For those still interested - The AC contractor wanted me to do another test while recording the temp. going in (coil inlet) the wall unit. So I did that, see graphic.
Also, I called Mitsubishi again - got transferred to customer relations. The lady that answers that line knows me now. :-) Basically the only option is to continue trying to work with the contractor that installed the system. If they need help they can contact Mitsubishi or their distributor that administers the Diamond Contractor program. The distributor is supposed to have experts that advise or can come on site. The other thing she mentioned a few times.... if I don't have confidence in the original contractor get another licensed AC tech to come and take a look. Certainly not a bad idea but not happy to pay for install and fix labor coverage and then have to go to another company to get a diagnosis.
Anyway here is the last test.
