Quote Originally Posted by nobbie48 View Post
The breaker could be getting old as well. As FireSTaRT said you can check the element with an ohmeter if you are up to taking things apart. Conductor to conductor should be in the two digit range ohms. I'm guessing 15-20 ohms. Conductor to ground should be millions of ohms but a few hundred thousand could be OK. I don't work with HW heaters but those readings should work.
If you have a clamp on ammeter (Amprobe) use it to test. The two leads should be drawing the same load. If not there is a short to ground. Assuming the heater is working on 240 volts there should be two breakers. If the same one is tripping, switch the the breaker positions to see if the problem follows the breaker or the line.

Cleaning the tank won't help the element if it has failed but we'll give you an extra marks for good housekeeping.

BTW you should be wearing arc flash gear when working on an open panel. Molten copper is nasty stuff when it blasts you.

it's either breaker going, and i had replaced them once. last set would trip over and over, now this set is trying to trip more often