Dräger FPS 7000 Manuel Technique page 15

3.4.2 Test with sealed exhalation valve
(FPS 7000 RA/PE/ESA/P)
1. Remove the exhalation valve disc.
2. Insert the exhalation valve test plug.
3. Produce a negative pressure of 10 mbar.
4. If the pressure drop is less than 1 mbar/min, remove the
exhalation valve test plug and insert the new valve disc.
5. Repeat the leak test. (see "Checking for leaks", page 14).
If the mask still leaks, carry out the leak test under water
(see "Leak test under water", page 15).
3.4.3 Leak test under water
It is not possible for a leak test under water to be performed
for the FPS 7000 RP with COM.
1. Remove the communication system in order to improve
visibility of the face seal.
2. Immerse the test head, including the FPS 7000, in water.
3. Produce a positive pressure of approx. 10 mbar.
4. Slowly turn the test head under the surface of the water.
Emerging air bubbles indicate leaks.
5. Take the test head with the FPS 7000 out of the water,
repair the FPS 7000 and replace any leaking components.
6. Repeat the leak test (see "Checking for leaks", page 14).
3.4.4 Checking the opening pressure of the
sealed exhalation valve (FPS 7000
RA/PE/ESA/P)
The opening pressure must be at least 4.2 mbar at a constant
flow of 10 L/min. If this opening pressure is not achieved, turn
the valve disc to remove dust particles or similar between the
crater and the valve disc. Then repeat the test.
If the opening pressure is still not achieved, replace the spring
(see figure A4-28 on the fold-out page) and repeat the test.
3.4.5 After testing
1. Disconnect the adapter.
2. Remove the facepiece from the test head and dry it if
necessary.
FPS 7000 RA/PE/ESA/P: Fit the exhalation valve cover
so that it clicks into place.
3.5 Replacing the speech diaphragm
1. FPS 7000 RP: Remove the mouthpiece if necessary.
Disconnect the inner mask.
2. Unscrew the speech diaphragm with the speech
membrane wrench and remove it.
3. Visually inspect the speech diaphragm and O-ring and
replace them if necessary.
4. Insert the O-ring, then screw in the speech diaphragm.
5. Attach the inner mask.
FPS 7000 RP: Fit the mouthpiece if necessary.
Technical manual | FPS 7000FPS 7000 RP
3.6 Replacing the exhalation valve
3.6.1 Mask with RA-type connector
1. Open the exhalation valve cover.
2. Disconnect the valve disc.
3. The valve disc and valve seat must be clean and
undamaged. Otherwise clean or replace them.
4. Fit the valve disc.
5. Close the exhalation valve cover.
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Maintenance work
15