Kittyangel, the only way to know if your system has enough capacity to heat and cool your addition is to have you or someone else do a heat load calculation on your home. Anything else would be a wild guess and you and your family probably wouldn't be comfortable.
yerry, look at the inside of the access door on your unit. There should be a chart in the wiring diagram that tell your what the trouble codes are.
"The physician can bury his mistakes, but the architect can only advise his clients to plant vines." -- Frank Lloyd Wright