Condenser

• The condenser collects filth and oil from the compressor. Refrigerant may carry this filth through the condenser to the expansion valve, clogging the valve or tube. Toyota recommends replacing the condenser if it is dirty. Flushing definitely moves sludge through the system. Sludge may block or damage the compressor. If you damage your air conditioner by flushing it, your air conditioner warranty is void.
  
  

Toyota Lexus

• Toyota Lexus parallel-flow air conditioners improved cooling, but they cannot be flushed because many tiny tubes that are only 0.04 and 0.06 inch in diameter are attached to them. Serpentine air conditioners flush well because there is only one path through the air conditioner. Toyota Lexus replaces the accumulator, orifice tube and expansion valve. Hoses with filters and mufflers must also be replaced.
  
  

Flushing

• Toyota Lexus only flushes the condenser. When flushing your air conditioner, install a filter on the liquid line to trap debris. Install a filter screen at the suction hose line on the compressor to trap debris blown from the compressor.
  
  

Sludge

• When sludge forms from moisture in the air conditioner reacting with lubricant and refrigerant in the condenser, corrosive acid forms. The corrosive acid makes pinholes in the evaporator and condenser from the inside, causing refrigerant to leak. Sealant may temporarily seal pinholes, but ultimately it passes through the system, causing more damage.
  
  

Chemical Flushing

• Flushing may be forcing air and flushing chemical through the condenser. Flushing takes 15 minutes by pressure washer at 50 psi over a catch pan. The condenser must dry for 45 minutes. Parts solvent, brake cleaner and de-greaser are too astringent. Acceptable solvents for flushing the condenser must be compatible with O-rings and seals. Good cleaners are HCFC-141B, ACC-U-Flush and Duraflush 141.