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This would be a good place for slolerner's friend to start, and doesn't require hiring an electrician. They can check the breaker panel to see if the breakers are all the right size. It might not be any more complicated than checking what they have with the breakers in the panel of a neighbour with a similar-sized unit.

I think it's nice that everyone is providing fire extinguisher and other "in case there's a fire" advice but it'd sure be better not to have the fire at all. It's probably especially so in a trailer where fire spreads quickly and chances of getting out aren't great.

Your closing paragraph is spot on, but I absolutely and strenuously disagree with "...doesn't require hiring an electrician"!!!

An amateur would have absolutely no idea what to look for, and the attempt could result in a potentially fatal sense of false security.

Edit: The only do-it-yourself step I'd advise is determining which outlets/lights are connected to which breaker and evaluating and balancing the load.

I'd agree if I had suggested something like "Pull the breakers and check to see what is wired to each." But I didn't. I suggested something that anyone can should certainly be able to do.


This doesn't involve anything more complex than opening the panel and marking down the breaker sizes on a piece of paper (they should be clearly stamped into the top of each breaker) and then comparing their list with a neighbour in a similar unit. If they see they have a bunch of 20 Amp breakers while their neighbour has mostly 15 Amp breakers, then they have sufficient suspicion to call an electrician.

Opening a panel and examining the breakers is very straightforward. I assume that, if a breaker tripped for whatever reason, they would not call an electrician to reset it.

Yes, this sounds reasonable. If the breakers kept getting tripped (for the right reason) and that is assuming they are breakers and not fuses, it would make sense that someone would get tired of it and some know-nothing at a hardware store would tell them (the previous owners) to put in a 20 instead of a 15 to "solve the problem." I have never witnessed a circuit going out in that place. That is a good starting point because if that is the problem, it's an easy answer.

This is so funny because everyone laughs at me when I use the analogy of a roll of toilet paper when trying to explain why the outer sectors on an HHD wear out first, why they get used the most. The roll moves slowly at the beginning when it has a lot of paper left but has to move really fast when you get near the end.

Then there is explaining how memory works: The stove and oven are RAM and the refrigerator is the drive. Someone else can come up with the household analogy of an SSD besides, maybe, mixing different colors of glitter together but knowing where each red piece is.

I still disagree...think it's a complete waste of time.

There's absolutely nothing slolerner's friend can learn next door that truly reflects on her own situation.

OK, they've got more lines, less lines, bigger breakers, smaller breakers…whatever. So what? Without knowing the complete history of both houses, right down to past and present power consumption, i.e. loads, and what kind of wires are in the walls, she'll have nothing more than incomplete info to give an electrician and no compelling reason to call one.

Here's what she needs to do, it's meaningful, and it's dead easy…

1. Easy math: amps x volts = watts, so a 15 amp line delivering 120 volts of electricity is rated for an 1800 watt load. (This doc says that long term sustained load should be no more than 80%...1440 watts, and I believe it's correct.)

2. Chart the house by turning off breakers/fuses (I've still got 'em!) one at a time and determining which line serves each and every outlet and light.

3. More easy math: Determine the total load on each line by adding up the rated wattage of each power drawing item it serves, and there should be the reason why stuff is getting hot. (This doc has general info on the rated wattage of items for which specific info is not readily available.)

Note that neither 1800 nor 1440 watts is set in stone; you can run a 2400 watt hair blower on a 15 amp line without any problems…but for only so long.

The bottom line is not really total load per se, but total sustained load, into which you've got to factor sudden load, like the refrigerator or air conditioner compressor kicking in.

Determining the total of long term load plus potential short term and sudden load on each existing line in her trailer should enable her to get a good idea of whether they're adequate.

There are even things that can be realistically inferred, rather than merely guessed at, e.g. a 20 amp line that gets hot under a relatively low, short term load may really be a 15 amp line that's been fitted with a 20 amp breaker to avoid trips (as in joemikeb's house).

I'll guess that pretty darn near 100% of homeowners haven't got the required skills or expertise to change a breaker...they'd have to call in an electrician and convince him to do the dumb deed for them, although replacing a 15 amp fuse with a 20 is certainly within the realm of possibility.

