Kitchen Large Electric Appliances - Dryer tripping breaker

My clothes dryer has been tripping its circuit breaker recently. The house is 15 years old and I have not had this problem until recently. Thre have been no new appliances added to our house. I have not yet had the dryer checked out because I wondered if something else could be wrong. Do breakers go bad? Do they trip in error? Any thoughts on what I might look into before I have the dryer checked out? Thank you.

So this is the same dryer and the same circuit and they've been running fine for years? And nothing has changed?

Breakers can go bad, but it's pretty rarely. First check to make sure the vent pipe is clear. If the vent clogs, it can cause the dryer to run much longer than usual, and eventually burn out the heating element. If everything seems fine, you might as well change the breaker to see if it helps, but I'm not overly confident in that.

As John said, breakers rarely go bad. However, changing the breaker is probably the cheapest thing to do first. If, by chance, you have another 30 amp circuit, you might try swapping the breakers. However, most houses don' have two 30 amp breakers, unless they have electric heat, so swapping breakers is probably not an option.

To try the breaker theory, buy a new 30 amp breaker that is designed for your panel and replace the existing one. I the problem still persists, then check (or replace) the dryer.

I would check the plug-in connection to the dryer to ensure that it has not overheated and corroded, thus drawing excessive current. Also check the dryer cord connections in the back of the dryer for the same situation. I had to replace my daughter's dryer terminal block for that reason recently.

The main load in an electric dryer is the heating element which operates at 240 volts. There is also an electric motor (~1/3 h.p.) that turns the drum. I checked the manual on mine and it says it has a 5400 watt element (22.5 amps @ 240 volts) and a 120 volt motor with a full load amps of 5.9. This means there is 28.4 amps on one leg and 22.5 amps on the other leg if everything is normal. If the rolling friction of the drum increases due to age or if the washer leaves the clothes very wet, this load on one leg could easily get over 30 amps. The higher current drops the voltage to the unit which results in less heat from the element and even higher current to the motor. Add in the aforementioned problems that could cause longer run times and you have a combination of factors that could be the cause of the breaker trips.