I have a Norcold 1200 LM 4 door refer. I just took it to a RV repair shop In San Diego for the second time. The problem is the freezer makes ice and keeps most things frozen but the refer won't get below 42 degrees on AC. It's worse on gas. I asked the guy that checked me in if they check the gas pressure measuring inches of water (manometer. Didn't know what I was talking about. I have replaces the circuit board (Dinosour)twice now (OEM)and nothing has changed. We can't keep food from spoiling. I keep the refer plugged in all the time when home. I took off the cover to the vent to check the air flow and all is clear. Both muffin fans work quite frequently. Is there a way to check if the cooling unit is partially clogged? The last bill was just over $600 dollars. I am quite frustrated at going to different shops to find out they really don't know much about refers. Help needed in San Diego. Hikenbike