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Went to open the one of the  garage doors yesterday and found neither one had power. Checked the breaker box, nothing was tripped. Garage has two circuits, found one GFCI tripped. Unfortunately it's the circuit the 2 garage refrigerators are on. Luckily nothing defrosted. I reset it and it tripped a few minutes later. Everything was fine the day/night before.

This circuit has one outlet on a side wall, one outlet on the back wall, two outlets on the ceiling (one for each opener). I also discovered it has three outlets on the balcony and one on the back patio. All covered by a 15 amp breaker. The only things plugged in full time are the fridges and a fountain on a timer. All exterior outlets are in weather proof boxes. No rain recently, sprinklers do not hit the outlets.

I unplugged these items, replaced one outlet that I used my shop vac on the day before and installed a new GFCI. Tripped within a minute of resetting.

This morning I reset the GFCI and it stayed on about five minutes, then tripped. Did this three times with the same results. 

Any suggestions before I break down and call an electrician?

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Yikes!  My vote is for letting an electrician look at it.  The new GFI outlet that you installed that continues to trip should give him a good clue to your problem.  Luckly, my favorite contractors and favorite electrician or all fellow cowboy shooters.

 

Was the GFI that you originally found tripped part of one of the breakers in the breaker box?  I've had breakers in the box go bad and a couple of them were breakers that contained a built in GFI.  

 

It sounds like a lot of outlets for one breaker.

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GFCI breakers go bad - it's recommended to replace them every ten years. Household refrigerators/freezers are supposed to be on dedicated circuits, as peak draws can spike as high as 12-15 amps. A 20 amp breaker will take a 20 amp spike, but is designed to be de-rated 20% for continuous use - 16 amps.

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If there are no loads connected it indicates that you probably have failing wire insulation.  Most likely you have pinched cable somewhere or the knockout in box doesn't have proper cable clamp bushing.   You need a megger to isolate the cable segment with the fault; so, call an licensed electrician.  If it was my problem I would 1st open the 12A circuit breaker feeding the circuit.  Then I'd remove every receptacle in the circuit.  Then I'd check the insulation resistance to ground on the hot & neutral wires.  It should be at least 100K ohms.  Measure insulation resistance off the wires on the load side of the GFCI receptacle since this is where the ground fault is.  The GFCI receptacle has a current transformer where the hot & neutral circuit wires pass through.  The CT secondary current is the instantaneous sum of the hot & neutral current.  Therefore if there is current leaking to ground the instantaneous sum isn't Zero.  The GFCI's electronics compares the CT secondary current to the trip setpoint.  If the CT current exceeds the setpoint the relay in the GFCI is deenergize.   That is why the GFCI has to be energized to reset.  If the wiring met code when installed the only device in the circuit that uses the device's terminals to daisy chain the circuit is the GFCI.   At all the other boxes the device (receptacle) is connected via a pigtail.  To isolate the faulted cable segment you have to disconnect all the wire connections.  Then you megger each of the cable segments.  When you determine the segment with the fault pull the wires as far out of the boxes that it is in.  Inspect the cable where it enters the box.  Make sure the insulation isn't cut or crushed. 

An example of how an insulation failure due to pinched cable can take a long time is the was the fire in my next door neighbor's modular.  The fire occurred 10 years after the modular's installation.  The installer or 1st owner installed a ceiling fan at the marriage line.  The fan hanging eye's threads cut partially through the insulation.  Eventually the insulation totally failed an arcing fault occurred igniting the rafter supporting the fan.

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My recommendation:

 

If you don't know exactly what's wrong and have no experience don't fool with anything and call the electrician.

 

You won't believe how high labor rates get after explaining to a professional all the stuff you did that might make  their job harder.

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22 minutes ago, Marshal Mo Hare, SASS #45984 said:

Fridges have surge currents when they start can easily exceed 7.5 amps and two on the same circuit is just wrong.

