21
INSTALLATION AND SERVICE
System cleanliness
Compressor handling,
mounting and
connection to the system
Compressor handling
Compressor mounting
Compressor connection to
the system
System contamination is one of the
main factors aff ecting equipment
reliability and compressor service life.
Therefore it is important to
ensure system cleanliness when
manufacturing a refrigeration system.
During the manufacturing process,
system contamination can be caused
by:
• Brazing and welding oxides
• Filings and particles from
removing burrs from pipe-work
• Brazing fl ux
• Moisture and air.
Only use clean and dehydrated
refrigeration grade copper tubes and
silver alloy brazing material. Clean
all parts before brazing and always
purge nitrogen or CO
2
through the
pipes during brazing to prevent
oxidation. If fl ux is used, take every
precaution to prevent the leakage of
fl ux into the piping. The use of gas fl ux
core or fl ux coated braze wire or rod
instead of brush applied paste fl ux is
strongly recommended. Do not drill
holes (e.g. for schräder valves) in parts
of the installation that are already
completed, when fi lings and burrs can
not be removed. Carefully follow the
instructions below regarding brazing,
mounting, leak detection, pressure test
and moisture removal. All installation
and service work shall only be done
by qualifi ed personnel respecting all
procedures and using tools (charging
systems, tubes, vacuum pump, etc.)
dedicated for the refrigerant used.
Danfoss MPZ compressors are provided
with a lifting lug. This lug should
always be used to lift the compressor.
Once the compressor is installed, the
compressor lifting lug should never be
used to lift the complete installation.
Keep the compressor in an upright
position during shipping and
handling.
Mount the compressor on a horizontal
plane with a maximum slope of 3
degrees. All compressors are supplied
with four rubber mounting grommets,
each complete with metal sleeves and
nuts and bolts. Refer to the outline
drawings on page 10.
These grommets largely attenuate
the compressor vibration transmitted
to the base frame. The compressor
must always be mounted with these
grommets. Recommended mounting
torque: 12 - 18 Nm.
New compressors have a protective
nitrogen holding charge. The suction
and discharge caps should only be
removed just before connecting the
compressor to the installation to
avoid air and moisture entering the
compressor.
Whenever possible the compressor
must be the last component to be
integrated in the system. When all
brazing is fi nished and when the total
system is ready, the compressor caps
can be removed and the compressor
can be connected to the system with a
minimum exposure to ambient air.
In this situation nitrogen or CO
2
must
be purged through the compressor
via the process tube to prevent air
and moisture ingress. Purging must
start when the caps are removed
and maintained during the brazing
process.