering it's presence. I use two 15 watt incandescent "bulbs" in series as my main tester.

  • elltwo
    11 years ago

    Does the voltage detector look like a penlight or does it have two cables about a foot long with metal tips on the ends of the cables?

  • lsst
    Original Author
    11 years ago

    elltwo, it looks like a pen light and just detects voltage-not measures it.
    I do have a voltage meter with the separate metal tips that measures voltage.

  • elltwo
    11 years ago

    Try measuring the voltage by touching the screw shell and the tab in the bottom of the socket (both at the same time, but without the tips touching each other), and then touching metal on the frame of the can and the tab in the socket and see if you have 120AC with both tests. Before you climb the stepladder, check your meter at a receptacle which you know is working.

  • lsst
    Original Author
    11 years ago

    elltwo,

    Thanks, I will do that when I get home from work.

  • lsst
    Original Author
    11 years ago

    O.K.,
    I tested a wall outlet and the reading was between 119 and 120.

    I tested the light fixture and got a zero reading and I tested the toggle switch and got a zero reading.

    The toggle switch is new and showed voltage yesterday. The switch next to it ( to a chandelier) is showing a reading of between 119 and 120.

    When I replaced the toggle switch I wired it exactly as it had been wired before so I have no clue as to why I do not have power to the toggle switch.

  • lsst
    Original Author
    11 years ago

    Another thing I noticed....

    When I checked out the wiring in the double gang box yesterday, the electrician 8 years ago had connected all the white wires together with a wing nut. The toggle switch had two black wires each one connected to the screws and and the ground wire to the ground screw.
    I expected to see a black wire to one screw and a white wire to the other.

    The toggle to the chandelier is done the same way and works.

  • lsst
    Original Author
    11 years ago

    In my previous post I meant wire nut not wing nut.
    The white wires and wire nut had black grease all in the connection. I wiped the grease off when I reconnected the wires.
    I thought the grease was only used in exterior applications.
    No other wires had grease.

  • brickeyee
    11 years ago

    "The toggle switch had two black wires each one connected to the screws and and the ground wire to the ground screw.
    I expected to see a black wire to one screw and a white wire to the other. "

    You need to get a copy if "Wiring Simplified" and learn how circuits are wired and operate.

    Outside of a switch loop using a white wire as a re-marked hot (look for a black mark or rurn of tape) white wires do not appear generally appear on simple snap switches.

    A black 'always on' hot wire on one terminal becomes a 'switched hot' on the other.

  • lsst
    Original Author
    11 years ago

    brickeyee,

    You are right. I have that book and need to read it.

    The electrician that originally wired our house made quite a few mistakes.

    My husband and I found a wonderful electrician through word of mouth that corrected all the mistakes we found at the time and for the next few years.

    Due to the economy, he moved back to his home state and I have yet to find a replacement electrician I trust.

    This is only one light that I do not use often so I really want to try to repair it myself.

    I have learned a lot from this forum and I appreciate all the help!

  • brickeyee
    11 years ago

    "Could the thermocouple have gone bad?"

    They are not as fancy as a thermocouple, just a simple bimetallic thermostat that open the circuit when it gets hotter than rated.

    they can corrode if the get wet.

    "double gang box"

    Is htis the switch box?

    You are going to have to get to thejunction box above or beside the light behind the ceiling.

    You can take the lights apart from below to gain access, you just have to figure out how.

    Usually the lowest ring of screws in the sides of the can are removed and the can assembly can be pushed up and than to the side to get to the junction box that is part of the lamp assembly.

    If you go to a big box store you can look at the units on display and see how they go together.

    Worse case purchase on, examine it at home, then return it.

  • elltwo
    11 years ago

    I wasn't clear with one of my earlier suggestions.

    I meant for you to check the voltage across the screw shell and tab with the switch "on" and "off". Since you already have the courage and smarts to take the switch out of the wall, test for voltage to ground on both black-wired screws (one at a time) with the switch on and off.

    If one of the screws is around 120 all the time and the other is around 0 half the time and equal to the other end half the time then the switch is good. If both ends are 0 all the time the the problem is that there is no power to the switch, and the reason may be where one of the black wires is bundled with one or more black wires in the double gang box. (The other black wire goes out to the fixture.)

    If the switch is good and the bundle of white wires has every wire with the same amount of copper exposed and under the correctly sized wire nut then the problem is either in the fixture or on the way to it ( a broken wire in the ceiling).

    What color is the wire nut and how wires are under it?
    Grease might indicate aluminum wiring.

  • lsst
    Original Author
    11 years ago

    elltwo,
    When I go home for lunch, I will check it out and let you know.

    When I checked out the wires in the switch box,I do know the wire nut was yellow and contained white wires.
    I wiped off some of the grease and changed out the wire nut for one without grease.

    Thanks

  • weedmeister
    11 years ago

    That 'grease' was probably an anti-oxidant. I don't generally use it. IIRC, folks use it when you mix copper and aluminum.

  • lsst
    Original Author
    11 years ago

    elltwo
    You stated: If both ends are 0 all the time the the problem is that there is no power to the switch, and the reason may be where one of the black wires is bundled with one or more black wires in the double gang box. (The other black wire goes out to the fixture.)
    That now appears to be a new problem possibly along with the fixture which was the original problem before I started messing with the wires in the switch box.

    I am reading zero for both black wires with the switch disconnected and with the breaker on and off.

    Apparently, I did not do something right when I reconnected the wires.

