A/c lines freezing when I run my car for a little while.

Question

A/c lines freezing when I run my car for a little while.

Answer 1

Coolant is low.

I know that sounds bas ackwards, but that's usually the cause.

Answer 2

The AC runs colder when the refrigerant gets lot. It can freeze the coil in the car into a block of solid ice.

Answer 3

Might need to have your freon level checked.

It could be a problem with your condenser though.

It's been a long time since I had anything to do with A/C units, but I don't think a sticky expansion valve would cause this type problem.  A bad expansion valve usually causes the A/C not to cool at all.