6
Refrigerant Line Connections
IMPORTANT
This outdoor unit comes with a factory-installed
flowrator which is part of the service valve as-
sembly. The flowrator piston is located within a
connector tube (Figure 4) which is torqued to the
service valve body. It is imperative that the con-
nector tube is covered with a wet rag while braz-
ing to the service valve. Failure to properly cool
the connector tube while brazing could deform
the piston and affect system performance. If the
connector tube needs to be opened for service,
it must be torqued to 15.5-18.5 ft-lbs before the
system is charged with refrigerant. If the piston
is removed from the connector tube, it must be replaced in the direction shown in Figure 4 to ensure proper flow restriction.
To avoid overheating the service valve, TXV valve, or filter drier while brazing, wrap the component with a wet rag, or use a thermal
heat trap compound. Be sure to follow the manufacturer’s instruction when using the heat trap compound. Note: Remove Schrader
valves from service valves before brazing tubes to the valves. Use a brazing alloy of 2% minimum silver content. Do not use flux.
Torch heat required to braze tubes of various sizes is proportional to the size of the tube. Tubes of smaller size require less heat to
bring the tube to brazing temperature before adding brazing alloy. Applying too much heat to any tube can melt the tube. Service
personnel must use the appropriate heat level for the size of the tube being brazed. Note: The use of a heat shield when brazing is
recommended to avoid burning the serial plate or the finish on the unit.
1. The ends of the refrigerant lines must be cut square, deburred, cleaned, and be round and free from nicks or dents. Any other
condition increases the chance of a refrigerant leak.
2. “Sweep” the refrigerant line with nitrogen or inert gas during brazing to prevent the formation of copper-oxide inside the
refrigerant lines. The POE oils used in R-410A applications will clean any copper-oxide present from the inside of the refriger-
ant lines and spread it throughout the system. This may cause a blockage or failure of the metering device.
3. After brazing, quench the joints with water or a wet cloth to prevent overheating of the service valve.
4. Ensure the filter drier paint finish is intact after brazing. If the paint of the steel filter drier has been burned or chipped, repaint
or treat with a rust preventative. This is especially important on suction line filter driers which are continually wet when the
unit is operating.
NOTE:
Be careful not to kink or dent refrigerant lines. Kinked or dented lines will cause poor performance or compressor damage.
Do NOT make final refrigerant line connection until plugs are removed from refrigerant tubing.
NOTE:
Before brazing, verify indoor piston size by checking the piston kit chart packaged with indoor unit.
Leak Testing (Nitrogen or Nitrogen-Traced)
Pressure test the system using dry nitrogen and soapy water to locate leaks. If you wish to use a leak detector, charge the system
to 10 psi using the appropriate refrigerant then use nitrogen to finish charging the system to working pressure then apply the
detector to suspect areas. If leaks are found, repair them. After repair, repeat the pressure test. If no leaks exist, proceed to system
evacuation.
System Evacuation
Condensing unit liquid and suction valves are closed to contain the charge within the unit. The unit is shipped with the valve stems
closed and caps installed.
Do not open valves until the system is evacuated.
CHAMFER SIDE OF PISTON
THIS DIRECTION
VALVE
PISTON
CONNECTOR
COMPONENT
Figure 4
Exploded Top View of Service Valve with Piston and Connector Tube Component
Summary of Contents for RR20AVAK9
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Page 25: ...25 APPENDIX LONG LINE SET APPLICATION R 410A ...
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Page 49: ...13 ا ً د عم فارغة ُركت ت الصفحة هذه ...
Page 59: ...23 والصيانة الخدمة ...
Page 61: ...410A R التكييف ألجهزة الطويلة الوصالت مجموعة استعمال الملحق 25 ...