[AC_Hacker]

Originally Posted by roflwaffle

This is possible for automotive AC systems, but is there something about window units that won't allow me to do so? I definitely would need to evacuate/drain the system, install a low side tap-valve to charge it/add the R134a oil, and fix the leak it has now, but is there something about R22 designs that won't work with R134a?

Edit- I found this, which indicates that R134a would have a higher COP but lower "relative capacity", which presumably means that I would require more R134a to get the low side pressure up to spec compared to some other refrigerant because at some temperature the pressure of an equal amount of R134a is about half of that of R22. Unfortunately it doesn't mention anything about mechanical compatibility of R134a with R22 parts.

This thread has some information about changing refrigerants. Try searching through the thread for the info you want.

-AC_Hacker