A circuit breaker won't trip due to surge currents.  They have thermal (overcurrent) & instantaneous (magnetic) elements.  The overcurrent element has inverse time current trip characteristic.  It trips faster the greater the ratio between the trip rating and current.  The instantaneous element trips without delay if current exceeds its' trip setting.  This is typically 10 times the breaker rating.   GFCI's with plug-in refrigeration equipment can intermittently trip due to the surge current because the surge current is rich in harmonics which can cause the GFCI to trip.  With the current version of the electrical code there have been a sharp increase in GFCI nuisance tripping.  The current code requires GFCI protection on all 120 & 240 volt circuits 50 amperes and below.  That means that new & added construction residential HVAC compressor/condenser units are connected to feeders that have GFCI.  There have been many complaints of AC not working because the feeder GFCI trips.  This doesn't happen with all installs; however, it is such a common problem that the code writing authority, NFPA, has been asked to revisit the code change.  NFPA has declined to amend the code; because, the change was made in response to several children being electrocuted by close dryers.  The mfg's of residential HVAC units will have to test their products with all the available GFCI devices.  Note:  GFCI circuit breakers that have trips that will not trip due to current surges are much more expensive than other GFCI circuit breakers.

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Not saying I'm right or wrong here, but the two fridges have been plugged into this same outlet (GFCI) for three years and never once has it tripped.

I just used one of the outlets on this circuit the day before with my shop vac. I thought maybe when I unplugged the vac I somehow damaged the outlet, causing the problem.

As I stated above, the GFCI trips with no load. Funny thing is this morning I reset it and it stayed on for a good 5 minutes, before tripping. I wonder if it could be the actual 15amp breaker that runs this circuit?

47 minutes ago, Pat Riot, SASS #13748 said:

You won't believe how high labor rates get after explaining to a professional all the stuff you did that might make  their job harder.

And Pat, no Dremel tools have been involved, so far!

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Inspect each outlet box for insects or other critters taking up residence. Spider web is conductive. 
 

 If you don’t find anything then a professional is your best bet. 

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Regardless of how long your have been lucky . . . . That 15 Amp breaker is too small by about 15 Amps.  When the Electrician is there, ask about a brandy new 30 Amp breaker.

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3 minutes ago, Colorado Coffinmaker said:

Regardless of how long your have been lucky . . . . That 15 Amp breaker is too small by about 15 Amps.  When the Electrician is there, ask about a brandy new 30 Amp breaker.

Can't bump it up to 30a without replacing the wiring too - it's probably 12 or 14g now, and would have to be upgraded to at least 10g.

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3 hours ago, Wyatt Earp SASS#1628L said:

Went to open the one of the  garage doors yesterday and found neither one had power. Checked the breaker box, nothing was tripped. Garage has two circuits, found one GFCI tripped. Unfortunately it's the circuit the 2 garage refrigerators are on. Luckily nothing defrosted. I reset it and it tripped a few minutes later. Everything was fine the day/night before.

This circuit has one outlet on a side wall, one outlet on the back wall, two outlets on the ceiling (one for each opener). I also discovered it has three outlets on the balcony and one on the back patio. All covered by a 15 amp breaker. The only things plugged in full time are the fridges and a fountain on a timer. All exterior outlets are in weather proof boxes. No rain recently, sprinklers do not hit the outlets.

I unplugged these items, replaced one outlet that I used my shop vac on the day before and installed a new GFCI. Tripped within a minute of resetting.

This morning I reset the GFCI and it stayed on about five minutes, then tripped. Did this three times with the same results. 

Any suggestions before I break down and call an electrician?

I had the same problem for several years, finally it quit altogether. It was not the GCFI. When I called the electrician he went from that recepticle and checked if there were others that did not work, he found one behind a cabinet that only the top plugin worked. The bottom one had a wire that was loose. When he tightened it everything worked and didn't have to replace any thing.

kR

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A few years back, I would occasionally catch a whiff of something in my kitchen that smelled vaguely like rotten meat. One day, all the kitchen outlets quit. Whoever wired this old house wired ONE 110v outlet circuit in the kitchen, so if I ran two high-draw appliances at the same time, things got REALLY hot, but never tripped the 20a breaker. It's still only one circuit, but now I know better than to run the coffee maker, toaster, or microwave two at a time. No more stab connectors either. 

