Procedure we follow when flushing a system to remove debris and oil form an automotive air-conditioning system.

1. Each individual component needs to be flushed separately. Removal of hoses or any other devices may be needed for proper flushing.
2. Flush system with either an A/C flushing agent or products such as Mineral Sprits, Flush Solvents and Paint Thinner careful with Paint Thinner for obvious reasons. You may even purchase a Flush Gun or for the professional the Hecat Professional Flush Equipment to help get the flushing agent through the components correctly. After using the flushing agent use compressed air to blow any residue left behind from the flushing process. It also helps to place you finger or a shop rag on the opposite end to create some back pressure to dislodge any debris. It's best to perform this procedure many times in both directions to achieve the cleanest system possible. When you think its clean do it again you can never have a clean enough system. Some condensers are very difficult to flush properly and may need to be replaced. Cheaper replacing them than to have debris left in the system and damage the new components.

3. Do not flush any of these components accumulator/drier, compressors, expansion valves/orifice tubes and any hose assembles the have either a muffler or filter attached to them. These items need to be replaced.

4. Our company will use Nitrogen after the flushing stage as a finial flush to remove any moisture that maybe left behind by the shop air.

5. At this point you are ready to replace the damage components along with the correct oil and have system evacuated and recharged. Evacuation of the system should be done for a minimum of 30 minutes to one hour. Charging capacities very from vehicle to vehicle. So it is best charge to OEM listed capacity when available! Conversions can be changed by pressures trying to achieve as close to the OEM R12 capacity without creating a high pressure issue. Complete set of refrigerant gauges is needed for this as you will need both low and high side pressures to perform these tasks