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The sensor has to be used as a protection device, when the temperature of the discharge line
exceeds the limit – see Table 11.
Compressor
model
ZO(V)*AG
Table 11: Maximum allowed discharge line temperature
3.7
Filter screens
CAUTION
Screen blocking! Compressor breakdown! Use screens with at least
0.6 mm openings.
The use of filter screens finer than 30 x 30
be avoided with these compressors. Field experience has shown that finer mesh screens used to
protect thermal expansion valves, capillary tubes or accumulators can become temporarily or
permanently plugged with normal system debris and block the flow of either oil or refrigerant to the
compressor. Such blockage can result in compressor failure.
3.8
Mufflers
Gas flow through scroll compressors is continuous with relatively low pulsation. External mufflers
may not be required on Copeland scroll compressors.
Due to system variability, individual tests should be conducted by the system manufacturer to verify
acceptable levels of sound and vibration. If adequate attenuation is not achieved, use a muffler with
a larger cross-sectional area to inlet area ratio. A ratio of 20:1 to 30:1 is recommended.
A hollow shell muffler will work quite well. Locate the muffler at minimum 15 to maximum 45 cm from
the compressor for the most effective operation. The further the muffler is placed from the
compressor within these ranges, the more effective. Choose a muffler with a length of 10 to 15
3.9
Sound and vibrations
Figure 19: Example of suction tube design
Under some conditions, the Copeland scroll has a normal starting rotational motion that can transmit
a transient noise along the lines. This may be particularly pronounced in compressors using a three-
phase motor due to their inherently higher starting torque. This phenomenon, like the one described
previously, can easily be avoided by using standard line isolation techniques.
The sound level of a system is the result of design, quality and application. Scroll compressors sound
power levels generally increase with the compressor model capacity and the condition pressure ratio.
16
Discharge line
temperature limit
135 °C
mesh
(0.6 mm openings) anywhere in the system should
Vibrations during compressor operation can cause cracks which
could lead to refrigerant leakage. This situation must be avoided
by the system manufacturer/installer. To this end, the pipework
must be carefully designed when connecting a scroll compressor
to a system.
A scroll compressor makes both a rocking and twisting motion and
enough flexibility must be provided in the pipework to allow
starting, stopping and steady state running of the compressor
without transmitting excessive stress into any line attached to the
unit. In a split system, the most important goal is to ensure minimal
vibration in all directions to avoid transmitting vibrations to the
structure to which the lines are fastened.
cm.
AGL_Ref_ST_ZO_E_Rev00
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