There is very little suction comming from the DC05 machine and the hose is not blocked and the filters are clean. There is a small vent on top about 50mm dia that a high pitched whistle is comming out of. Any ideas.

Brett, April 2008

Hi Brett

The little holes on the top are called bleed valves when they release air they make a whistling sound but it only releases air when the machine is blocked and does this so your motor can cool down before overheating so although you may think the hose is blocked and the filters are clean the machine is blocked somewhere thats why the bleed valves are releasing air so my advise is check the filters and check the extension tube and hose assembly good luck!! and a quick tip if you need filters www.sparesaver.com is very cheap and free delivery.

Dean, May 2008

Hi Brett

The little holes on the top are called bleed valves when they release air they make a whistling sound but it only releases air when the machine is blocked and does this so your motor can cool down before overheating so although you may think the hose is blocked and the filters are clean the machine is blocked somewhere thats why the bleed valves are releasing air so my advise is check the filters and check the extension tube and hose assembly good luck!! and a quick tip if you need filters www.sparesaver.com is very cheap and free delivery.

Dean, May 2008