How hot is "very hot"? It's normal for a breaker to get a bit warm under
load. If it's getting unusually hot, change it with one of the *same*
If you are *sure* the whole circuit is wired with #12, you could go with
a 20A breaker, but there's no reason to. Excessive heat indicates a
problem with the breaker itself or the connections to it.
Hot to the knuckle. Not that I have to move my knuckle off of it, but
Connections are solid, I'll go with a new breaker and if that does not work
I'll check the load and wire size again and see if a 20 amp will be in order
You shouldn't replace it with one of higher rating. That's akin to
replacing a fuse with a bigger one. The breaker sizing is based on the
circuit and components downstream from the breaker and what they can
'Hot' *could* be a simple loose termination. If you're comfortable with
the work, open the breaker and check the wire(s) under the screw and see
if the screw is properly tightened.
Or the breaker could be defective. If you replace it, use the *same
rating* not a larger one.
It could be a bad breaker or loose connection. Make sure the screw clamp
on the outgoing conductor is tightened properly. Also, try reseating the
breaker on the bus.
I've seen the spring clip on the bus (input) side of the breaker go bad.
It gets hot and that raises the resistance at that point further. This
can go on until the tab on the bus becomes damaged due to the
overheating. The breaker will have to be replaced in a new position. The
old position on the bus can never be used again. Usually on crappy brand
Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com
I had this happen in a rental house I lived in about 10 years ago. I got
home and the compact fluorescent bulb in the porch light was flickering
madly and then found that other loads on that circuit were the same.
Went out to the garage and I could hear a sizzling sound from the panel.
Shut off the main and started looking around and found exactly that
issue, and then noticed that the terminals in the vacant spot were
burned as well. I ended up using an air powered grinder to clean them up
and installed a spare breaker I had and it worked the rest of the year I
lived there. I let the landlord know but they didn't seem real
interested in dealing with it.
The connection can get loose enough that there is arcing between the
breaker and bus. You can hear a sizzling sound (not the normal humming).
A bad breaker can be found with the old screwdriver-as-a-stethoscope trick.
"Very" hot is is subjective. Breakers have a thermal trip so they do get
First turn the breaker off and tighten the screw that holds the wire at the
breaker. If it is excessively loose that probably fixes it, if not
Assuming you are using copper wire.....
You need to measure the amperes going through the No. 12 wire with a clamp
on amp meter at the breaker.
If there is more than 12 amperes and the lights are on for more than 3 hours
you should increase the size of breaker to 20 amperes. No. 12 is good for
20 amperes and good for 16 amperes for a continuous load (3 hrs or more).
The breaker and terminal should not be hotter than 60 degrees C. or 140
degrees F. Hot water from the tap is at about 160 degrees F so that should
give you and idea. If the wire has an insulation of THHN, XHHW, THHW, and
the breaker has terminals rated for 75 degrees C. and the wire is not part
of a NM cable (commonly called Romex) and the panel is rated for 75 degrees
then the breaker and terminal can be at 75 degrees C or 167 degrees F which
is pretty darn hot.
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