Try replacing the breaker. Sometimes when the breakers get old, they tend to
trip at a lower current. The internal contacts in the breaker heat up more
because they are warn, and thus the breaker trips.
If the new breaker is also tripping, then you will have to have the dryer
serviced. There may be problems with the heating element, control board, or
the motor. Rather than try to fix that yourself, it will be more reasonable
and safer to have an experienced service person do this type of work.
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