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AC Installation

AC Installation

Air Conditioning Installation Tips To Do The Job Right The First Time

Flush and Vacuum

Your compressor failed for a reason. There are two main reasons why compressors fail. The number 1 reason is contamination in the system. Cleaning out this contamination is crucial to ensuring that the new compressor is not also contaminated. Number 2 is oil starvation, where the system is not properly lubricated and thus burns out. We require every system to be properly flushed and vacuumed.

We recommend flushing the system and vacuuming, then inspecting what comes out through a coffee filter for discoloration or metal flakes. Always flush and evacuate before changing parts. Always use A/C system flush solvent. If it is not perfectly clean after the flush and vacuum, we recommend re-flushing the system. If it is still not perfect, then we recommend replacing the condenser and possibly other parts such as hoses or the evaporator. Do not bother flushing a third time. Many newer vehicles have serpentine or parallel flow condensers that simply cannot be properly cleaned and must be replaced at this point.


AC Oil

Oil is crucial to a properly functioning A/C system. It is crucial to use a high quality oil to ensure that it will not break down over time. Remember the number 2 cause of compressor failure is oil starvation, often from the oil decomposing over time. That decomposed oil can often be the cause of the debris in a contaminated system. We recommend a double end capped PAG oil or better. Check the book for the proper viscosity. Oil comes as 46, 100 or 150 viscosity. You will need the correct type for your vehicle, they are not interchangeable and higher is not better. Each compressor is designed to work with certain oil.

Many of our compressors come pre-filled with oil. We can never guarantee that the oil is the correct amount. Most manufacturers put just a few ounces of oil in for testing and shipping. We can also never guarantee the quality of that oil, or how long the oil has been in there. Oil exposed to atmosphere can expedite the breakdown process. Therefore, we recommend dumping all oil and starting with a sealed bottle of premium oil. Do your own measuring to ensure the job is done properly. Also check the specifications book; many manufactures want half oil in the compressor and half in the drier, some want all in the compressor. Don't guess, follow the instructions.


Freon/ Refrigerant

Use only pure R134 for R134 systems and retrofits and pure R12 for R12 systems. No exceptions.

There are a ton of 'Freon/ Refrigerant alternatives' out there. The bottom line is that none of those have been tested to work with the seals and gaskets inside our compressors. We can therefore not warranty our parts when you use these products. Ensure that you are only using refrigerant from a sealed, trustworthy source. Be careful, there are many of fraudulent products on the market.



The drier is the filter on the A/C system. Some vehicles have an accumulator and some have a receiver drier, but either way the internals do the same thing. A new drier is required every time you change the compressor, no exceptions. Inside a drier is a desiccant element that pulls moisture and debris from the system. Remember that moisture from water is very bad, it alters the viscosity and can ruin a system.

Just like you wouldn't change your engine oil without changing your oil filter, the same is true on A/C systems. You want that drier cleaning your system to ensure long lasting performance. You definitely do not want that old drier dumping debris back into the system.



Most modern A/C systems use O-Rings at every connection. Half of all A/C leaks turn out to be wrong, bad or improperly installed O-Rings. We recommend that O-rings be changed with the compressor. We recommend that as you remove an O-ring, that you tape it to a piece of paper and note next to it where it came from. This way if you have a problem in that area later, you can double check that you used the correct O-ring.


Expansion Device

The expansion device is a generic term. It can be an orifice tube, expansion valve or expansion block. An orifice tube should always be replaced, it should never be cleaned. An expansion valve or block is a little more difficult. They should always be removed and inspected or replaced during a repair. A stuck expansion device can allow too much pressure to build in a system and thus blow out the head of the compressor.

The rule of thumb is that if you are replacing the compressor because it is leaking or not blowing cold enough, then cleaning is acceptable. Any other failure requires a new expansion device. If unsure, it never hurts to change the expansion device.


Electrical Connections Note

We make every effort to supply all compressors with the appropriate electrical connections. However, it is possible that the connector on our compressor could be different that your application. Most new compressors are also supplied without a connector. If this is the case, you may cut the wire in order to use your connection WITHOUT affecting your warranty. We recommend using wire nuts secured with electrical tape for these connections.

Most compressors are shipped without switches or sensors. If switches, sensors and/or a line manifold are necessary, use these from the old unit.


Clutch/Pulley Turning Note

All compressors are bench tested at standard RPM's, However, all compressors MAY NOT ALWAYS turn by hand! Many popular compressors (including H6 Series GM) will NOT turn by hand. Do not force it.



Enclosed and on our website you will find our full warranty. While our warranty gets into extensive detail, the important thing to understand about it is that it is crucial to do the job properly. The A/C system is one of the most powerful, violent and difficult systems in the vehicle. Trying to cut corners will result in a system failure. Even if you think it is "just the clutch," there is no excuse for not doing the job properly.

The first thing we will ask if you have a problem is to prove the above items were done properly by faxing over the receipts. We require this, because we know that if you do the job properly, you will probably have no problems at all.

We want your A/C to be working better than ever. Please feel free to contact us with further questions. Please note, however, that while our techs are the best in the business they simply cannot give vehicle specific information. They will often direct you to the guide book for your car for specific questions.


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