Late Model Condensers Cannot Be Flushed (Only Replaced)
The parallel flow condenser is by far the most efficient condenser to use with R134a refrigerant. The multi-channel construction and multiple passes the refrigerant makes through the condenser allows maximum heat transfer. The smaller tubes and wide surface area allows the most refrigerant to come in contact with air flowing through the condenser fins.
The reasons for this efficiency is also one of its major drawbacks. These small tubes that efficiently transfer heat are so small that they trap any contamination in the system that tries to pass through them. Flushing will not remove the contamination from the condenser. This contamination will create a restriction in the condenser and make the high side pressures go up. This forces the compressor to work harder and possibly fail. Contamination in the condenser can also work itself free and end up at the compressor where it will also cause a failure.
If there is a situation where the system needs to be flushed we strongly recommend changing the condenser. This will cut down on comebacks and also will help extend the life of the AC system.