76 Scamp A/C

Pete, the frost, out the vents happens down here in the south, when the humidity is very high. The cold air coming out the vents condenses the humidity in the air right at the vent outlet. But actually it should not occur, if the evap temp control is set correctly. I don't like to see the discharge air below 40 degrees, as the discharge air temp is typically 5-10 degrees warmer then the evap temp, and you don't want evap freeze up.