Under any circumstances, though, my method for testing is definitive, not guesswork.

Back in the day, it was not uncommon to "fix" a blown fuse by putting a copper penny (remember real copper pennies?) in the socket and screwing the blown fuze in to hold it in place. So upsizing a breaker follows in the same tradition. It is a violation of the national and most local building codes, but few jurisdictions require an inspection to replace a breaker and even fewer electricians (even licensed professionals) want to go to the trouble of notifying the building inspector, paying for the inspection, etc. so breakers get upsized illegally.

In my case, it required pulling the face plate off of the breaker panel and removing all the breakers to reveal the severely burned bus bars. Definitely well beyond the competence of the average howeowner.

Your method does provide definitive data, but it is critically incomplete as it does not measure...

• the length of the various wire runs
• the guage or diameter of the wire used in each run
• whether the wire is copper or aluminum
• if the wire is aluminum
  • are the switches and outlets COALR rated?
  • have non-COALR switches and outlets been "pigtailed" with copper?
• Is everything in compliance with the building standards in effect when the house was built or the wiring last modified.

Homeowners are understandably reluctant to check these things because they may well fall into the trap I did when we bought our house. We ended up spending over $15,000 replacing the breaker panel and Bringing all the wiring up to the level of the current building code, which had to be done to pass icy inspection and get the power turned back on. Yes it has made us a LOT safer and we have not regretted it (we even got a break on our homeowner's insurance) but I guarantee writing that check hurt — A LOT.

Putting a "wheatie" in the fuse box was like putting in a 1000 amp fuse...dangerous beyond belief, particularly in view of the fact that you had already blown a fuse, i.e. overloaded the circuit.

Maybe it's easier than I thought to find someone who's willing to risk jail time to make a few bucks, or maybe NYC is just a tough jurisdiction; I dunno.

Your additions to my list (I did mention the need to know what kind of wires are in the walls.) are correct, but they kick it up from the realm of a concerned or prudent homeowner to that of a professional; they're really step two if step one suggests the need for it.

I'm certain that I'm nowhere near average in terms of what I'm running and how much power I'm burning ($60/month electric bills), so I'll ask how close you ever come to maxing out the draw on a line? I mean, it's not easy to draw 1440, let alone 1800 watts, for an extended period of time, particularly considering multiple lines and the fact that major appliances and other heavy draw equipment generally have dedicated lines or, at the least, are supplied by 20 amp lines.

And where that leads, of course, is to the likelihood that slolerner's friend's "problem" has nothing to do with upsized breakers or anything of that ilk, rather it's that her trailer probably just hasn't got enough lines, so short of springing for big bucks, the only thing she can do is follow prudent energy conservation rules, average out the load, and use common sense in dealing with what's left.

(It sounds like on top of your breakers having been upsized, the load was severely maxed out afterward, but why did you have to pay for the electrical work? Why didn't you, a lender, or an insurance company demand an inspection before the deal closed, in which case the price would have come down or the deal wouldn't have closed?)

Yes, that's backward, and demonstrates an incomplete understanding of the theory at work in a breaker.

Breakers are wired in series with the load. Resistance is additive, meaning you put three resistors in series, and their "effective combined resistance" is their sum. If you apply voltage to a string of resistors, that voltage (and thus the power) is distributed among the three resistors, proportional to their conductivity. IE the smaller the value, the higher the share they get. (you want the load - your lamp etc - to get most of the power, where it's useful) Even the wires in your walls are resistors, though they're small. So is the breaker. So you have a breaker, wires, a light switch, and a lamp. Ideally, you'd want the breaker, wires, and switch to be zero resistance, so the lamp took all the power, regardless of how low it's resistance was. But we don't live in a perfect world, so the wires, switch, and breaker will all steal a little bit of power and convert it to heat.

Breakers are made to steal a little bit more power, and turn it to heat. That heat bends a spring, and if it gets hot enough, bends it enough to push it over the roller and the switch snaps into the tripped position. (which is rigged to mechanically disconnect the power) So if the load has an unexpectedly low resistance (a short) then the breaker is taking a much larger percentage of the power, (and a lot more total power is flowing because the sum resistance has dropped dramatically) and so the breaker trips.