Outlet.jpg

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I would look harder at the fridges.

Use an extension lead and feed them from an outlet on another circuit to see if it makes a difference.

 Some older fridges used to have little heater elements in the door seal, butter compartment, condensate evaporator etc.

   These can fail and go down to earth thus tripping your GFCI thingy.

 Of course, I'm talking about Australian fridges, but I don't think that they are all that different.

 

Yes, I am an electrician

 

:ph34r:

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Both fridges are the same make and model and around ten years old. I now have them both plugged into the dedicated 15amp receptacle used for the whole house vacuum system, which we don't use anyway.  Using a 12ga drop cord taped down to the garage floor.

 

Today I went around checking all of the outlets on this circuit. Including the GFCI there are 7. I pulled them and checked the wiring. Nothing was loose or looked scraped. I also tightened down all outlet screws.

I just now realized I didn't check the two opener outlets in garage ceiling. Something to do tomorrow. 

 

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1 hour ago, Three Foot Johnson said:

Can't bump it up to 30a without replacing the wiring too - it's probably 12 or 14g now, and would have to be upgraded to at least 10g.

Likely only 14ga. As it's a 15A circuit. My diy start would be to start at the 15A breaker. It's been carrying a heavy load for a while. May even find the wire burnt or brittle right at the breaker.

NOTE: I AM NOT AN ELECTRICIAN

 

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6 minutes ago, Wyatt Earp SASS#1628L said:

Both fridges are the same make and model and around ten years old. I now have them both plugged into the dedicated 15amp receptacle used for the whole house vacuum system, which we don't use anyway.  Using a 12ga drop cord taped down to the garage floor.

 

 

Is that circuit protected by a gfci unit ? .... if not the fault may not show up.

Plug one fridge into a gfci protected circuit to see if it is the problem, ......... then test the other one the same way .........

In the mean time, is the original circuit functioning within normal parameters?

 

The gfci unit is there to protect you from faults. Protection of your house is secondary to it and is the domain of the circuit breaker.

 

An appliance with a fault to earth(ground) is a disaster waiting to happen if plugged into an outlet that does not have earth(ground) and sometimes the fault isn't strong enough to trip the breaker but is strong enough to kill you. Increasing the size of the breaker will just kill you deader.

 

Hope this helps.

:excl:

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The GFI is what is tripping. The 15amp breaker stays on.

 

Everything has been unplugged from all the outlets covered by that GFI and I visually inspected each today, checking for loose or scraped wires. Nothing that I could find. Something is tripping the GFI. Could the breaker itself be causing the fault?

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If a ground wire is touching a hot or neutral terminal (screw on a receptacle) on any of the receptacles on the circuit, the GFI will trip. It's probably an easy fix for an electrician on site but from 1,000 miles away, I'm just shooting in the dark.

 

Probably time to hire an electrician.

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I would run a 20A non-GFI dedicated circuit for each freezer.

 

Could be a failing GFCI outlet. Could also be a failing capacitor on one of the freezers, or a failing compressor.

 

Anyway, compressors don't always play well with GFIs on good days.

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I would say it is NOT PROBABLY time to call a certified electrician. IT IS DEFINITELY TIME TO CALL ONE! When we first moved into our house 33 years ago, we had a refrigerator and a freezer in the garage. After a while, the GFI breaker tripped.  Electrician removed the GFI breaker from that circuit and we have never had trouble with THAT one. HOWEVER, we had another GFI in a bathroom that eventually started tripping with no apparent reason why. Electrician replaced the breaker and we have not had trouble since. They do wear out.  Call the electrical dude. NOW! It is cheaper than having something serious cause a fire!

