Expansion Valve Stuck Closed
Our Central A/C has been blowing warm air for about the past week or so. I have tested with a new thermostat, completely cleaned the outside unit, cleaned the evaporator coils/fins, and tested continuity and voltage on the wiring harnesses. All components appear to be running properly, although I have very little knowledge of A/C systems. I finally decided to fork out the cash for a service call and the technician came to the conclusion that the Expansion Valve was "stuck" in the closed position. The system is still under a limited warranty for parts and he offered to replace the valve for a fee of approximately $400 for labor costs. That price instantly raised a red-flag for me so I declined, paid him the standard service call fee and sent him on his way. Like I said before, I have little knowledge of A/C systems but I felt the small service call fee was reasonable to be cautionary and do some researching first. Since I am a Navy Aviation Electronics Tech, it is my nature to at least attempt a fix on my own with as little resources and money as possible; we're no strangers to launching F/A 18's into the sky with duct-taped wings (just kidding...just kidding). So after doing some extensive searching on the internet for my problem I am still at a dead-end. I have read opinions that many techs can falsely diagnose the TXV as probable cause of failure. Apparently the indications of a faulty TXV are similar to other components (sensor bulb, among others, whatever this is). So I am seeking a possible "quick-fix" solution until I can afford to replace the component or even a solution that can fix it permanently without having to pay someone to evacuate the system and replace the valve. Is there any "myths" out there I can try? I'm thinking in terms of the potato to remove a broken light bulb theory or toothpaste to repair a scratched CD type of theories. I was thinking about turning the heat on for about an hour, or even turning the A/C on and blowing on the valve with a hair dryer or something. I am pretty desperate. Please help if you can, I am in TX and my wife and kids are starting to get cranky and it is dangerously hot this time of year.
Thanks in advance!