We have one of these units on a well pump that when checked today, the circuit board inside is burnt just above the little coil under the green circuit board. The holding tank is empty, pump not working. What would have caused this? Possibly a fried pump or can I replace the circuit board and all's well. Right. The model # is 5800020100/ Looks to be a 1996 vintage. Any help would be appreciated.

Darol