In the early days, though (mid-1980s), almost everybody was making such machines and the quality varied — to say the least.
Now the laws of supply and demand have reduced the manufacturers to, for the most part, a few familiar and long-standing names. And the technology has also become more understood and reliable.
At the same time, each new generation of equipment has the latest in technological innovations.
Technicians want it all in recovery equipment — small size, reasonable price, and powerful push-pull — and in one unit. While such an ideal machine is not possible (there are laws of physics, you know), manufacturers haven’t given up trying to move more and more in that direction.
One example of new technology comes from RefTec Inter-national of Clearwater, FL. The company’s MicroVac oilless recovery machine weighs in at less than 30 lb and comes with a shoulder strap.
The unit is said to have built-in anti-slugging protection. Tech-nology includes a horizontal expansion chamber in the compressor head, where refrigerant is automatically flashed and vaporized before being drawn into the compression cylinder.
According to the company, “The units have capillary tubes to automatically regulate refrigerant liquid through the compressor at its optimum flow rate.”
The company went on to say, “Other units either drop incoming liquid directly on top of the intake valve or receive it through the compressor crank case. These designs rely on the technician to manually regulate refrigerant flow to prevent compressor damage.”
The company cites statistics from the ARI Directory of Certified Refrigerant Recovery/Recycling Equipment/740, showing that the MicroVac unit has a direct liquid recovery rate of 3.80 lb/min for R-22 and 4.38 lb/min for R-410A.
The fact that there is a listing for R-410A is another new sign of the times. R-410A is an HFC refrigerant being touted as a long-term alternative for R-22 due to the phaseout of HCFCs. More and more unitary manufacturers are introducing R-410A in air conditioning applications. HFCs are included in EPA regulations for refrigerant recovery.
RefTec does warn technicians that “Due to extremely high pressure, R-410A is the most difficult refrigerant to recover.
“To do a good job, a recovery unit must have high condensing capacity to remove adequate heat from recovered refrigerant and keep tank pressure down. On direct liquid, the unit must readily handle the incoming stream of high-pressure liquid.”
For more information, contact RefTec at 800-214-4883; www.reftec.com (website).
Publication date: 05/14/2001