Answers

What are the causes of a Hot Circuit Breaker?

Since electricity produces heat, it is normal for a circuit breaker to feel slightly warm while it is running, however, if your circuit breaker feels too hot to the touch, your breaker could be malfunctioning.
Breakers are designed to run at 80% of its maximum power capacity, so if it’s running beyond that, it could be exceeding the safety rating, which is a hazard. If it is a case of an overloaded circuit, you may have an outdated circuit breaker which does not meet your homes energy needs. Otherwise, you may have an improperly-installed or defective breaker that is malfunctioning and requires a repair or replacement.
A faulty breaker can be very dangerous. It is not safe to attempt this type of electrical work on your own, so if you are experiencing this problem, contact an electrician immediately.