Vacuum Pump

In our day-to-day support work, refrigeration technicians come to us time and again who need advice on choosing the right vacuum pump for you. In this blog post we would like to give you an overview and a small purchase decision aid. Of course, we cannot go into all eventualities and special cases in one post, so we recommend: If you are not sure which pump is the right one after reading this article, contact us directly by email or phone. We are happy to help.

The Starting point

After vacuum pumps could only be obtained from European brand manufacturers in reasonable quality for decades, this market has also been flooded with products from the Far East in recent years. Some are of usable quality, others are not even worth the few euros that such a Chinese pump still costs.

Just as VW, Mercedes and Porsche have their right to exist as brands, the tool manufacturers at the upper and lower end of the price spectrum also have their right to exist. Whether you choose Refco, Mastercool, CPS, Value or another manufacturer depends on your situation, your preferences and your intended use. The best way to find out what is right for your individual needs in a conversation with our support. Just this much: all pumps in our shop are of a quality that we would use and recommend ourselves. There are no cheap throw-away tools with us.

Refrigerant

Not every vacuum pump is equally suitable for every refrigerant. The majority of the pumps can be used variably for the majority of all refrigerants, but new refrigerants such as R32 or R1234YF in particular bring new properties with them. Many of the new refrigerants are partially flammable, which requires vacuum pumps and other tools used to be prepared accordingly. So ask yourself which refrigerants you want to use the pump for now and in the future and choose the pump accordingly. It makes more sense to spend a few euros more on a pump that is also suitable for new refrigerants than to have to buy a new one in a few months.

Power

The performance of vacuum pumps for refrigeration technology is usually given in Germany in liters per minute, l / min. American manufacturers also like to quote "CFM", cubic feet per minute. The conversion is relatively easy, one CFM corresponds to approx. 28.32 l / min. Liters per second or cubic meters per hour also appear occasionally.

The following table gives an overview of common services and suitable areas of application. Depending on whether the evacuation process should proceed faster, a higher output can of course always be selected. The information is only an approximate recommendation.

Ultimate vacuum

The lower the ultimate vacuum the pump can achieve, the better the pump can eliminate moisture from the system. A basic distinction is made between single-stage and two-stage vacuum pumps. We only recommend single-stage pumps for occasional use in the area of simple split systems, small household refrigerators or in the area of car air conditioning. For everything that goes beyond a rare use in this area, we recommend two-stage pumps. These achieve a lower ultimate vacuum and thus a better drying performance.

For the professional use of a vacuum pump, we recommend ultimate vacuum values of 15-30 microns. As already shown, the following applies here: the lower, the better.

Connections

When choosing your pump, make sure it has all of the connections you will need. 1/4 "SAE is standard, we also recommend a 5/16" SAE connection for R410A systems. Depending on the size of the pump, a 3/8 "connection makes sense if you have the appropriate hoses and connections on your manifold. With a 3/8" you can evacuate faster.

Furnishing

We definitely recommend using a vacuum pump with a solenoid valve to prevent the oil from the vacuum pump getting into the refrigerant circuit.

In many cases, a torr meter (vacuum meter) directly on the pump is also useful in order to be able to measure the vacuum directly. So you don't need an external vacuum meter.

The weight of the pump should also be taken into account in your purchase decision. You have enough to haul, in addition to all the other tools and the 25 kg pump that sucks up 1000 l / min to lift up to the third floor to evacuate a split system there, makes neither sense nor fun.

Maintenance and Operation

Note that a vacuum pump designed for refrigeration and air conditioning is never designed for continuous operation. Any misuse of a vacuum pump, for example for laboratory or production purposes, is therefore never covered by the guarantee. For such purposes there are special manufacturers of industrial vacuum pumps for continuous operation.

You should also always ensure that the vacuum pump is filled with sufficient oil. This can usually be seen on the oil sight glass on the front of the pump. The oil must be changed regularly.

Buy Recommendations

As already mentioned, it is difficult to make general recommendations as this depends on your individual requirements. Generally recommending WHAT to buy is therefore problematic. But of course we can tell you WHERE to buy it: from us :-)

Here is the link to our vacuum pumps category, here you will find our complete range:

Vacuum Pumps at Kaeltetechnikshop.com

Here also our bestseller, a 2-stage Vacuum Pump from Value with a solenoid valve and vacuum meter on the pump and with a performance that is sufficient for most of all applications:

Value Vacuum Pump

Please do not hesitate to contact us if you have any questions. We are looking forward to your contact!