If you make the wires smaller, they will have a smaller cross-section area, and that will make them higher resistance per foot. They'll steal a bit more heat, but in doing so they also lower the overall current passing on the wire. (power = current^2 / resistance) That will slightly dim the light, and will slightly lower the heat created in the breaker. The breaker technically IS less likely to trip, but only because you're choking it off a bit. The problem there though is you're heating up the wiring in your house, which may pose a fire hazard. Especially if someone plugs in a bigger item (space heater?) to the outlet. That will severely drop the total resistance in the circuit (to increase power delivery) but now the small resistance in the wire starts becoming a significant percentage of total resistance in the line, and dumps a LOT more heat. And that is the recipe for an electrical fire due to overheating wiring. The breaker unfortunately has no way of "knowing" whether the power it's channelling is going mostly to the load, or is heating up the wires in the wall. So electrical code requires wires that are big enough to not get dangerously hot before the breaker trips. You want the breaker to get too hot before the wires do, because when the breaker gets too hot, it trips. When the wires get too hot, you get a FIRE in your walls.

The house I live in in Portland had a problem where all the kitchen and living room outlets and lights were on a single breaker, which kept tripping and tripping and tripping.

We had a neighbor recommend that we replace the 15-amp breaker with a 20-amp to solve the problem. I said "oh hell no" and instead spent an entire weekend installing 2 additional breakers and breaking it up into three separate, independently wired circuits--one for kitchen sockets, one for living room sockets, one for the lights. (That was when I discovered that some of the wiring was so old it dated back to WWII, meaning it was silk-wrapped aluminum rather than copper. All that wiring got pulled out of the walls and replaced with modern wiring.)

It was a ton of work, but it sure beats burning down the house.

Don't these two quotes contradict each other?

yes, they do

I don't understand how anyone thinks installing smaller gauge wire is a good way to make a breaker trip. It can only increase series resistance, and that can only lower current in the circuit, which can only lower the possibility of a breaker tripping. (unless you're looking further into the behavior of the users changing and that leading to a breaker more likely to trip... "hey this hair dryer is running slower, maybe I should turn it from Medium to High?")

I cannot explain the smaller vs larger wire scenario. What I do know is twenty years ago when I built a new home for myself I intentionally specified at least one wire gauge larger than specified in the national building codes. The building inspector made us pull out all of the oversized wiring because according to the national building code it was unsafe to oversize because the smaller wire would be more likely to force a breaker to pop.

MY limited experience with the building inspectors with whom I've had dealings leads me to the conclusion that you ALWAYS need to have access to the codes they cite in order to cross check the validity of their statements......in other words, "Those who can't DO must teach, and those who can't TEACH must administrate, and those who can't ADMINISTRATE must become building inspectors!"

Wiring specified for a particular circuit loading (amperage) is listed as a MINIMUM value based on maximum current anticipated and distance of the run....as an example, if a 30 amp circuit were to run less than 100 feet, then 10 gauge wiring is adequate, however, if the run were to be longer than 100 feet, then 8 gauge wiring would be REQUIRED by code due to the increased length.

Any decision to install the next larger gauge would not only be legal, but smart.

The applicable building standards were as stated by the building inspector. So I was presented with three choices...

1. Rip out the "oversize" wiring and replace it at a cost of $3500
2. Complete the house with the oversize wiring and not receive a occupancy certificate therefore no water and no electricity
3. Hire a lawyer for an estimated 10 to 15 thousand dollars to bring a suit against the city and state building codes with a potantial of going several time higher and spending years in court.

Which option would you have chosen as "smart"?

His being a building inspector should greatly increase the odds of his knowing this stuff, but it's not a guarantee

There may have been other alternate explanations. His actions may have somehow benefited him. (additional inspection fees, kickbacks from the contractors, etc)

Or iIt's possible that he'd never encountered that before and just got his facts confused trying to determine if that was a good or a bad change you'd made. Get someone that's doing the same thing day in and day out, and throw them a curveball, and it can really knock their train of thought off the tracks and lead to random outcomes.