Brazing Recommendations; Brazing Procedure; Figure 19: Brazing - Sectional View; Figure 20: Suction Tube Brazing Areas - Emerson Copeland EazyCool ZXDI Series Application Manuallines

3.3.2 Brazing recommendations

IMPORTANT
Blockage! Compressor breakdown! Maintain a flow of oxygen-free nitrogen
through the system at very low pressure during brazing. Nitrogen displaces
the air and prevents the formation of copper oxides in the system. If allowed
to form, the copper oxide material can later be swept through the system and
block screens such as those protecting capillary tubes, thermal expansion
valves, and accumulator oil return holes.
Contamination or moisture! Bearing failure! Do not remove the plugs until
the compressor is set into the unit. This minimises any entry of contaminants
and moisture.
▪
Remove the discharge connection cap.
▪
Remove the suction connection cap.
▪
Open both valves mid-way. Care should be taken to avoid the holding charge releasing too
quickly.
▪
Be sure tube fitting inner surface and tube outer surface are clean prior to assembly.
▪
Both tubes are extended from the condensing unit housing, therefore we recommend to
isolate the housing by using a wet cloth on the copper tubing.
▪
Recommended brazing materials: a copper/phosphorous or copper/phosphorous/silver
alloy rod should be used for joining copper to copper whereas to join dissimilar or ferric
metals a silver alloy rod either flux coated or with a separate flux would be used.
▪
Use a double-tipped torch.
Figure 19: Brazing – Sectional view

3.3.3 Brazing procedure

For brazing of the tubes, please refer to Figure 20 and procedure hereunder:

Figure 20: Suction tube brazing areas

▪ Then heat area 3. This will draw the brazing material down into the joint.
NOTE: The time spent heating area 3 should be minimal. As with any brazed joint,
overheating may be detrimental to the final result.
C6.1.10/0118-0318/E
▪
Fit the copper tube into the unit tube.
▪
Heat area 1. As the tube approaches brazing
temperature,
▪
Heat area 2 until braze temperature is attained.
It is necessary to heat the tube evenly. Move the torch
up and down and rotating around the tube.
▪
Add braze material to the joint while moving the
torch around the joint to flow braze material around the
circumference.
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