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VPAP® III, VPAP III ST, VPAP III ST-A Service Manual
Appendix B: Noise reduction upgrade
To reduce the noise level of a VPAP III or VPAP III ST unit (with serials numbers earlier than
20040018972), you may prefer to perform the build standard upgrade rather than replacing the
motor. To perform the build standard upgrade it is necessary to make the following changes:
1 Add 4 x R300-7017 blower top foam pads to the volute.
2 Add 2 x R300-7017 blower top foam pads to the outside of the upper airpath.
3 Add 3 x R300-733 top foam pads to the lower airpath.
4 Fit a cable tie to the main power switch and replace the blower outlet connector.
Equipment required
• 6 x blower top foam pad part # R300-7017
• 3 x top foam pad part # R300-733
• Blower outlet connector part # R300-7018
• 1 x 100 mm cable tie
Adding foam pads to the blower assembly
1 Remove the blower assembly from the flow generator following the procedures outlined in
Section 5 Replacing major subassemblies
. Separate the upper airpath from the lower
airpath.
2 Remove the volute from the lower airpath.
3 Remove the backing from each self-adhesive foam pad and apply four foam pads to the volute.
When complete, the volute should have one foam pad on each of the four sides as shown:
