BRAZING/DEBRAZING PROCEDURES. - continued
Never use a heating torch on any part that contains refrigerant. Heat causes the
refrigerant to break down and form carbonyl chloride (phosgene), a highly toxic
and corrosive gas. All refrigerant must be discharged from the system and the
entire system must be purged with dry nitrogen before beginning any debrazing
It may be easier to access a component by cutting or debrazing the copper lines
in accessible areas and removing part of the interconnecting tubing with the
(3) If debrazing a joint on a valve, disassemble the valve to the extent possible and wrap all but the joint
with a wet cloth to act as a heat sink.
If heat is applied slowly, or only on one side of a joint, the entire component or
length of tubing will be heated and filler alloy in adjacent joints may also be
(4) Apply sufficient heat uniformly around the joint to quickly melt the filler alloy. Remove heat as soon as
the joint is separated.
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 wire brush. Be sure no filler alloy or other debris is left inside
any tubing, fitting, or component.
Nitrogen is an inert gas that can cause suffocation and must be discharged in a
well ventilated area.
The polyurethane foam used as insulation in the air conditioner will break down to
form toxic gases if exposed to the flame of a torch or brazing temperature. Work
in a well ventilated area.
(2) Protect insulation, wiring harnesses, and other components with appropriate heat shields.