Sound and vibration management
Compressor
model
R404A
R452A
R454C/R455A
50Hz
60Hz
50Hz
60Hz
50Hz
60Hz
NTZ048-4
72
75
73
75
68
69
NTZ068-4
69
74
71
74
71
72
NTZ096-4
82
85
80
82
-
-
NTZ108-4
76
80
78
80
-
-
NTZ136-4
77
80
78
80
-
-
NTZ215-4
86
88
83
84
-
-
NTZ271-4
86
88
82
84
-
-
Operating conditions : Evap temp -35°c, Cond temp 40°c, SH10K
Acoustic hood available as accessory can reduce noise level by 6 to 10dBA
Vibration
Sound
The mounting grommets delivered with the
compressor should always be used. They will
largely attenuate the compressor vibration
transmitted to the base frame. These rubber
grommets have been selected and calculated in
accordance with the vibration frequencies that
are typical for the compressor. For that reason
other grommet types or brands shall not be
used.
The base on which the compressor is mounted
should be sufficiently rigid and of adequate mass
to ensure the full effectiveness of the mounting
grommets. The compressor should never be
rigidly mounted to the base frame otherwise
high vibration transmission would occur and
the service life reduced. Suction and discharge
lines must have adequate flexibility in 3 planes.
Eventually vibration absorbers may be required.
Vibration is also transmitted by the refrigerant
gas. Maneurop® NTZ compressors have built-in
mufflers to reduce pulsation. To further reduce
vibration an extra discharge line muffler can be
installed.
Compressors in operation are one of the sources
of sound and vibration in a refrigeration system.
Both phenomena are closely related.
Sound produced by a compressor is transmitted
in every direction by the ambient air, the
mounting feet, the pipework and the refrigerant
in the pipework. The easiest way to reduce the
sound transmitted through ambient air is to fit
an acoustic hood accessory. Because Maneurop®
NTZ compressors are 100% suction gas cooled
and require no external cooling they can be
insulated or enclosed in a sound proofing
material lined compartment.
Sound transmitted by mounting feet, pipework
and refrigerant should be treated the same way
as vibration (see next section).
25
AB245486497018en-000601
Application Guidelines
