Automotive A/C Learning Center
DO THE JOB RIGHT, THE FIRST TIME
you need to know from the A/C Experts
Your compressor failed for a reason. There are two main
reasons why compressors fail. Number 2 is oil
starvation, where the system is not properly lubricated
and thus burns out. 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. 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.
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.
Pure R134 for R134 systems and retrofits. 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
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.
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
switches, sensors and/or a line manifold are necessary, use these
from the old unit.
Clutch/Pulley Turning Note:
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.
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
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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