After looking at the rules, I'm not sure if I broke #3. Let me rephrase just in case. In a split system, like the one described, (a) is there a reasonably simple test that can be performed to determine that the solenoid valve at the evaporator is defective and that is causing the icing? (b) would it be reasonable to expect a tech to perform such a test early on in the diagnosis stage? and (c) is icing caused by a failed evaporator solenoid valve an obscure or rare problem? Thanks.