Labconco 3970202 User Manual - page 33

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Chapter 6: Maintaining Your Filtered PCR Enclosure 

when downflow velocity drops below the recommended 30-65 fpm 

velocity and the speed control is adjusted to full speed. Replace 

HEPA filter if it fails the HEPA Filter Leak Test in Chapter 6. 

How to Install a New HEPA Filter  

NOTE:  Only a qualified certifier should service the HEPA filter.  

After the HEPA filter is replaced, the enclosure MUST be 

certified.  See Figure 6-1. 

1.  Unplug the enclosure and remove the prefilter located on 

top. 

2.  Remove the front panel by loosening the two screws that 

secure it. 

3.  Using a 9/16" deep socket, loosen the filter clamp bolts 

located on top.  Refer to Figure 6-1. 

4.  With the clamp bolts loosened, the HEPA filter-clamping 

frame should be clear of filter.  Carefully pull the filter 

straight out of the enclosure and discard properly. 

5.  Cover the surface of the new HEPA filter gasket with a 

light coating of silicone grease, if desired. 

6.  Install the new HEPA filter by pushing it straight into the 

cabinet, ensuring that it is correctly oriented with the gasket 

facing down on the exhaust side of the enclosure.   

7.  Tighten the clamp bolts uniformly until the filter gasket is 

properly compressed against the frame.  Inspect the seal 

thoroughly before proceeding. 

8.  Reinstall the front panel and prefilter. 

9.  Plug the enclosure in and have it check for leaks and 

downflow velocity. 

CAUTION:  The filter clamp bolts should only be tightened 

enough to ensure a proper seal at maximum tightness.  The 

filter gasket should be compressed 50% or less.