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GFCIs check for imbalances between the grounded (white/neutral), ungrounded (black/red/blue or “hot”) and grounding (bare or green) conductors. Particularly, the balances in “hot” to “neutral” are what are looked at, and significant imbalanced measurements in current are going to the wrong place and are considered a hazard. Tripping typically occurs in the 5-7 milliamp range.

But, like I said, I have generally found nuisance tripping neutral conductor related. I can think of only a handful of ground faults I have diagnosed that were specifically hot and neutral related. Each were moisture, insulation or contamination related. More often than not, hot to neutral, or ground, faults trip breakers or blow fuses due to the low resistance path to ground,

Neutrals and grounds inadvertently touching can divert enough current to the grounding conductor for an imbalance between hot and neutral currents to trip the GFCI, hence the name “ground fault”. Any imbalance sense going off of the neutral to ground is presumed to be enough of an electrical hazard by the device, and current flow is potentially going to a ground of a different potential than the electrical system, rendering branch circuit overload protection ineffective in clearing this type if ground fault and being a safeguard against it, as it relies on clearing ground faults that exceed the OCPD ( overcurrent protection device -a:breaker or fuse) rating through a combination of the breaker/fuse and a grounding conductor to deliver fault current back to the source ( ultimately the XO tap on the transformer). GFCI’s design are to clear ground faults not normally cleared as are low resistance ground faults as seen when say a hot wire hits a ground or neutral directly causing excessive high amperage ground faults. Examples of what what GFCIs are engineered to safeguard against are ground faults not going to the system grounding system; or through people to an equipment or earth ground;  or current from a grounded neutral to an equipment ground or earth ground or person; or any current flow to a high resistance/high impedance path   to ground, or earth ground, generally not detected by or protected against by standard OCPD’s.

 

I recently had a refirgerator that would trip the GFCI when it was plugged in. This was on an rv. He needed a new fridge. Id run one fridge at a time on the circuit to possibly isolate to either. Something as simple as a  faulty grounded capacitor can add a high impedance fault to the curcuit.

 

You could also isolate each fridge or the fountain by using a cord from a non gfci circuit/receptacle to a portable cord type gfci. Never series gfcis they nuisance trip each other.

 

I have also found, 4-5 times,  ground and arc faults in romex where the wire was nicked by the electrician with a razor knife when they cut the jacket off. Then years later, sometimes 25/30 years the plugging in and out causes just enough movement for a ground fault to present itself.
 

I have myself, not purposely, caused a poor connection by getting insulation under a screw and nuisance tripping on a GFCI occur. Even with screws gorilla tight.

 

Most interesting nuisance tripping for me was on a 480 volt 2000 amp gfci main breaker. Customer bought from a surplus, breaker refurb and testing place, a reputable business. It was available right away as opposed to 90-120 days new. Unit was brand new. Unit shipping was delayed weeks. It finally shipped but without the main. Seller stated the breaker tripped installed but bench tested fine. 
We installed it. Terminated the service entrance cables to the buss, below where the main bolted into place. As I was wiring it, I noticed a CT on the ground buss with a label with arrows and the words “current” flow. The ground buss connected to the neutral buss above (this is service rated equipment with the ground and neutral bonded at the service, as it should). The current flow arrows on the CT pointed in the direction of the neutral buss. The purpose of this CT is to give feedback to the GFCI main for leakage current  from the neutral to ground, or specifically in this case to an earth ground. The winding ratios, I don’t know what they are but I knew this wasn’t right and if backwards was only amplifying feedback to the GFCI, not reducing it. Called my bud up that 35-40 years ago worked at GE, now retired engineer and head of our state licensing board’s engineering division. Explained to him the problems I thought I had found and said “hey, I need to flip this CT over don’t I? Its backwards isn’t it?”He said  absolutely, flip it over and put the main back in, and he speculated that GE probably never figured it out at the factory and sold it surplus as is.
Well that fixed the problem there.

