I have a 2006 Mitsubishi Gallant that has an a/c leak from the evaporator. I added a dye and found the condenser leaking as well. I changed the A/C condenser since I had to change the radiator due to the engine overheating. I charged the A/C system and the system seems to work as it should until the evaporator becomes a block of ice. My question is why does the evaporator freeze up? If I shut it off for a few minutes and let it thaw out it works well, until it freezes up again. I know the evaporator is leaking, and I know I need to replace it. Why does it freeze up into a block of ice? -Don
Don, a partially charged a/c system can freeze up the Evaporator as you are describing. You stated the evaporator freezes up and it has to thaw out to work. This problem could also be the evaporator temperature sensor that shuts off the compressor when it sees the evaporator getting too cold and icing up. I suspect that the temp sensor is faulty is the main reason you are having this problem. The leaking evaporator may be the cause of this failing sensor due to it being contaminated with A/C compressor oil. The other area of concern is the Receiver drier that is installed in the A/C system to absorb any moisture in the system. Since this system has had leaks it has absorbed all the moisture it can absorb and the moisture that is circulating in the a/c system may have frozen the expansion valve in the open position.
I have mentioned several areas that can cause this problem. When the dash is removed to replace the leaking evaporator please test out the evaporator temperature sensor and replace the Expansion valve and drier. Please make sure this A/C system is put into a vacuum for at least an hour to help remove any moisture trapped in this closed a/c system after the new parts have been installed.
Years ago no one ever thought about fixing an a/c system in the wintertime. Now we know that a working a/c system helps clear foggy windows quickly helping the driver see better. So a good working A/C system is needed to operate a car safe in the summer as well as the winter.
If you would like, please call James Auto Center of Panama City for a free test drive and consultation about your A/C problem on your vehicle. All this costs is 15 minutes of your time and we can give you an idea of what will be needed to correct your A/C problem.