If your ducted vacuum suction is low or weak after replacing the bag, there may be a blockage of the motor filter screen. 

Here's a simple solution which may help get your ducted vacuum suction back to its best.

1. Remove the new bag from your ducted vacuum 
2. Remove the bag spacer/support from the bottom of the drum
3. Take a look at the bottom of the ducted vacuum drum, you should see 1 or 2 openings - often covered in mesh or a similar material - this is the motor filter screen
4. Make sure the screen(s) is clear of any lint, fluff or dust. It's a bit like cleaning out a clothes dryer filter. If there is quote a lot a fluff & dust sitting in the bottom of the drum, give it a wipe out with a slight damp cloth
5. Replace the bag spacer, the new bag & the lid
6. Test the ducted vacuum suction

In most cases this is the cause of low or weak ducted vacuum suction in systems which use bags.

If this does not solve the issue, there may be a blockage in the hose or pipework. Aussie Vac can provide an un-blocking service by contacting us here.

This how to video, for changing the bag, also looks at cleaning the motor filter screen.
Check it out..