Bath fan tripping the breaker

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The problem and diagnosis might be obvious to you, but others with experience have valid opinions and input.

No one appointed you king of the forum, we are free to suggest ideas that have worked for us in similar situations.

Jeff first of all I am not going to get into an argument with you - not my cup of tea!

I was simply bringing to all respondents of this tread including yourself that the OP stated in his first post that the issue happens when the switch if in the off position not the on possition which is something that can be overlooked easily.

Your signature states the following - "Professional Handyman, NOT a Licensed Pro" - Well I am a "Licensed Pro" - I took years of electrical classes in a good trade school and was a certified and licensed electrician until I retired because of physical issues so let's not go there Jeff.

I was not stating that the replies so far were incorrect at all (including your suggestions) - again, I was just trying to bring to everyone's attention (something that can be overlooked easily) that the problem happens when the switch is in the "OFF" position not the "ON" position - that's all. Thus there is very possible a mis-wire that Kat2014 did.

Your post #20 even confirms this theory that there may be a mis-wire. "The gfci outlet might be wired wrong also, they often are."

I never claimed to be "king of the forum". I have been a member of this forum much longer than you have been and have given many OPs helpful and useful information that is within code and safe.

Let's get back on the right track here and attempt to help Kat2014 with this problem once he deals with the other issues of the storm damage.
 
Lets keep in mind everyone what the OP stated about the fan

"First one was fine. Second one (identical) not so much. I turned the power back on and the fan and lights came on as normal, but when trying to turn the fan off, the breaker pops." Which means the fan runs fine.

This occurs when the OP turns the fan off. So to me this states there is a mis-wire and causing a dead short. Would not matter what type of breaker the OP has installed. A dead short will trip a regular breaker, AFCI breaker, GFCI breaker or a dual function AFCI/GFCI breaker.

Kat2014 please confirm that the fan runs fine but when you go to shut the fan off (turn the switch to off) that is when the breaker trips. If this is the case that when you turn the fan off it trips the breaker you need to check how you wired it. Give us some details of the wiring because it is obvious that you did not wire something correctly when hooking it up.

You make a good point, something is certainly wrong, but the OP hasn’t provided sufficient information to come to that conclusion yet.

The OP hasn’t specified if they changed any wiring on the switch or elsewhere in the circuit. They also haven’t said if the previous fan had failed or stopped working for any reason. We don’t know if the fan is protected by GFCI or if there is simply another outlet that is on the same circuit but ran in parallel to the fan. It’s possible the outlet trips because the circuit loses power and is throwing a red herring into the mix.

The point that you brought up that I like is that sometimes it can be easy to assume people understand the basics of electricity and that allows things to be overlooked. Incorrect wiring is a possibility that shouldn’t be thrown out. But with the limited info that we have of this circuit it isn’t the only possibility out there.

To the OP, can you clarify the circuit a little better and let us know what level of understanding you have about electrical circuits, and what test equipment you have access to. Will the circuit trip when the breaker is reset with the fan switch in the off position? If not will the breaker trip when the fan is turned back on? Those sorts of details will help us help you.

Jeff’s suggestion to swap the blower assemblies is a simple and easy test to determine the motor if the OP doesn’t have an electrical meter of some sort.
 
You stated that there was no need to swap fans or anything else.

Thereby declaring my suggestion wrong and unnecessary.

That is what I have a problem with.

Since that method of swapping identical parts has helped me solve many head scratchers.

And others I know often use this technique as a diagnostic tool.
 
We all need to calm down a little here. Saying with my Admin. pants on.


That being said and I hope that is all that will need to be said on the topic.


Electrical troubleshooting is tough on here as each person coming with a question has a different level of abilities. I would just stick the fan on my workbench and wire it up with test leads and make sure it worked properly but that’s not what I would suggest for the OP.


As to @afjes_2016 thoughts, I’m trying to think of a case where a switch passing power in the on position can cause a dead short when opened. Maybe a defective switch but having it happen with both the old and new isn’t logical. The only case I can think of is if the OP picked up a 3way switch by accident and wired it in weird. Every switch wired wrong that caused a dead short I can remember caused the fault when it was turned on.


Sounds like the OP will be busy a few days and then we will figure it out.
 
Just being the "Devil's Advocate" ...What if there was a 3 way switch installed prior?? (Just an off the wall thought)
In 40+ years of installing and troubleshooting I've never seen a problem like this.
Without actually seeing the wiring I'm at a loss. I would have pulled the switch out and touched the wires together and seen what happens.
Way to step in Bud
Sorry ..wrote before I read your post.
 
Just being the "Devil's Advocate" ...What if there was a 3 way switch installed prior?? (Just an off the wall thought)
In 40+ years of installing and troubleshooting I've never seen a problem like this.
Without actually seeing the wiring I'm at a loss. I would have pulled the switch out and touched the wires together and seen what happens.
Way to step in Bud
Sorry ..wrote before I read your post.


Nothing surprises me and I have found a 3way switch used as a regular switch before with nothing attached to the other carrier screw. So who knows. We will have to wait for the OP to take some pics and show us.


Because we all know what happens when we assume.
 
If the fan is wired into the GFCI, make sure it's wired to the LINE side of the outlet. GFCI's get touchy with age. Might need to change the GFCI if you want to use the LOAD side of the outlet.
 
Thanks for the update kat2014 and glad you got it solved.

Hope all is well with the storms you had a while back (mentioned in this thread). Hope all are safe in your family.

Be well
 
If the fan is wired into the GFCI, make sure it's wired to the LINE side of the outlet. GFCI's get touchy with age. Might need to change the GFCI if you want to use the LOAD side of the outlet.
Yes, the GFCI was changed out as well - when all this started.
 
Thanks for the update kat2014 and glad you got it solved.

Hope all is well with the storms you had a while back (mentioned in this thread). Hope all are safe in your family.

Be well
Well, we recently got a new roof put on, and that was an expensive but wonderful relief - no waking up to the sound of drips during a storm anymore!!
 
I'm very glad you got the problem fixed & it was something simple. Sorry to hear you got a bad switch but at least you figured it out. Also sorry about the storm damage but glad you have a new roof. My area may be about to get hit with hurricane #3 in a few days so I can sympathize.
 
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