 

I know that was a long story, and you’re not running 2000 amps at 480, but I troubleshoot them all the same.

 

 

 

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A. Freezers should be on dedicated non-GFCI circuits. 

B. While not as critical, the garage door openers are also supposed to have their own dedicated circuit.

C. Split the circuit, as in pull the wires off the outlet halfway though the circuit. Reset the GFCI and see if it trips. No trip, the problem is in the circuit that isn't powered up. If it does trip, the problem is in the section still live. Keep splitting the remaining outlets until you isolate the problem. 

 

Just an FYI, if the electrician used the stab-in holes instead of the screws, that can cause issues.

If the ground and neutral are touching anywhere after the GFCI, that will cause a problem.

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2 hours ago, Dirty Dan Dawkins said:

 

GFCIs check for imbalances between the grounded (white/neutral), ungrounded (black/red/blue or “hot”) and grounding (bare or green) conductors. Particularly, the balances in “hot” to “neutral” are what are looked at, and significant imbalanced measurements in current are going to the wrong place and are considered a hazard. Tripping typically occurs in the 5-7 milliamp range.

But, like I said, I have generally found nuisance tripping neutral conductor related. I can think of only a handful of ground faults I have diagnosed that were specifically hot and neutral related. Each were moisture, insulation or contamination related. More often than not, hot to neutral, or ground, faults trip breakers or blow fuses due to the low resistance path to ground,

Neutrals and grounds inadvertently touching can divert enough current to the grounding conductor for an imbalance between hot and neutral currents to trip the GFCI, hence the name “ground fault”. Any imbalance sense going off of the neutral to ground is presumed to be enough of an electrical hazard by the device, and current flow is potentially going to a ground of a different potential than the electrical system, rendering branch circuit overload protection ineffective in clearing this type if ground fault and being a safeguard against it, as it relies on clearing ground faults that exceed the OCPD ( overcurrent protection device -a:breaker or fuse) rating through a combination of the breaker/fuse and a grounding conductor to deliver fault current back to the source ( ultimately the XO tap on the transformer). GFCI’s design are to clear ground faults not normally cleared as are low resistance ground faults as seen when say a hot wire hits a ground or neutral directly causing excessive high amperage ground faults. Examples of what what GFCIs are engineered to safeguard against are ground faults not going to the system grounding system; or through people to an equipment or earth ground;  or current from a grounded neutral to an equipment ground or earth ground or person; or any current flow to a high resistance/high impedance path   to ground, or earth ground, generally not detected by or protected against by standard OCPD’s.

 

I recently had a refirgerator that would trip the GFCI when it was plugged in. This was on an rv. He needed a new fridge. Id run one fridge at a time on the circuit to possibly isolate to either. Something as simple as a  faulty grounded capacitor can add a high impedance fault to the curcuit.

 

You could also isolate each fridge or the fountain by using a cord from a non gfci circuit/receptacle to a portable cord type gfci. Never series gfcis they nuisance trip each other.

 

I have also found, 4-5 times,  ground and arc faults in romex where the wire was nicked by the electrician with a razor knife when they cut the jacket off. Then years later, sometimes 25/30 years the plugging in and out causes just enough movement for a ground fault to present itself.
 

I have myself, not purposely, caused a poor connection by getting insulation under a screw and nuisance tripping on a GFCI occur. Even with screws gorilla tight.

 

