Your service entrance has only 4 breakers? Do you mean a main breaker plus 3 branch circuits, or the main plus 4 branch circuit breakers? How many amps is it's rating? Do you have several unused knock-outs in the box? How many of the circuits are 220 volts? You state that you keep filpping the breakers. I assume that you mean that the breakers continue to trip due to overloads. Is it only one or two that trip, or do all trip at various times?