the filter will not come out of the housing
i can rotate it with some difficulty but it appears to be held in the centre

d.cameron, November 2007

We had same problem yesterday.
The Filter is Sticking on the Center Post that contains the Spring-Loaded By-Pass Valve.
Just use a Flat-Blade Screwdriver to Gently Pry Off the Yellow Filter from the Center Post. Insert the Screwdriver at an angle just below the Yellow Plastic Surface of the Filter & Gently Twist & Pry as you move the Blade around the Inner Circle.
Good Luck

PS: Dyson Reccommends that this Foam Pre-filter be cleaned & Washed every 12 Hours of Operation. Be sure to Dry it Completely before Re-Inserting.
When reassembling be sure to put the By-Pass Valve Assembly together correctly. Black Cylinder first, then spring, then Black Cap, then Filter Assembly.

Leo & Joyce, November 2007

If this is the first time of taking the filter out, it will probably be have grit in there making it difficult to remove, basically brute force will get it out. There is nothing holding the filter in.

Stuart., November 2007