I have a Mammoth 100% outside air watercooled fresh air heat pump that is 2 years old. It serves a Carecenter facility for the elderly. Got a call Sunday eve that both elevators in facility were down. Found Ground fault circuit breaker had tripped knocking out panel that serves elevators and outside air unit. Both compressors in unit had burned out, blew a hole thru "pecker head" electrical connections at compressors. Big puddle of oil under compressors, obviously both refrigeration circuits out of gas. Also knocked out Metasys controller, but blower fan still works. Warranty no longer applies, only one year. manufacturers warranty on compressors only one year. Did not pickup 5 year optional warranty. Company that installed (THERMA) sending there "TOP NOTCH" Tech next week to determine cause. Anybody have any Ideas which may have caused problem??? Also burned off one load side wire off of contactor for compressor circuit #2 which is the one that kicks in on rise in heat load. Checked all electrical connections in MSB Panel and sub panel all very secure, no burning of insulation. No other electrical problems in buiding.