Performed A/C tune-ups on one American Standard system & one Amana heat pump system. Checked the electrical, mechanical and performance systems of the units. Cleared, cleaned, flushed and treated the drain lines and washed both outdoor coils. On the guest house system I found some biological growth on the coil and blower wheel. At the outdoor unit I found the starter is pitted and the fan motor is leaking oil. On the main house system I found the indoor coil is extremely clogged with biological growth and very rusted. The air flow across the coil is low due to the growth which could cause the system to freeze over if it runs long enough. There is also some growth on the blower wheel and there is no water safety switch on the system. I spoke with the homeowner about my findings Both systems are operational at this time.