Long story short, we did a house rewire this summer, ac was present and had a mca of 18 and mop of 30. Disconnect basically on the back side of panel, #12 was installed from panel to disconnect and a 30 was installed. House has been put on the market and potential buyers brought there H.I. before closing, of course the #12 on a 30 amp is a death blow to the deal unless the #12 is upgraded to #10. My response is go pound sand and here are the code articles that support my wiring methods, further more call the city inspector and they will tell you the same thing. H.I. has sought the advice of another electrician and a electrical engineer, major violation and the house will burn down is there response, city inspector follows suit claiming the same violation. Seller ask me to change the wire and send him the bill, just to complete the sale, we did, and noted on the invoice original wire was code compliant. Call to the city inspector the following day and a short conversation on code articles and why this is allowed was all that was needed with him. Would you pursue a discussion with the H.I. on this matter and hope he understands, or just move on and spend your energy elsewhere? We may have to deal with various H.I. 2 to 3 times a year