[Paul Dunkley]

My Extraction machine is making a fog horn sound checked both motors seem fine, works for a bit and noise happens. Any ideas what it could be?

[Richard Cole]

Have you checked the wand for blockage? also vac pipe?

[Carpet Dawg]

also the waste tank lid and inside of the machine i.e. check for any loose gaskets. Mines was doing that before I glued it down.

[neilwebber]

Sounds like the vacuum seal isn't perfect.  Mine does the same occasionally, but I find that a British Standard clout works well, along with a bit of quiet swearing and finger wagging.