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Robinair 15600 is the industry standard.
The most common air conditioning vacuum pump is the Robinair 15600. This versatile vacuum pump is a 6 cfm, 2 stage vacuum pump that is most often found in the automotive service shops. For the professional automotive shop, the 6 cfm is minimum size vacuum pump you need. This size can handle vehicle air conditioning systems ranging from a car all the way to buses and RVs. The Robinair 15600 has the cfm to removc moisture and air from most vehicle air conditioning systems. This unit has the power reach a 600 micron vacuum in under 60 minutes on most air conditioning systems. A weaker unit takes more than twice that amount of time. Also, the latest A/C systems are built to much tighter specifications and getting a good solid vacuum has never been more important. The reason is the modern systems are far less tolerant to contaminants and moisture build up and this can cause long term damage. If moisture builds up in the lines, it can crystallize at expansion points in the air conditioning system. This is why pulling a good vacuum is critical. A good solid vacuum in the system will evaporate the moisture and prevent "freeze up". Moisture causes many other problems. High moisture levels combined with refrigerants is very corrosive to air conditioning systems. You will not notice the effects of corrosion until its done some serious damage.
The Robinair 15600 is a good investment
It may be tempting to use an inexpensive Venturi type vacuum pump. This type a vacuum pump works off of shop air to produce a vacuum on an air conditioning system. They are cheap and relatively easy to use. However, they will not pull a proper vacuum and they leave damaging moisture behind. The Robinair 15600 vacuum pump is a 2 stage model that runs off of 110 volts. The 2 stage rotary design and high cfm rating on the 15600 insure you will get the required 600 microns of vacuum. (It can achieve this under 60 minutes saving you time as well.) Venturi type vacuum pumps are really made for the home garage mechanic and professional air conditioning service techs do not use them. A good 2 stage vacuum pump will pay for itself over time and produce far better results.
Robinair produces vacuum pumps with lower cfm ratings and they may be fine for your particular application. All of the Robinair vacuum pumps are 2 stage and built to the industry's highest standards. But if your operating a automotive service shop or maintain a varied fleet of cars and trucks, the Robinair 15600 should have you covered for most air conditioning systems.
