What could be wrong with my home air conditioner?

you said Home unit ? central unit outside on pad?? or on side of home? it really sounds like your low on coolant by about 3lbs. as far as coils in air-handler, get coil cleaner spray on and rinse or use lite toothbrush if really full of dust. so if your low on coolant the outside unit wont be sweating, so check it ! I lived in the SW/FL area for 40yrs and have done many. hope this helps if not ,an A/C heating web site has great how to,. let me know if ya need it.

We had a problem like that and all it needed was a new fuse and a line had a hair crack line in it so the man that was here tapped it and sure enough it was fixed. The guys that came out a day before said we needed a new system @ $7000. Hmm I think they were rip offs. It's all better now with the new fuse. Do not hose it call someone off Craigslist first. AC companys charge $85 just to knock on your door.

He may be correct. A clean condenser will deliver colder air.

You have to turn the POWER OFF at the disconnect box, next to the unit. Turn the t-stat OFF, too.

Unscrew the top and turn it to one side and don't pull the wiring or bend the fan blades.

Take a garden hose on medium pressure and wash it from inside out for 20 minutes. Also, get all of the leaves and dirt out of the bottom out first. You will get wet.

Then, put it back together and turn the power back on. Good luck

Clean BOTH coils.....for a start; then check refrigerant level, keep the inside filter CLEAN.

(there are inside coil cleaners available that do not require the use of a garden hose but I have seen evaps I had no choice but to use a foaming scrubbing bubbles type cleaner and a hand spray bottle of water refilled many times to get clear)

It is also usually called as duct cleaning..... I think it is not too bad idea