AFCI breaker tripping on lighting ckt after 7 yrs of working fine?

Status
Not open for further replies.
S

sw_ross

Senior Member
Location
NoDak
Situation,

Newer, higher-end home (7-years old), cutler-hammer panel, Lutron maestro type switches through-out (dimmers, 3-ways, 1-poles). Vaulted ceiling, open floor plan for kitchen and living room with fair amount of cans, pendants (over island), and ceiling fan (living room), as well as misc lighting for entry (inside and outside), pantry, hallways, etc.

I didn't wire up this home, but a reputable electrician did.

Everything has worked fine for the 7 years HO has lived in house. Now, the kitchen lighting ckt is tripping intermittently, and the liv rm lighting ckt tripped and won't reset (hold)! The AFCI breakers are in the 12 & 14 position (on top of each other) in the panel.

First troubleshooting attempt,

Since the living room AFCI wouldn't reset, but has worked fine up till now, and nothing else on that ckt has been changed I thought maybe the breaker had somehow "gone bad", so I used one of the other AFCI breakers in the panel to "test" the ckt. No-go, wouldn't hold on that breaker also! Just to confirm this test I used a brand new CH AFCI breaker off the truck, still wouldn't hold!

As an experiment at the panel, I put that lighting ckt on a regular (non-AFCI) breaker, which does hold! Went around to all the switch locations to play with the ckt and everything worked fine (except it's not AFCI protected!)!

The kitchen lighting ckt still trips intermittently (according to the HO), but I haven't been able to get it to trip when I play with the switches!

Request,

Before I start tearing switch boxes apart and try to map out the ckts, then gradually put the ckt bad together (in an attempt to find a bad switch or dimmer) I thought I'd ask for recommendations? It could take a lot of hours to do what I am thinking about doing, and I still might not find the issue!

Any suggestions are welcome!
Thanks in advance!
 
On the circuit that will not reset I would turn off all the switches and see if the breaker(AFCI) will hold and then try turning on the switches one by one to if it's just one fixtures or switch/dimmer that's bad. If that doesn't work I would trying to disconnect a part of the circuit and see if that helps. Anything you can do to isolate the problem the easier it will be to find.

These can be fun and take for hours, don't you just love these things ( AFCI breakers ).
 
Ha! I love this type of work (not!)! Unfortunately, I've done this type of service work too many times!

My previous experiences with AFCI issues were in houses that were wired up by the company I worked for at the time. So it was kind've a "warranty" scenario. Those were mostly middle of the road basic types of houses. This is a little fancier home with fancier switches and dimmers.

Interestingly, several of those homes had nuisance tripping with lighting ckts, not receptacle ckts! Those were Siemens panel & breakers. The company even ended up buying a Siemens AFCI diagnostic tool to use, but it didn't seem to be of much help!

Out of probably 4-5 homes that I had to go "find" the issue, it basically came down to tearing the ckt apart (maybe at the midpoint of the ckt), and then gradually, painstakingly re-assembling the ckt to find out which component of the ckt was causing the breaker to trip!

This issue re-enforced within the company to "map out" all the ckts on the plans which helped immensely with troubleshooting! That's why I'm not looking forward to troubleshooting this house, since I (or my company) didn't wire it up, and I don't have a wiring diagram for how the circuits are run!
 
Here is one path you can take: If the AFCI circuit breakers are tripping intermittently maybe look for a ground fault. Replace the AFCI with a GFCI circuit breaker (if it holds with everything off or in open position) then go through systematically and see if anything causes it to trip.

Also, as others have mentioned in the past look in to radio frequency interference.

Note:In 2008 I had issues with the Siemens AFCI combination CB's on LV lighting circuits as well.
 
I would try a GFCI so you know if you are looking for a ground fault or something that is tripping the arc detection circuit. A ground fault is easier to find.
 
Thanks!

Thanks!

Thanks for the suggestions!

I think there is a GFCI breaker currently in the panel that I can use for that test!

Also, I'll make sure all the switches are in the "off" position (not sure how I'll check that the 3-ways are off?)

Those fancy Lutron switches (dimmers, 3-ways, and 1-poles) must use a little power (since they have a LED display for brightness level), I don't think they have a neutral connection? Do they use the ground for the return path? And could that be a possibility?

image.jpg

I'm not looking forward to having to get up in this vaulted space to trouble shoot each of the R Cans! Maybe is is a bulb element that's going bad, but not burned out yet!? Maybe I'll talk them into converting over to LED and see what that does!?

Age wise it might make since that the elements in the bulbs are getting to the tail end of their life?
 
I think there is a GFCI breaker currently in the panel that I can use for that test!

Also, I'll make sure all the switches are in the "off" position (not sure how I'll check that the 3-ways are off?)

Those fancy Lutron switches (dimmers, 3-ways, and 1-poles) must use a little power (since they have a LED display for brightness level), I don't think they have a neutral connection? Do they use the ground for the return path? And could that be a possibility?

The Lutron Maestro Dimmers have a disconnect tab that you can pull out to keep current from the dimmer. I don't believe it total clears the dimmer though.
 
Knuckle Dragger said:
I think there is a GFCI breaker currently in the panel that I can use for that test!

Also, I'll make sure all the switches are in the "off" position (not sure how I'll check that the 3-ways are off?)
Click to expand...

