Pulsation muffler in the ECO suction gas line

The direct connection between the ECO connection and the profile area produces pressure pulsations which, depending on the operating conditions, can result in resonance vibrations in the ECO suction gas line. This is why for some BITZER screw compressors special pulsation mufflers have been developed which largely avoid repercussions on the pipework and the liquid subcooler.

Compressor series CSH65 and CSH75 and CSV.

External pulsation muffler forming a unit with the ECO shut-off valve (rotalock valve) (Pipe layout of the ECO suction line and Mounting the pulsation muffler of CSVH compressors).

Compressor series CSH85 and CSH95

Internal pulsation muffler forming a unit with the ECO shut-off valve (rotalock valve), this unit being mounted in the ECO channel (Pipe layout of the ECO suction line).

Compressor series CSW65 .. CSW105 and CSH76 .. CSH95

By limiting the ECO operation to full load conditions and applications at relatively low pressure ratios, only minor pressure pulsations occur in the ECO suction gas line. In most cases, no pulsation muffler is required. However, the general criteria for pipe laying are the same as for CSH and CSV compressors (Pipe layout of the ECO suction gas line and Pipe layout of the CSV series).

Compressor series HS.85

Internal pulsation muffler forming a unit with the ECO shut-off valve (rotalock valve), this unit being mounted in the ECO channel (Pipe layout of the ECO suction line and pulsation muffler).

Compressor series HS.95

The muffler SD42 can be installed horizontally and vertically in the pipework.

OS.A95 and OS.A105: Pulsation muffler during economiser operation

For OS.A95 and OS.A105 compressors in ECO operation, a pulsation muffler in the economiser line is recommended resp. necessary. Two options are available:

Muffler system, consisting of muffler, check valve, control valve
Basic pulsation muffler SD42 in the ECO connection, part no. 354 004 05

For operation at condensing temperatures > 40°C and/or evaporation temperatures > 10°C, the muffler system is mandatory. In the remaining range, BITZER recommends the pulsation muffler SD42. For details see the following figure and table.

Application limit of OS.A95 and OS.A105 screw compressors during ECO operation, In the shaded area. the ECO muffler system is mandatory.
OS.A95 and OS.A105 compressors during ECO operation: recommended pulsation mufflers and combination with capacity regulation

Planned operating range

Pulsation muffler

Possible scope of capacity regulation

Operation in the shaded area of the application limit (tc > 40°C and/or to > 10°C)

Economiser muffler system is mandatory

  • Slider 80% .. 100% and fixed frequency 50/60 Hz
  • or slider 100% and variable frequency 25 .. 67 Hz

Operation outside the shaded area of the application limit (tc < 40°C and to < 10°C)

Optional: economiser muffler system

  • Slider 80% .. 100% and fixed frequency 50/60 Hz
  • or slider 100% and variable frequency 25 .. 67 Hz

Optional: basic pulsation muffler SD42 in ECO connection

  • Slider 80% .. 100% and fixed frequency 50/60 Hz

See also: