I upgraded my bathroom fan to a bigger, more powerful fan. The problem is it is on the same 15a breaker as the 2 bedrooms and the bathroom. It is connected to a light above my tub and the three wires that come up from the dual switch on the wall via a junction box.
The house was built in 1942 and the wiring from the switch to the junction box is original, so the three wires have the cloth coating but look to be copper on the inside. The wire from the fan and the wire to the light above the tub are both newer.
The problem is every time I turn on the fan or the light it blows the breaker.
I even disconnected the light above the tub and replaced the wall switch with a single switch and when I turn the fan on, all the lights dim and it then throws the breaker.
I am wondering if I can replace the 15a breaker with a 20a breaker and how would I go about doing that? I already purchased the new 20a breaker.
Best Answer
No, you can't just "upsize a breaker". The breaker has a job, and you would break its ability to do that job. I gather you don't understand what that is, but fooling around with creaky old wiring... Well, I'm glad you asked first.
No, take the breaker back to the store. The only breaker you should be installing is a 15 amp AFCI. Where you have old/suspect wiring, AFCI is a fantastic safety system.
Anyway, that won't fix your problem
Breaker size is not the issue. Bathroom fans are considerably less than 1 amp, they certainly shouldn't be tripping a 15A breaker, for Pete's sake. Your fan has a big problem. It's not supposed to do that at all.
So either the fan has been miswired, or, the fan is defective.
Maybe it's time to call a competent handyman or electrician.