That's why I suggested removing the bulbs and lamps.

Those fancy Lutron switches (dimmers, 3-ways, and 1-poles) must use a little power (since they have a LED display for brightness level), I don't think they have a neutral connection? Do they use the ground for the return path? And could that be a possibility?
Click to expand...

That certainly is a possibility.

The Lutron Maestro Dimmers have a disconnect tab that you can pull out to keep current from the dimmer. I don't believe it total clears the dimmer though.
Click to expand...

Not sure about that.
 
Also, I'll make sure all the switches are in the "off" position (not sure how I'll check that the 3-ways are off?)

If the light is off, then shouldn't the switch be off.

I had wired on house that everything was working fine. The painter was using one receptacle and then, the AFCI started tripping. Had all the switches off, turned them on, one at a time, one switch was tripping the circuit. Never figured out why, must had been ground making contact with something.

After 7 years of using receptacles on a circuit, perhaps the ground (being wiggled around a bit by movement of the receptacle) came into contact with a neutral or hot?
 
Knuckle Dragger said:
I think there is a GFCI breaker currently in the panel that I can use for that test!

Also, I'll make sure all the switches are in the "off" position (not sure how I'll check that the 3-ways are off?)

Those fancy Lutron switches (dimmers, 3-ways, and 1-poles) must use a little power (since they have a LED display for brightness level), I don't think they have a neutral connection? Do they use the ground for the return path? And could that be a possibility?

The Lutron Maestro Dimmers have a disconnect tab that you can pull out to keep current from the dimmer. I don't believe it total clears the dimmer though.
Click to expand...

Well, if anyone wired em half right, everything will be off with all switches down. :D (bad assumption but 90% of them are correct and its faster than pulling bulbs).

The skeptic in me wants to think the HO is fos, something has changed in that circuit to cause the breaker to trip. Look for new devices/fixtures first. Could be rodent/squirrel damage too; ask if they've heard any sounds up above, maybe a quick walk around the outside of the house, look for openings in the eaves and soffits.

I would definitely swap breakers with a GFCI as suggested to see if that holds.

I just thought about something... many electricians have wanted to put more LED lights on a circuit due to less draw... still limited by the fixtures... imagine if that got changed and you could run an entire house's lighting off of one breaker... and it would be AFCI... have fun troubleshooting that mess.

eta: Ive seen several Decora three-ways fail in weird ways, dunno if other newer brands are susceptible to those oddball failures, but a bad switch could be the culprit. I'd check those that get used the most; 7 years is awfully soon for a switch failure.
 
sw_ross said:
Situation,

Newer, higher-end home (7-years old), cutler-hammer panel, Lutron maestro type switches through-out (dimmers, 3-ways, 1-poles). Vaulted ceiling, open floor plan for kitchen and living room with fair amount of cans, pendants (over island), and ceiling fan (living room), as well as misc lighting for entry (inside and outside), pantry, hallways, etc.

I didn't wire up this home, but a reputable electrician did.

Everything has worked fine for the 7 years HO has lived in house. Now, the kitchen lighting ckt is tripping intermittently, and the liv rm lighting ckt tripped and won't reset (hold)! The AFCI breakers are in the 12 & 14 position (on top of each other) in the panel.

First troubleshooting attempt,

Since the living room AFCI wouldn't reset, but has worked fine up till now, and nothing else on that ckt has been changed I thought maybe the breaker had somehow "gone bad", so I used one of the other AFCI breakers in the panel to "test" the ckt. No-go, wouldn't hold on that breaker also! Just to confirm this test I used a brand new CH AFCI breaker off the truck, still wouldn't hold!

As an experiment at the panel, I put that lighting ckt on a regular (non-AFCI) breaker, which does hold! Went around to all the switch locations to play with the ckt and everything worked fine (except it's not AFCI protected!)!

The kitchen lighting ckt still trips intermittently (according to the HO), but I haven't been able to get it to trip when I play with the switches!

Request,

Before I start tearing switch boxes apart and try to map out the ckts, then gradually put the ckt bad together (in an attempt to find a bad switch or dimmer) I thought I'd ask for recommendations? It could take a lot of hours to do what I am thinking about doing, and I still might not find the issue!

Any suggestions are welcome!
Thanks in advance!
Click to expand...

A few months ago we had a lighting circuit tripping intermittently. We narrowed down to a 3-way switch that was causing the problem. You may want to check the switches. Also, have they plugged anything new in? Changed any lamps? Put any nails in the walls?
 
Yeah, when I was talking about having the 3-ways in the "off" position, but not knowing if they're actually in the off position, I was talking about the ckt that the breaker won't hold! I will remove the lamps/bulbs in that ckt to see if the breaker will hold.

I know when I install 3-ways I set it up so if the 2 3-ways are in the down position the light is off! S.O.P.!
 
Before taking all the lamps out, try pulling the air gap device out on the switch ( little thumb nail pull out on the bottom of switch) this should take everything from the switch to the fixture out of the picture at least the switch leg portion.

Take an educated guess as to where the home run might start and take apart there, see if breaker holds and then work your way down stream
 
Lutron maestro switches ( at least the homeworks and ra 2 version) have a air gap pull out to break the load, and I think the op said they were maestro
 
Status
Not open for further replies.
Top