Refrigerant recovery machine
Since the early 1990s, all service techs are required to recover all refrigerants before opening a system for repair or disposal.
Refrigerants could no longer be dumped into the atmosphere. The refrigerant must be removed and stored in a cylinder. It could be reused without recycling in equipment owned by the same owner but could not be reused in equipment owned by another customer.
What this means for the service tech is, recover the refrigerant into a cylinder and when the cylinder is filled, the refrigerant can be returned to a licensed reclaim company to be reclaimed for use as new refrigerant.
To do this you will need a recovery machine. This machine is designed and approved for use as a recovery machine.
There are a number of approved designs but all of them are much the same as a an air conditioning condensing unit.
They will have a compressor, a condenser, both high and low pressure gauges and appropriate valving.
Below is an introductory video of an approved recovery machine.
Refrigerants could no longer be dumped into the atmosphere. The refrigerant must be removed and stored in a cylinder. It could be reused without recycling in equipment owned by the same owner but could not be reused in equipment owned by another customer.
What this means for the service tech is, recover the refrigerant into a cylinder and when the cylinder is filled, the refrigerant can be returned to a licensed reclaim company to be reclaimed for use as new refrigerant.
To do this you will need a recovery machine. This machine is designed and approved for use as a recovery machine.
There are a number of approved designs but all of them are much the same as a an air conditioning condensing unit.
They will have a compressor, a condenser, both high and low pressure gauges and appropriate valving.
Below is an introductory video of an approved recovery machine.
The refrigerant recovery cylinder is a reusable refrigerant container that is connected to the recovery machine to accept liquid refrigerant as condensed by the recovery machine.
The cylinder must be capable of handling the pressure of the refrigerant being recovered. The cylinder in the video below is capable of 400 psi which will work for all refrigerants with a pressure as high as R-410A.
There are 2 valves on top of the cylinder. One will allow liquid and one will allow gas to be removed from the cylinder.
The color code of the valves is not indicative of which valve it is as different brands reverse the colors.
When using the cylinder as a receiver for refrigerant, either valve may be used.
Only one type of refrigerant may be placed in the cylinder.
If refrigerants are mixed in the cylinder, the refrigerant must be destroyed by an accredited facility. They will charge a pretty penny to destroy it.
The cylinder can only be filled to 80% of its capacity. There are 2 ways to do this.
One, you can use a float device installed on the cylinder and connected to the recovery device if equipped.
Two, and the more common way, is to weigh the empty cylinder to obtain a Tare weight.
Then, multiply the rated capacity of the cylinder by .80.
Add the modified capacity to the tare and mark it on the cylinder.
When the cylinder is new, it is charged with nitrogen. This gas must be evacuated with a vacuum pump.
The video below describes the procedure to commission a new cylinder.
The cylinder must be capable of handling the pressure of the refrigerant being recovered. The cylinder in the video below is capable of 400 psi which will work for all refrigerants with a pressure as high as R-410A.
There are 2 valves on top of the cylinder. One will allow liquid and one will allow gas to be removed from the cylinder.
The color code of the valves is not indicative of which valve it is as different brands reverse the colors.
When using the cylinder as a receiver for refrigerant, either valve may be used.
Only one type of refrigerant may be placed in the cylinder.
If refrigerants are mixed in the cylinder, the refrigerant must be destroyed by an accredited facility. They will charge a pretty penny to destroy it.
The cylinder can only be filled to 80% of its capacity. There are 2 ways to do this.
One, you can use a float device installed on the cylinder and connected to the recovery device if equipped.
Two, and the more common way, is to weigh the empty cylinder to obtain a Tare weight.
Then, multiply the rated capacity of the cylinder by .80.
Add the modified capacity to the tare and mark it on the cylinder.
When the cylinder is new, it is charged with nitrogen. This gas must be evacuated with a vacuum pump.
The video below describes the procedure to commission a new cylinder.
Once you have assembled the gauge set, recovery machine and the recovery cylinder at the system to be recovered, recovery can be started.
Below is a video describing the operation of recovery.
Below is a video describing the operation of recovery.
I have used recovery machines from the first date we were required to use them. In those early years, recovery machines were dying like flies. We seldom could keep one from failing for more than a few months.
One of the primary failures we had was recovering liquid. Most compressors used in recovery machines were similar to refrigeration compressors. These compressors do no tolerate liquid. As refrigerant is often liquid when coming out of the system being recovered, the compressors were damaged by the liquid. In future machines, some of this weakness was fixed.
However, these machines are still damaged by liquid slugging. So, whenever possible, recovering refrigerant from a unit with an operating compressor, you can assist the recovery and hopefully save your machine by recovering the initial liquid from the system by using the system compressor.
Because every A/C outdoor unit is a condensing unit, you can attach a recovery cylinder to the liquid line and start the unit. The high side pressure will exceed the saturated pressure in the recovery cylinder and the condensed refrigerant will flow into the cylinder.
This will not remove all the refrigerant from the system, but will reduce the liquid to a very low level. Once the weight on your scale stops increasing, you can proceed with the rest of the recovery.
The video below covers how to do this operation.
One of the primary failures we had was recovering liquid. Most compressors used in recovery machines were similar to refrigeration compressors. These compressors do no tolerate liquid. As refrigerant is often liquid when coming out of the system being recovered, the compressors were damaged by the liquid. In future machines, some of this weakness was fixed.
However, these machines are still damaged by liquid slugging. So, whenever possible, recovering refrigerant from a unit with an operating compressor, you can assist the recovery and hopefully save your machine by recovering the initial liquid from the system by using the system compressor.
Because every A/C outdoor unit is a condensing unit, you can attach a recovery cylinder to the liquid line and start the unit. The high side pressure will exceed the saturated pressure in the recovery cylinder and the condensed refrigerant will flow into the cylinder.
This will not remove all the refrigerant from the system, but will reduce the liquid to a very low level. Once the weight on your scale stops increasing, you can proceed with the rest of the recovery.
The video below covers how to do this operation.
Maintenance of the recovery machine is simple and easy to do.
When I have shut off the recovery cylinder valves, I remove the recovery machine to recovery cylinder hose from the cylinder. I use brass caps on both outlets on the recovery cylinder to keep the valves clean.
The hose I removed from the cylinder is connected to the inlet of the recovery machine. This covers both the inlet and the outlet of the machine.
To remove the air from the line, open the outlet valve to pressurize the hose. Then crack the hose at the inlet to bleed the air out of the hose.
With that, the machine is prepared to do the next operation.
The video below demonstrates this operation.
When I have shut off the recovery cylinder valves, I remove the recovery machine to recovery cylinder hose from the cylinder. I use brass caps on both outlets on the recovery cylinder to keep the valves clean.
The hose I removed from the cylinder is connected to the inlet of the recovery machine. This covers both the inlet and the outlet of the machine.
To remove the air from the line, open the outlet valve to pressurize the hose. Then crack the hose at the inlet to bleed the air out of the hose.
With that, the machine is prepared to do the next operation.
The video below demonstrates this operation.