My air conditioning keeps freezing up. There is ice all over it . It doesn't cool the house when it does this , and I have to shut it down to defrost it. It is central heat and air. I live in fla and it is very hot here.

3 things cause it to freeze up. 1) lack of airflow. Are the coils clean. Is the filter clean and installed properly? Are both the fans operating properly? 2) low on refrigerant. You will need a quilified tech to check this. 3)a restriction. You will need a quilified tech to check this as well.

The esquire1 is correct. I, too, live in Fla, and just went though the same thing. The evap core was corroded and leaked until the compressor on the outside unit seized. The entire system was contaminated by the acid created. The entire system got replace a few weeks ago. I smile every time I open my electric bill ( the new unit is much more efficient and so much quieter ) It's hard to not love a Trane!