too far into the drier and contacting the screen. To facilitate the installation, place a slight bend in
the capillary tube about 3/4inch from the end and insert into the drier. Remove the process tube
adapter from the condenser outlet and prepare the tube for connection to the drier inlet. The drier
inlet joint will be the only copper-to-steel connection which will require the silver solder and flux.
To help prevent flux from entering the system, first insert the line from the condenser into the
drier inlet, then apply the flux. Braze both the inlet and the outlet joints of the re-placement drier.
3. Isolate and flush the remainder of the system
Score and break the suction line close enough to the old compressor to be able to reconnect it to
the replacement compressor later. Attach a process tube adapter to the evaporator side of the
suction line. Connect the hand valve and hose from the recovery equipment to this adapter. Be
certain that the pressure in the charging cylinder is about 30 p.s.i.g. above ambient temperature.
Start the recovery unit and open the hand valve to the suction line. Release four (4) ounces of
R134a from the charging cylinder into the system. It will take about 15 minutes for the refrigerant
to pass through the condenser, hot pipe, filter drier, capillary tube, evaporator, suction line and
into the recovery system. This 15 minutes time can be utilized to remove the old compressor and
prepare the new compressor by mounting into place and wiring electrically. Remember to leave
the plugs in place until brazing.
4. Complete compressor replacement
Close valves to the recovery system. Re-move process tube adapters from both the suction and
discharge lines. During final flush, remove old compressor, and install replacement compressor
leave plugs in place until brazing. Connect and braze suction and discharge lines to the
replacement compressor. You are now ready to add the temporary piercing valve to the drier
process line and proceed with the sweep and final charging of the system.
CAUTION:
In order to prevent sealed contamination, the time of atmospheric exposure must be
limited to 15 minutes. Do not pull the plugs from the new compressor until you are ready to make
the connections.
5. Sweep and Final Charge
The sweep charge is a method of purging the sealed system of moisture, air and potential
contaminants. Also during this procedure, the system may be checked for leaks before the final
charge. If this procedure is followed as outlined, it will allow for the capture of 90-95 percent of
the available refrigerant, thereby ensuring that the system will operate as designed. The sweep
procedure for R134a refrigerant systems is made after the system has been repaired and/or
flushed. Three (3) ounces of refrigerant R134a is added to the system, circulated by the
compressor for 5 minutes and recovered. Since a new filter drier has already been installed, a
high side process tube is available. Install a temporary access valve to this process tube close
enough to the end of the tube so that the tube can be pinched closed behind the valve and the
opening sealed shut after the valve is removed. Remember, no access valve is to be left on the
sealed system. Connect a 1/4 inch flare tee to the access valve. Connect a quick coupler hand
valve to each side of the tee. To one hand valve, connect the hose from the charging cylinder.
To the other valve, connect the hose to the recovery system. The following steps take you
through the sweep and final charge.
Step 1.
Set up of valves: temporary access valve (C) piercing drier process tube, connected
to flare tee, hand valve (A) to charging cylinder, hand valve (B) to recovery system.
Step 2.
With liquid refrigerant present to valve A, valve B closed and valve C open(C will
