What is wrong if there is ice forming on the outside unit of your house air conditioner?

I see this happen a lot. The thermostat is turned down way to low (60 degrees or lower) causing ice to build up on the air conditioners condenser coils. Which causes the air not to get through the coils. The icing of the condenser creates a blockage and the air conditioner doesn't cool the house or room. Making you think it is not working. If not corrected the compressor will overheat. (Not Good). Turn the air conditioner off until the ice has melted (probably 24 hours). Then turn the air conditioner back on with the thermostat set to 68 to 70 degrees and it should go away. If not call a technician.