HOW TO PUMP THE REFRIGERANT BACK INTO THE RECEIVER:
Whenever it is necessary to open, or remove for repairs, the expansion valve, expansion coil, or the suction line, all the
refrigerant must be pumped back into the receiver and condenser, if it is to be used again after the repairs are completed.
The receiver and condenser will hold the entire charge of refrigerant.
Attach a compound gauge to the lowside or suction valve, and a pressure gauge to the highside or discharge shut-off
valve, purging the connections in the usual way. After the gauges are attached, turn both valves back one turn for
reading; now close the receiver valve to shut-off the receiver from the liquid line going to the expansion valve.
The next step is to start the compressor and run it until the compound gauge shows approximately 5 lbs. This operation
pulls the refrigerant all the way around through the system in the direction of the arrows shown in the diagram on the left,
and forces into the condenser and receiver.
When this pressure is obtained, it is reasonably certain that all the refrigerant is pumped back into the condenser and
receiver.
At this point, the unit can be stopped, and the highside shut-off valve closed to prevent any refrigerant vapor going back
into the compressor should the compressor valves leak.
Warning:
Never open a system on a vacuum as air will rush into replace the vacuum and will
probably draw some moisture into the system.
With the refrigerant back into the condenser and receiver, any part can be removed from the unit with the exception of the
highside shut-off valve, the condenser, and the receiver. These parts still have the refrigerant in them.