a/c freezing up

[PattieAM]

My AC would frost over if I had the thermostat on the coldest setting.  When I reduced the thermostat to about 3/4 setting, it no longer frosted over (whether the fan was on high or low setting).  The compressor would kick on and run for a while, then cut off and the condensation was ejected rather than freezing on the coils.  (Maryland/Virginia summers are extremely humid and that plays a part in the amount of condensation)

I was told the AC unit ran about $500 with installation by the dealership about the same cost if I'd bought it after market (back in 06).  By having it installed when I bought the unit, it was less.