The laws governing the release of CFC’s and HCFC’s are not new and have been in existence since 1990. Releasing such into the atmosphere can result in heavy fines if any of the mandates are violated as per the Clean Air Act and the Technician page found on this site. Due to reprecussions that could follow specific step by step procedures have been established to recover, recycle and reclaim refrigerants. The recovery of refrigerant should only used DOT approved cylinders.
The cylinders used are painted yellow on the top part typically about 12 inches down the side. The rest of the body is found a gray color. The mandated on bottle filling which is set by the EPA is no greater than 80% of their liquid weight.
Recovery is known as the procedure of removing liquid or vapor refrigerant from a system and placing it into a separate, independent cylinder without any other requirements to be fulfilled ie: test or recycling of such. The recovery of refrigerants for a small sealed unit or appliance can be completed by several methods:
-Passive Recovery or System Dependent
Systems that have 15lb of refrigerant typically use the active method of recovery unless the system has a compressor that is no longer working. This method of recovery uses a self contained recovery unit that is certified for use by the Evironmental Protection Agency (EPA), Department of Transportation (DOT), and the Air Conditioning and Refrigeration Institute (ARI).
As mentioned previously mandates require that only 80% of the refrigerant must be removed from systems with the active method of recovery. There are many different types of recovery units for sale today and they all operate basically the same way. Always follow the recommended operation instructions for each unit be used and the method you are using. Almost all units today have common practices and features that use ports, gauges and valves as a way to purge refrigerant and other gases once removal of the refrigerant for a system is completed. The use of purging helps in not contaminating or mixing refrigerants which will cause trouble further down the road of the refrigerants.
Using vapor as a recovery method allows for vapor to be pulled out of a systems low side and discharges the refrigerant into a vapor recovery bottle as discussed above. Doing so requires hoses that connect to the systems low side and the units inlet valve. Another hose is placed between the unit’s outlet valve and the bottle’s vapor in valve. Almost all recovery processes recover via a liquid method (as much as possible) then switches over to the vapor method. This allows for the most recovery possible not to mention liquid recovery is much more quicker than using the vapor method saving you time, frustration and money.
When operating in a liquid recovery procedure, the use of the manifold gage high side valve is required. This is done due to allow the attachment of the liquid line from the system. When the liquid recovery is completed the gage valve on the high side valve is closed and the gage valve on the low side is now opened. This recovers refrigerant in the vapor state from the system.
The addition of filter driers will aid in the recovery process allowing you peace of mind that the refrigerant you have recovered is free from moisture. A sight glass also allows for monitoring during the process for which can indicate foreign material and/or moisture.
Universal Guidelines When Using a Recovery Unit Are Pretty Much Standard
-Make sure the recovery unit is purged from the previous operation
-Use only the same type of recovery bottle for each type of refrigerant
-Purge all hoses to remove air and non-condensable gases
-As a rule of thumb warmer conditions will allow for a more rapid recovery
-Filter driers and sight glass use will aid in prevent refrigerant contamination
-Only qualified personnel should operate recovery equipment
-Make sure that all maintenance is up to date on all recovery equipment
-Always observe proper PPE, Personnel Protective Equipment
-Use only DOT approved cylinders
-Well ventilated areas is a must
Remember that refrigerant is heavier than air and can fill your lungs. Its odorless and will produce phosgene gas if flamed. Always be careful and follow procedures when doing such.