[left]The AC unit was added to my existing heating system about a year ago. So it’s relatively new. I live in an area which is hot in the afternoon and cool at night. Every time I make a switch from cool to hot and vice versa, moist, musty air blows out, and humidity in the house raises about 10%. The wet air usually last about 3 mins, and then everything runs fine. What’s wrong with my hvac? Please help. [/left]

Hi My unit is over 14 years old...I have no idea how to tell how many tons it is. It is a York, model H2RA036S06D [URL]http://johnsonsupply.com/york2001/PUB/55046/OUT/TG1Y.PDF[/URL] Some of the fins on one side are disintigrating when they are touched. No dog has EVER lived here to have peed on them, so perhaps it is from sprinklers? Other areas of fins are white and hardened. Main problem, it has stopped cooling completely. Coolish air comes out but it never reaches temp thermostat is set at. this morning, i noticed ice completely over the two pipes on the inside (i have no idea what they are called, or what is the compresser vs condensor). Ice was also on the exterior where the tube comes out at the bottom of the unit and peeking thru areas of the tube that runs into the house where the insulation has cracked open. I turned it off, several hours later, all ice gone. I have repairman coming next week. it has been like this for 2 weeks. I have a feeling i have to get a whole new unit, yes? if so, i want to be prepared to hear this and know what to expect cost wise. What is a good unit? how do I know how many tons I need? where does it say tonage on the current label on my unit? I see nothing that says "tons", I see a weight of 3.5 pounds, not tons. what the heck is that? if i don't need to replace the whole unit, what DOES need to be replaced? what can I expect costwise? Thank you in advance.