Hi Russ,
Thanks very much for your reply......I guessed it might be something of the sort but good to know for sure. The DC14 also does not appear to have a filter in the similar housing on the side of the motor as per the DC07?......I guess it is replaced by the one on the top of the cyclone?..... So if this valve is faulty on a DC07 I guess there would be a loss of suction.....The one in a DC07 I was having a look at for a friend is broken... i.e. two of the retaining clips are broken so the spring could easily push the black plastic retainer out...... so I guess I will replace the complete filter housing & valve assembly?
Thanks very much for your help
John