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Too charge or not to charge, that is the question?

It is getting warm outside and your cars a/c system is letting you know if it is not working like it should. One of the a/c first symptoms to you know something is not right is inadequate cooling of the passenger compartment. You take it to your local auto repair shop and they “top off” the a/c system. In a few weeks you’re a/c compressor starts to make noise and the vehicle is not as cold. The sad truth is that in today’s vehicles “topping off” an a/c system is the “Kiss of Death” to a compressor and possibly the condenser. Today’s cars a/c systems have “tight” tolerances to the amount of refrigerant needed to keep the compressor from failing. As little as 10% too much or too little refrigerant may destroy you’re a/c compressor in just a few months. This amount can be less than one ounce in some vehicles. Too little refrigerant will starve the compressor from receiving oil needed to keep the moving parts inside the compressor lubricated. Too much refrigerant will cause excessive pressure making the compressor work too hard and burn up needlessly. So you ask, what is the correct way to charge up my a/c system so that I won’t destroy my a/c compressor? The answer: proper equipment and updated repair procedures and training is needed and required. Times have changed, today’s passenger vehicles have tiny little a/c compressors that use around 1 pound of refrigerant, compared to the 3 and 4 pounds of refrigerant that we used to use. This is why 10% over charge or undercharge of an a/c system can destroy you’re a/c system. This tiny amount is impossible to determine using only pressure gauges and experience. This type of recharging you’re a/c system is why people continue to have a/c problems after using the above described method. The correct charging procedure that the automotive engineers have developed is as follows: 1) Remove the old refrigerant and measure how much oil and refrigerant was removed. 2) Then replace the amount of oil that was removed. 3) Recharge within one gram the PRECISE amount of refrigerant that is required by the manufacture for your specific vehicle. By following this procedure you are insuring that your high dollar compressor and a/c system is not being destroyed. This proper recharging method take’s about an hour and a half of time to do. This requires expensive and federally approved equipment that repair shops HAVE to purchase to be compliant with the EPA and DEP. (Does this ring of un-funded mandate?) Unfortunately this is not the $19.95 repair that we used to see in the recent past. The good news is that the money you pay now to do it correctly will save you hundreds by the end of summer. It is like the old TV commercial during the 70’s. Pay a little now to prevent a problem, or pay a lot later. Live long and prosper.


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