View Full Version : GFI trips intermittently
JimfromSTL
Jun 7, 2010, 04:22 PM
My daughter has a gfi that controls two receptacles and a light switch in her bathroom. She has owned the house for about a year and had no problems with the GFI. However over the last two months, the GFI has started to trip intermittently. She told me it does not rip when being used - just some mornings it has tripped. It generally works once reset (although she has said that sometimes she has to a different receptable and then reset it when she got home from work)... I presume something is tripping it... and its possible there is something down stream from the GFI (it is a very old house that was rewired in the 80s) but so far she can't find anything that is also "not working" when the GFI is tripped.
My first and most important question is whether this represents any urgent safety or fire issue... and second question is presuming that nothing is downstream and the wiring on the receptacles are properly done - what would trip a GFI when (supposedly) not in use? I will be visiting her in a few weeks and will take a look at it (she called the other night with my to-do list for my visit and this was on it).
Any guidance would be much appreciated.
Jim
Missouri Bound
Jun 7, 2010, 05:16 PM
Bring another GFCI with you. Sometimes they just go bad. Check all connections when you replace it. Examine all the receptacles downstreem for loose connections as well.
KISS
Jun 7, 2010, 11:24 PM
I'll just add a weird cause. Suppose bugs made a nest in an outlet? Add moisture and you get some amount of intermittant tripping.
Identify all outlets that go out with this GFCI. You can take it out and see if there are connections downstream. You could then possibly trace along the walls with a non-contact voltage detector to find other outlets and examine each individually or just replace it and hope for the best.
Stratmando
Jun 8, 2010, 06:16 AM
I would remove the Light from the GFI. Power to the light switch and the lights neutral would need to be on the Line side.
A GFI will trip if the hot and neutral on the line side are equal.
Bugs and moisture, lizzards can do this.
JimfromSTL
Jun 8, 2010, 06:26 AM
Lizzards?
Stratmando
Jun 8, 2010, 06:29 AM
I'm in South Florida, and you will often find a lizzard across a couple of connections. You can't make this stuff up.
Shoot, we just had a Gator removed from one of the schools hallways.
JimfromSTL
Jun 8, 2010, 06:32 AM
Thanks to everyone for the info. Seems to be a solvable problem... although if it is lizzards I will be truly impressed!
roryrobie
Jun 8, 2010, 09:37 AM
Jim I would think in a housae that old that an outside recp may be down stream u might also check this alonge what the others have said
JimfromSTL
Jun 8, 2010, 09:48 AM
Thanks... I will look. The house is from 1887 but the wiring - which I have found to be dubious (in particular grounds not securely fastened - or not fastened at all) in places - seeming was done in a rehab in the 1980's (and I actually suspect the bathroom was updated subsequently - although no records)...
JimfromSTL
Jun 9, 2010, 12:38 PM
Hey I got some new info... it seems the gfi went from working as expected, to working intermmittently to now it works only if you plug something into the lower receptacle outlet of the gfi, then it works, but otherwise it does not work... that sounds like a lose wiring of some sort to me... but I guess it could be a gfi going bad... or something else?
Stratmando
Jun 9, 2010, 02:20 PM
Leave the light off and see if it trips.
KISS
Jun 9, 2010, 02:23 PM
I've seen hundreds of receptcles go bad in that fashion. A particular design from one manufacturer.
JimfromSTL
Jun 9, 2010, 03:03 PM
Thanks...
Stratmando
Jun 9, 2010, 04:50 PM
I'm taking it you feel it is the GFI, It is only rare that a switched leg is barely making contact with a neutral or a ground causing a GFI to trip. It does happen and can easily be proved out.
If half of your GFI is separated as you describe, it is bad.
JimfromSTL
Jun 10, 2010, 05:31 AM
I am thinking it's the gfi or a loose connection of some sort given how the problem has evovled and there is no obvious "event". The latest news even makes me think it is less about the GFI tripping and more about the strange behavior of needing to plug something into to the bottom outlet in the receptable to make the "gfi protected" circuit link down from it. I will see if I can move the light switch to before the gfi as that seems to be a general recommendation... just don't know where or how the power is routed to the various outlets yet.