Turn your control to fan and on, if the fan runs, your problem is most likely as stated above. Your freon has leaked out to a point that it is tripping the low pressure sensor. Heavy condensation is a sign of low pressure or very high humidity in your house, possibly caused by the drain being clogged or restricted form the collection pan to the drain line.

There are a few members here that do HVAC for a living, but I can't recall who they are, check the member owned business thread they may be listed there.