Installation
heat shield
C B
A
Compressor connection
System pressure test
Always use an inert gas such as nitrogen for
pressure testing. Never use other gasses such as
oxygen, dry air or acetylene as these may form
an inflammable mixture. Do not exceed the
following pressures:
When brazing the compressor fittings, do not
overheat the compressor shell, which could
severely damage certain internal components
due to excessive heating. Use of a heat shield
and/or a heat-absorbent compound is highly
recommended. Due to the relatively sizable
tubing and fitting diameters a double-tipped
torch using acetylene is recommended
for brazing operation on Danfoss SH scroll
compressors.
For brazing the suction and discharge
connections, the following procedure is advised:
.
Make sure that no electrical wiring is connected
to the compressor.
.
Protect the terminal box and compressor
painted surfaces from torch heat damage (see
diagram).
.
Remove the Teflon gaskets when brazing
rotolock connectors with solder sleeves.
.
Use only clean refrigeration-grade copper
tubing and clean all connections.
.
Use brazing material with a minimum of 5%
silver content.
.
Purge nitrogen or CO
2
through the compressor
in order to prevent against oxidation and
flammable conditions. The compressor should
not be exposed to the open air for extended
periods.
.
Use of a double-tipped torch is recommended.
.
Apply heat evenly to area
A
until the brazing
temperature is reached. Move the torch to
area
B
and apply heat evenly until the brazing
temperature has been reached there as well,
and then begin adding the brazing material.
Move the torch evenly around the joint, in
applying only enough brazing material to flow
the full circumference of the joint.
.
Move the torch to area
C
only long enough to
draw the brazing material into the joint, but not
into the compressor.
.
Remove all remaining flux once the joint has
been soldered with a wire brush or a wet cloth.
Remaining flux would cause corrosion of the
tubing.
In addition, for discharge connections equipped
with a non return valve integrated in discharge
fitting (SH180 to SH380) the direction of the
torch has to be as described on the picture, and
maximum brazing time should be less thant two
minutes to avoid NRVI damages.
Ensure that no flux is allowed to enter into the
tubing or compressor. Flux is acidic and can cause
substantial damage to the internal parts of the
system and compressor.
The polyolester oil used in SH compressors
is highly hygroscopic and will rapidly absorb
moisture from the air. The compressor must
therefore not be left open to the atmosphere
for a long period of time. The compressor fitting
plugs shall be removed just before brazing the
compressor. The compressor should always be
the last component brazed into the system
Before eventual unbrazing the compressor or
any system component, the refrigerant charge
must be removed from both the high- and
low-pressure sides. Failure to do so may result in
serious personal injury. Pressure gauges must be
used to ensure all pressures are at atmospheric
level.
For more detailed information on the appropriate
materials required for brazing or soldering, please
contact the product manufacturer or distributor.
For specific applications not covered herein,
please contact Danfoss for further information.
Maximum compressor test pressure (low side)
33.3 bar(g)
Maximum compressor test pressure (high side)
45 bar (g)
Maximum pressure difference between high and low
side of the compressor
37 bar
34
FRCC.PC.028.A5.02
Application Guidelines
