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Discussion Forum

30 amp breaker ok where a 20 amp went before?

kyrral | Posted in General Discussion on January 14, 2010 03:58am

I have an older panel box. One 20 amp circuit goes off about once a month. A 25 amp breaker isn’t available. Would a 30 amp cause problems. Because the breaker trips so few times I assume its only getting a load of 21 or 22 amps before it crashes. I can’t rewire. Any other solutions.

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  1. pm22 | Jan 14, 2010 04:23pm | #1

    Hell no! The breaker is sized to protect the wires. You probably have #12 wires and they get 20 amp breakers, no more.

    Perhaps you can move some circuits around to lower the load.

    It is possible to rewire some of the circuits and add on.

    ~Peter

    1. JTC1 | Jan 14, 2010 05:32pm | #4

      I'll vote with you --- may be
      I'll vote with you --- may be old breaker which is getting "weak" or just plain defective --- I would certainly try replacing the breaker first before going very deep in the circuit. $6.47 and 10 minutes work.

      I had a Square-D panel in a previous house. I rewired the entire house before moving into it. All new, QO style.

      When rewiring, I decided I should run a separate 20A circuit to a location directly under a window for the express purpose of using the 20A single receptacle to power a window A/C unit in the master bedroom.

      After about 4 years the finances had recovered enough to actually buy an air conditioner and use my special receptacle. Other than plugging in testers this receptacle had never been used for anything.

      Mounted A/C, plugged it in, turned it on and pow - the breaker tripped in about 1 second. Reset breaker - same thing.

      Plugged A/C into a different outlet in the same room - also 20A, but not dedicated. A/C hummed along just fine. Traded the two breakers in the panel. Same result but now reversed - dedicated circuit works fine, non-dedicated trips in about 1 second.

      S-s-l-l-l-o-o-o-o-w-w-w-l-l-y-y-y my "mental light bulb" came on...just a faint glow at first......"Well golly, duh ya 'spose thet breaker mat be no gud?"

      Replaced breaker and never had another problem for the remaining 8 years I lived in that house.

      Ever since then I have always been somewhat suspect of the breaker itself and always "load" any new or replacement breakers at the time of installation. My heat gun provides a fairly decent load for most circuits.......

      Jim

  2. User avater
    xxPaulCPxx | Jan 14, 2010 04:37pm | #2

    It might also be possible that the breaker is wearing out with age, and is tripping too easily. Replacement breakers aren't that expensive - like $5. Try that first to see if that helps.

    BTW, I ran my whole house off a single 40amp breaker while I converted from my old service panel to the new one. What exactly is on that circuit presently - maybe we can help you add up the load to figure out where the problem might lie.

    1. brucet9 | Jan 15, 2010 02:09am | #7

      "Replacement breakers aren't
      "Replacement breakers aren't that expensive - like $5."

      If that is an old panel, Zinssco, Bulldog, or other obsolete style the replacement breaker could cost $40 or more.

      Still better than over-sizing, though.

      1. Piffin | Jan 15, 2010 04:28pm | #11

        or it could be an old cutler-hammer and the entire panel should be replaced.

  3. User avater
    rjw | Jan 14, 2010 05:14pm | #3

    As noted - absolutely not.

    How old is the house/panel? Who is the manufacturer of the panel?

    1. junkhound | Jan 14, 2010 09:11pm | #5

      You can always use 2 15A breakers in parallel, aint thet rite??

      1. User avater
        rjw | Jan 15, 2010 02:36pm | #9

        >>You can always use 2 15A breakers in parallel, aint thet rite??

        Huh? You mean like any standard 240V circuit? As they are on different legs of the incoming supply, I don't think they are "in parallel"

        Even if they were on the same leg, I suspect it would simply mean that if te 15A 9plus safety margin) were exceeded, they would both trip....

        I'd call out such a set up for further review based on the fact I've never seen such a setup even described, much less used....

        1. DanH | Jan 15, 2010 08:40pm | #12

          Aih tink he vas kidding.

  4. barmil | Jan 14, 2010 09:31pm | #6

    I live in a town filled with older houses, including my own, built in the 30's. All of these old houses had 60 amp systems, consisting of four 15 amp circuits protected by fuses and using 14 gauge wiring. Okay for their time, I guess. Then people started using irons, coffee makers, hair dryers, etc that caused the fuses to blow. So, the popular solution was to replace the 15 amp fuse with a 30 amp fuse (if not a copper penny). No more outages, hooray! I'm sure that this kept the fire departments busy and contributed to urban renewal. No modern home should have less than a 150 amp circuit breaker box, in my opinion, and maybe more than that for the future. It doesn't really cost that much more to increase the amps at the time of installation, even if you haven't thought about future needs.

    1. JTC1 | Jan 15, 2010 07:56am | #8

      60 amps in the 30's - that
      60 amps in the 30's - that was "luxury" service around here.

      The first house which I owned was a 3 story duplex (I had one side) - 5 bedrooms, 2 baths, LR, DR, kitchen, full basement. Built in 1929.

      Electrical service was 30A, 120v. No 240v available in the house.

      Service entered the basement into a 30A cartridge fuse housed in a fused disconnect box. 6" cable exited the shut-off switch into a 2 fuse panel - two 15A screw-in fuses ran the entire house.

      One 15A powered every outlet in the house (one per room, none in baths), the other 15A powered all of the OH lights. I'll bet it was exciting when that one lighting circuit fuse blew after dark.....

      Jim

  5. Piffin | Jan 15, 2010 04:25pm | #10

    go ahead and increase the breaker size, as long as you don't mind burning the house down.

    Odds are, that the breaker itself is worn out, and all you need to do is replace it, but it would be wise to have an electrician check the circuit out. One thing that can increase loads drawn is a bad contact at a receptacle heating up and increasing resistance. That is something you want to find out about, rather than ignore.

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