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Air Conditioning

Preventing Air Conditioning System Failures I

  • Never flush through the accumulator, receiver/drier, expansion valve, orifice tube, or compressor.
  • Never use any flush on R134a systems. (There are no approved flushes available for R134a systems. Use only R134a or ester oil to flush system.)
  • Never use dyes to test for leaks. (Use of dyes VOIDS ALL WARRANTIES - no original equipment manufacturer has approved ANY dye for use in A/C systems.)
  • Never re-use refrigerant recovered from an A/C system. Figure the cost of new refrigerant or known pure refrigerant into the repair work. (You can never be sure of what type of refrigerant was used in the system and re-using it could contaminate the repair. Mixing of R12, R134a, or blends will only lead to system failure.)
  • Never leave an A/C system open to the atmosphere. Keep lines and components securely capped. (This prevents moisture from gathering in system.)
  • Never recharge system with liquid refrigerant on suction side. (Compressors are designed to pump gas - not liquid. Pumping liquid refrigerant through compressor will destroy the compressor.)
  • Never install a compressor without first rotating it gently by hand five or six times. (This circulates any oil that may have accumulated in cylinder walls and prevents valve damage.)
  • Never replace compressor without replacing the clutch. (If the clutch is slipping it can overheat the compressor and cause the front seal to leak. Check voltage at clutch and check belt alignment.)
  • Never use air from an air compressor to remove excess flush or contaminants. (Most air compressors do not have the ability to remove moisture entirely from air. Use compressed nitrogen to avoid contaminating system.)
  • Never overfill the A/C system with oil. (A good rule of thumb is 8 to 9 oz. total of oil in an automobile A/C system. Overfilling results in slugging, reduced heat transfer, excessive high-side pressures, and reduced cooling capacity.)

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