20 amp AFCI

Dehumidifier tripping AFCI - DoItYourself.com Community Forums

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Oct 1, 2011 - My dehumidifier is on a 15 Amp circuit with an AFCI breaker. ... What I mean by that is that it can run without tripping for days or only a few hours ...

Hi James, I'm an electrician and will try to help you out with this problem.

An AFCI combination breaker is a type that will open a circuit when either condition exists: (1) A sustained current (in amps) load greater than 80% of the breaker's rating is present for a predetermined length of time. Your 15 amp breaker should hold a 12 amp load 24 hours / day; but a 13 amp load may only be passed for several hours - a 15 amp load only a few minutes or a 17 amp load only a few seconds and (2) Whenever the internal circuitry of the breaker sees load disturbances that mimic an arcing short circuit as programmed by the manufacturer.

Since you have lowered the load on the circuit in question, it is probably not an overload condition, but rather a problem with the remaining items on the circuit or wiring in the home. I suspect that you did not remove the lamps from the fixtures and wonder if you you are using CFL (compact fluorescent lamps) in them. Some CFLs and regular fluorescent lamps can "look" like an arcing short (esspecially when fisrt turned on) and cause a false positive for this condition. Remove any / all florescent lamps (or leave the switches off). Also, make sure any motor loads are disconnected, too. The motors that have "brushes" (looks like little sparks inside) can have the arcing signature that the AFCI thinks is a problem. Once you've cleared all these items, try again.

If it still won't hold, you may have a bad AFCI breaker. You should not attempt replacement if you do not know what you're doing in the panel. This will be your lowest cost fix. If the problem still won't go away, you're going to need to spend some time (or money on an electrician) checking all the connections at each outlet, switch, fixture, junction box, etc. to find the source of the fault. In rare instances, the fault may be a result of supporting staples being driven to hard during construction of the building.

The GFCI test / reset operations have nothing to do with an AFCI tripping condition, as they work completely different from each other.

Good luck!

if the breaker has tripped the test button won't do anything ,, for the breaker to trip something down stream of it is causing this to happen,, check all the switches and or receptacles in the circuit that are controlled by this breaker, 3 types of line problems cause tripping,, ground to line, Line to line, and line to neutral. in this ,, also consider that extension cords, faulty appliances , ( lamps, radios, anything plugged in with a feedback short ) will cause the breaker to trip. even a nail to hang a picture that pierced the wire can cause this, add to that , a AFCI breaker will trip much more easily than one thats not, or even a GFI breaker, , try this, if you have the knowledge to do electrical work in a panel, if not get someone who is, switch the tripping breaker with another one of the same value, ( in this case 15 amp) see if the one you put in place of the one thats giving you problems trips. If it doesn't, you have a weak or bad breaker, so just replace that one, if it does, your going to have to trace out that entire circuit to find the reason for the feed back into the panel

You should not have multiple GFCI devices in any one circuit. Change out the outlet and label it
GFCI Protected if necessary...Your problem of nuisance trips should go away.

John

AFCI (arc fault circuit interrupter) devices such as yours rarely have a problem - but a trip indicates there's a problem with the circuit it is supplying. It like a fuse - they generally don't go bad by themselves - but do when there's a problem.

AFCI have the unique ability to detect arcing - or sparking. An arc or spark is very hot - and is a fire hazard. An AFCI can sense this condition before it is even seen - if it were in an exposed place that it could be seen and shuts off power. Arcing can occur at a loose connection, such as in a wirenut, terminal screw, etc. The AFCI can also detect when a cable support staple has been driven to deep and crushed through the cable insulation and is beginning to cause a high resistance short circuit. Because these problems often occur where they can't be seen, it is a labor intensive job to locate and repair the problem. Sometimes, entire sections of circuits must be re-fed due to the location of the fault. Due to the complexity of searching for the fault, you may want to call an electrician to clear the fault for you. You should not under any circumstances replace the AFCI with a standard circuit breaker or GFCI type circuit breaker. You may however, change it with an adjacent AFCI breaker to determine if the issue is with the circuit - or the AFCI. If the AFCI trips on the new circuit, you should accept that it has failed and should be replaced. If the problem stays in the same circuit, then the AFCI is good and the problem is in the circuit somewhere.

Here are a couple links to youtube videos that may help you understand the how and why of AFCI devices: video 1 and video 2. A link back to Siemen's site on AFCI is here.

I hope this helps and good luck. Please rate my reply - thanks!

Hi, these ground fault Interupter or AFCI breakers are made for normally outdoor circuit and and circuits around water such as your bathrooms. I would turn each one off, take a screw driver and make sure each terminal to each breaker is good and tight. You say this is a new home, so it makes since this is a problem. This can be done safely, as with the breakers off the screw terminals are dead, always be safe though when working around high voltage. If you continue to have this problem, you would have no other choice than to get a qualified Elect. out to see if they have your G.F.I breakers wired on the right circuits? This sounds to me this also may be your problem. They are made to trip around sinks with lets say your lady of the home using a blow dryer on her hair and there is a slight voltage leak in the cord of the appliance? This is when the breaker should trip due to the chance of shock!!

They can be defective, but usually not. It is usually something that is plugged in that will not operate on the arc fault circuit. Brush type motors are bad as they are actually arcing at times. Unplug all devices, and try to find the culprit. These are for your safety, and once you find the problem devices you should be fine.

It's definitely not related to the 20 Amp breaker. You do mean GFCI, right? The kind built into the end of the cord on the air conditioner, right? The GFCI is either detecting a ground fault (which means it's doing it's job and there is something wrong with the cord or the unit) or you have a bad GFCI. If the GFCI is in the wall receptacle, that could be a different story.

connect the neutral from the circuit to the afci breaker, and run the neutral that came on the afci breaker to the neutral bar in the panel. Make sure that the neutral that you connect from the circuit to the afci breaker is the one that belongs to the circuit that you're protecting or the afci wont work.

You could install a standard GFCI in line at each component ( heater, pump & timer) or you could install AFCI breakers similar to what are required in many residential codes (provide the same protection at the panel not at the location... http://www.cpsc.gov/CPSCPUB/PUBS/afcifac8.PDF

The AFCI breakers will need to match your panel type (siemens, GE or Square-D) and the amperage/configuration.

I would install them at the lowest level (closest to the components) in the system to reduce possibility of fire in the wiring between the components and the afci breaker.