    I unscrewed each wire nut looked at the wires and placed the wire nut back on as I found it. The only wire nut I replaced was the one with the grease. I connected the same wires as before.

    What is bugging me most is the white spray primer on everything. I am having to use my nail to scrap the paint off to see the color of the wires. :(

    This is what I see in the box for the switch.
    I see 3 black wires with a yellow wire nut. One of the black wires comes from the wire nut and connects to the bottom screw on the right side of the Cooper brand toggle switch.

    I see a yellow wire nut connecting three white wires.
    ( This is the one that had the grease.)

    I see the green wire nut with the ground wire to attach to the ground screw.

    Finally, I see a black wire that comes straight from a wire sheath ( no wire nut) that is connected to the top right screw of the Cooper brand single toggle sweitch. ( The cheap 69 cent one from the big box store.

    I am now going to take off the wire nut on the black wires and check my connection.

    Thanks for all the help!!!

  • lsst
    Original Author
    11 years ago

    I just reconnected the three black wires- made a good connection but still reading 0.

  • lsst
    Original Author
    11 years ago

    I have looked at a wiring diagram and the switch box is wired correctly.

    Would the grease on the white neutral wires or my wiping it off the white wire connection have anything to do with the whole thing not working?

  • kurto
    11 years ago

    The "grease" wouldn't have anything to do with connection failing at the present time. My guess is that you have aluminum wiring, and the "grease" is NoAlox or some compound designed to keep the aluminum from galling. Removing that grease may reduce the life expectancy of the connection.

    If you don't have aluminum wiring or conduit, then the grease serves no purpose, and can be removed.

    Be aware that if you're trying to connect copper with aluminum wires there are special connectors that must be used instead of regular wire nuts.

  • lsst
    Original Author
    11 years ago

    Thanks kurto,

    All of the wiring is copper.

    I went through some of journal I kept while building and I was incorrect that the leak did not affect the light.

    I found a copy of an e-mail I sent to the builder stating that the light did not work. I now remember the electrician stopping by and fixing the problem fairly quickly.

    Could the grease have been graphite grease?

  • kurto
    11 years ago

    Without inspection, I really couldn't guess the type or reason for the grease. Graphite is a semiconductor, so it wouldn't be a good thing to introduce into electrical connections. Are your wires run through conduit? If so, it might just be left-over lubricant from the pulling operation. Again, it's not part of the electrical equation, so you need to look elsewhere for the root of the problem.

  • lsst
    Original Author
    11 years ago

    Thanks kurto,

    The wires are not run through conduit. This is just an interior recessed light in a small pass through area from the kitchen to the dining room.

  • elltwo
    11 years ago

    Hi lsst, sorry for the long delay. I have re-read your first post and now I wonder if there is any chance that the three-way for the chandelier was attached to the switch for the recessed? This type of mistake can exist for a long time if one end of the 3-way is hardly used, and the other end is almost always the operating end.

    Make sure that both ends of the 3-way switching operate the chandelier properly.

    I'm traveling again this weekend.

  • brickeyee
    11 years ago

    "Graphite is a semiconductor, so it wouldn't be a good thing to introduce into electrical connections."

    Graphite is a conductor, though not a very good one, and its conductivity can vary with the physical direction of current flow relative to any crystal boundaries present.

    Amorphous graphite has no real crystal structure and conducts the same in every direction.

    Grease may have been applied to try and displace any moisture from the flooding.

    I would almost bet on some corrosion in the wire nut spring, the light thermostat, or one of the lamps internal connections.

  • lsst
    Original Author
    11 years ago

    elltwo, I will check.

    I use both 3 way switches to the chandelier fairly regularly. I turn one on as I enter the DR through one entrance and turn it off at the other entrance as I leave. I will double check.

    I have no clue as to why I have lost power from the breaker to the switch box. The breaker box is less than 30 feet from this light switch- all interior.

    I truly appreciate all the replies.

  • lsst
    Original Author
    11 years ago

    I assumed that since both switches were in the same box that they were on the same breaker. Wrong.

    Last night I decided to give up on finding a solution at least for awhile. I only use this light about 4 times a year.

    In the middle of the night, I began to think what if it is on another breaker.

    We have 2 200 amp breaker boxes- one in an upper garage and one in the basement garage in the tool room.

    This morning, I checked the upper garage breaker box for the umpteenth time. Everything was turned on.

    I went to the 200 amp breaker box in the lower garage. A breaker was off. It was not labeled.

    I turned it on. I went upstairs and flipped the switch-the bulb came on and in a split second went out. I have no clue as to why the bulb went out so suddenly. I replaced the bulb with another 45 watt bulb and so far so good.

    All of the other first floor lights are on the upper garage breaker box. I had no reason to think that each switch in the same switch box was on a different breaker and a completely different breaker box.

    I think the initial positive reading I received with the voltage detector pen must have been a mistake as the voltmeter always registered 0.

    I have labeled the breaker as going to this can light.

    When the house was being built, the electrician forgot to label some of the breakers or forgot to label all the lights on a breaker. Several breakers were marked incorrectly. Over the past years, I would spend time turning breakers off to see what went where so I could label everything correctly.

    This one I probably forgot to turn back on as I do not use it often- thought the bulb had burned out and assumed the recessed can was on the same breaker as the chandelier.

    I access the upper breaker box 99 percent of the time and only need to turn off items in the lower breaker box maybe once a year.

    Thanks for all of your help!!