ice on expansion valve
I had freon added to my AC last summer but the service technician was having some kind of problem (wasn't getting temp or pressure? drops??) with what he was measuring at the outside unit. He later came in and looked at indoor unit and found expansion valve on outside of it. He said it needed replaced.
Part was backordered but never arrived. I turned the AC off because it was not producing any cooling. After the valve thawed I turned it back on and the valve worked the rest of last summer.
This spring the valve is icing up again. I turn off, thaw, and back on but it keeps icing up.
Is expansion valve icing up because the valve is bad or will it ice up if I need freon again?
Could be a number of things low on refrigerant or possibly moisture in the system causing the ice. Call a trusted HVAC company to check your system out and ppreform the proper repairs.
Ice on the TXV
If you call the same company back, ask if they really work on systems with expansion valves.
Low charge can cause it to ice up, also moisture inside the refrigerant system can also cause it to ice up. Low total system air flow can also. Is there any ice on the refrigerant line out side on the out door unit?