I purchased a used Rainbow D4SE and wanted to know if it uses a hepa filter? If so, where is it at?

SOURCE: Motor replacement for Rainbow D4se

From the bottom, remove the screws separating the top and the bottom. Then at the bottom, remove the round water seal, take out those screws, ( careful with the water seal, reglue it with contact cement when you put it back on). At the top of the motor, take out the scres around the motor and it should pull out.

SOURCE: Hoover Z-400 - Hepa Filter

These filters should be changed at least once a year, they get clogged up and won't clean out. So I would try a new filter and go from there, make sure there are no clogs in the hose and down below where the dirt inlet is.

SOURCE: rainbow d4se assembly

Generic problem for all Vacuums
Rainbow d4se assembly
How to assemble correct movable fan gen., middle fan spacer, rexair d4 lower stage fan and so on? Which side goes first?

I would advise you to ALWAYS to FIRST UNPLUG YOUR VACUUM before beginning any service procedure.
You can change the fans on the RexAir / Rainbow vacuum but sometimes that is only a temporary fix, the fans would be new but the rest of the motor may burn out sooner with the added load to the motor and sometimes it is more cost efficient to replace the motor than to repair it and have it break down or burn up the motor, as far as the spacing
You can refer to the nearest vacuum cleaner dealer in your area or in the yellow pages or call the RexAir/Rainbow factory for a schematic of the breakdown of the motor, and you can also cal the factory or check the website and download the owners manual from the website.
http://rainbowvacuum.com Customer Service
1-248-643-7222 Monday thru Friday from 9:00 am to 5:00 pm EST
Don – The Vac Man

Debra V

• 101 Answers
• Posted on Oct 12, 2008

SOURCE: Hepa filter does not rotate

I just fixed my HEPA filter not rotating!!

It involves taking apart the vacuum HEPA area. All screws are the same size. There are a LOT of 'em. Really straightforward putting it back together too.

ok, once you take the HEPA canister area off the vacuum, careful with the wires! Unplug them from the controller board. You open up the HEPA chamber by removing more screws until you see where the motor that turns the filter is mounted on the side. Remove motor from the green chamber. Note where the washer goes. Once the motor is off, you'll see that the center hub that drives the HEPA filter is rounded out. What I did was jam little bits of aluminum from a pop can into the space between the circle and the square to force the walls back to square. I started by folding a little piece of aluminum over and over so it was about three layers thick. Jammed that in. That wasn't quite enough thickness so I shoved another piece with it. If you can find something that is about 4 times the thickness of a pop can aluminum, that'd probably work too. Slight wedge shape on the tip would help. Any sort of tiny shim.

To test your work, just put a couple of holder screws into the HEPA cannister housing, plug in the cover/switch, plug in the HEPA moter. Turn it on for a few seconds to make sure the filter turns. Then you can add more thickness to the hub or put things back together.

SOURCE: want to replace HEPA post filter

http://www.dyson.com/customercare/manuals/us/dc07_manual_us2007.pdf

here is the link to your owners manual. scroll down to page 6 it shows you the filter to clean and how to take it aprt.