Our unit has been cooling less&less. This afternoon it seemed to warm inside-it had been a rainy cool day. Can hardly feel any air blowing from vents-if any. Looked outside at the unit, one of the pipes from the unit to the house was iced over. Turned off unit until ice thawed. Just now turnedit back on-still feels like no air blowing. : (

More than likely you have a dirty set of coils blocked by dirt. The best way to clean them is to pump the unit down by closing the high-side valve at condensing unit, pumping gas into condensing unit, then closing low-side valve, and cutting pipes at inside unit and welding them closed so you can remove the coils and apply alkaline coil cleaner and pressure wash them. Alternatively, you can remove the indoor blower fan (with power off) by sliding it out and then you can see both sides of coils on many units to spray down with alkaline coil cleaner and wash out coils and blower fan, too. It's a big job that AC companies hate to do. You will also have to clean the outside unit and oil the fan motor, but that's easy.

Thanks you for the quick reply. I was wondering about the coils. The coils had gotten cleaned in the summer of 2011. I believe the unit had the same"symptoms" then. Hmmm... I can't weld so I speed I can attempt removing the blower fan to see/vlean the coils. My husband works a million hours a week out in the oil fields. Im a stay-at-home mom & handle most home repairs,maintenance & handyman jobs! This alkaline coil cleaner.. . can I find it at Home Depot? And is this somethingi should plan to do every couple of years? Is very dusty here, and we do have 4 spoiled dogs that live indoors. I'd bet the coils are dirty w/dust & dog hair!
Thanks again!