TM 9-4120-404-14
(5) Apply sufficient heat uniformly around the joint to quickly melt the filler alloy. If heat is applied slowly, or
only on one side, the entire component or length of tubing will be heated and filler alloy in adjacent joints may also be
melted. Remove heat as soon as the joint separates.
d. Cleaning debrazed joints. All filler alloy must be cleaned from debrazed joints before reassembly. Heat each
piece of the joint until the filler alloy is melted and then wipe it away with a damp cloth. Be sure no filler alloy or other
debris are left inside any tubing, fitting, or component.
e. Reassembly. If tubing sections or fittings were removed with a component, debraze them from the component,
clean the joints, and braze them to the new component before reinstallation.
f. Brazing. Braze joints within the air conditioner as follows:
(1) Position the component to be installed.
(2) To prepare a joint on a valve for brazing, disassemble the valve to the extent possible. Then apply heat
sink to all nearby surfaces but the joint. (If heat sink is not available a wet rag may be used).
(3) Protect insulation, wiring harnesses, and surrounding components with appropriate shields.
(4) Be sure the work area is well ventilated and that dry nitrogen is flowing through the refrigeration system at a
rate of 1 to 2 psi.
(5) Apply sufficient heat uniformly around the joint to quickly raise it to a temperature that will melt the filler
alloy. Remove heat as soon as brazing is completed.
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