Figure 6-60.Multiple-pass method of recycling.
The reprocessing of a refrigerant to original
production specifications as verified by chemical
analysis is called "reclaiming." Equipment used for
this process must meet SAE standards and remove 100
percent of the moisture and oil particles.
Most reclaiming equipment uses the same process
cycle for reclaiming refrigerant. The refrigerant enters
the unit as a vapor or liquid and is boiled violently at a
high temperature at extreme high pressure
(distillation). The refrigerant then enters a large,
unique separator chamber where the velocity is
radically reduced, which allows the high-temperature
vapor to rise. During this phase all the contaminants,
such as copper chips, carbon, oil, and acid, drop to the
bottom of the separator to be removed during the "oil
out" operation. The distilled vapor then leaves the
separator and enters an air-cooled condenser where it
is converted to a liquid. Then the liquid refrigerant
passes through a filter-drier into a storage chamber
where the refrigerant is cooled to a temperature of 38°F
to 40°F by an evaporator assembly.
COMPONENT REMOVAL OR
To maintain a refrigerant system at a optimum
operating condition sometimes requires removal or
replacement of some component. Procedures for
removal and replacement of some of the components
most often requiring action are covered in this section.
Removing Expansion or Float Valves
To help ensure good results in removing expansion
or float valves, you should pump the system down to a
suction pressure of just over zero. You should do this
at least three times before removing the expansion
valve. Plug the opened end of the liquid line and
evaporator coil to prevent air from entering the system.
Repair or replace the expansion valve and connect it to
the liquid valve. Crack the receiver service valve to
clear air from the liquid line and the expansion valve.
Connect the expansion valve to the evaporator coil
inlet and tighten the connection. Pump a vacuum into
the low side of the system to remove any air.