Most interesting nuisance tripping for me was on a 480 volt 2000 amp gfci main breaker. Customer bought from a surplus, breaker refurb and testing place, a reputable business. It was available right away as opposed to 90-120 days new. Unit was brand new. Unit shipping was delayed weeks. It finally shipped but without the main. Seller stated the breaker tripped installed but bench tested fine. 
We installed it. Terminated the service entrance cables to the buss, below where the main bolted into place. As I was wiring it, I noticed a CT on the ground buss with a label with arrows and the words “current” flow. The ground buss connected to the neutral buss above (this is service rated equipment with the ground and neutral bonded at the service, as it should). The current flow arrows on the CT pointed in the direction of the neutral buss. The purpose of this CT is to give feedback to the GFCI main for leakage current  from the neutral to ground, or specifically in this case to an earth ground. The winding ratios, I don’t know what they are but I knew this wasn’t right and if backwards was only amplifying feedback to the GFCI, not reducing it. Called my bud up that 35-40 years ago worked at GE, now retired engineer and head of our state licensing board’s engineering division. Explained to him the problems I thought I had found and said “hey, I need to flip this CT over don’t I? Its backwards isn’t it?”He said  absolutely, flip it over and put the main back in, and he speculated that GE probably never figured it out at the factory and sold it surplus as is.
Well that fixed the problem there.

 

I know that was a long story, and you’re not running 2000 amps at 480, but I troubleshoot them all the same.

 

 

 

 

20 minutes ago, Cholla said:

A. Freezers should be on dedicated non-GFCI circuits. 

B. While not as critical, the garage door openers are also supposed to have their own dedicated circuit.

C. Split the circuit, as in pull the wires off the outlet halfway though the circuit. Reset the GFCI and see if it trips. No trip, the problem is in the circuit that isn't powered up. If it does trip, the problem is in the section still live. Keep splitting the remaining outlets until you isolate the problem. 

 

Just an FYI, if the electrician used the stab-in holes instead of the screws, that can cause issues.

If the ground and neutral are touching anywhere after the GFCI, that will cause a problem.

 

 I've been an electrician for over 40 years and I just noticed that you guys are talking a different language to me ...... as tradesmen :)

 .... a lot of your techniques, words, equipment and materials are very different from ours in Australia .... yet we essentially do the same job.

I just wish we spoke the same language .........   :blush:

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8 hours ago, Sedalia Dave said:

Inspect each outlet box for insects or other critters taking up residence. Spider web is conductive. 
 

 If you don’t find anything then a professional is your best bet. 

In particular, check for ant colonies.  Many ants are attracted to electrical circuits and are very good conductors while alive and insulators when dead.  Ants are a very common electrical circuit problem throughout most of the South and West states.  You can usually smell them as soon as you remove a box cover.  A chunk of pyrethrin strip in the side of each box will control them, but not remove their dead carcasses. 

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2 hours ago, Cholla said:

Just an FYI, if the electrician used the stab-in holes instead of the screws, that can cause issues.

If the ground and neutral are touching anywhere after the GFCI, that will cause a problem.

 

In my parents house, they used the stab in holes and the neutral became flaky and it burned out the electronics in 2 refrigerators in 2 years at over $1000 each. I was not around when that part of the house was wired and I have spent a lot of time on flaky problems in the wiring in the last 2 years.

 

If the GFI is tripping with nothing connected to it, then either it is bad or there is a wiring problem. A loose wire or if you have any conduit running underground, it can be holding water that has weakened the insulation on the wires. A meg ohm meter (preferably analog as I have gotten false readings on digital ones) is needed and somebody that has lots of experience using it.

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I hope this doesn't jinx it, but I reset the GFCI at 0900hrs and as of 1400hrs it is still holding. No load except for the light in the patio fan to monitor the circuit.

Going out of town for a few days. When I get back I'm going to be doing some rethinking of where things are plugged in, thanks to some of your suggestions. I may run a conduit from the dedicated vacuum circuit over to the refers so they will be on a breaker-only single use circuit.

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19 hours ago, Dusty Devil Dale said:

In particular, check for ant colonies.  Many ants are attracted to electrical circuits and are very good conductors while alive and insulators when dead.  Ants are a very common electrical circuit problem throughout most of the South and West states.  You can usually smell them as soon as you remove a box cover.  A chunk of pyrethrin strip in the side of each box will control them, but not remove their dead carcasses. 

My first thought was fire-ants but he is in Utah. I had to deal with fire-ants in Florida and Mississippi and they can cause an issue within an hour.

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