Carrier 42XQ Series Installation And Start-Up Instructions Manual page 14

To make the connection between the
refrigerant pipes of the respective service
valves, proceed as follows:
a) If necessary, weld the pipes that link the
outdoor and
phoscopper solder and solder flux to
prevent the formation of copper
oxide. Release nitrogen flow during
the welding.
b) Attach the nuts which are pre-fitted
in the connections of the indoor and
outdoor units to the ends of the
suction and fluid pipes.
c) Once item "b" has been performed,
create the flanges at the end of the
pipes. Use a flange at the end of the
pipes. Use a flange of a suitable
diameter.
d) Connect the two flange nuts to the
respective service valves.
IMPORTANT !!!
Avoid loosening the connections after
tightening them to prevent loss of refrigerant.
Flanging procedure
Cut the copper pipe to the appropriate size
using a pipe cutter.
It is recommended to cut approximately 30 to
40mm more than the estimated size.
IMPORTANT !!!
Remove the burrs from the end of copper pipe
using a suitable tool (of the rosqueira type),
keeping in mind that a copper burr in the
refrigeration circuit could cause serious
damage to the compressor. This procedure
is very important and must be performed with
great care.
NOTE
When removing the burrs, make sure that the
end of the pipe is turned downwards to prevent
any particles falling inside the pipe.
14
indoor units with
Remove the flange nut from the unit and
position it with care in the copper pipe. Create
the flange at the end of the pipe using a
flange.
Insert a plug or seal the flanged pipe with
adhesive tape to prevent dust or humidity
entering the pipe until it is used.
Take care to place refrigeration oil on the
surfaces in contact between the flanged end
and the joint, before connecting them
together. This is done to prevent any loss of
refrigerant.
To achieve a good joint, keep the coupling
pipe and the "flare" pipe firmly connected
while performing a slight manual threading.
Then press firmly.
Fig. 20