>
> > So the real question is: Was my carpet so dirty that even a
> > professional machine would have taken 2 -3 passes, or are these
> > machines just not powerful enough to get all the dirt out in one pass? >
> The major advantage to a professional machine is the massive suction
> power. Any old beast will loosen the dirt. But no rental from the
> supermarket is going to have any where near the suction of a
> truck-mounted machine. No matter how much dirt you suck out, or how many
> passes you make, there's still going to be a lot of it that sinks down
> into the backing, and the pad, that will not come out. I think that's
> what makes carpets so dirty so quickly after they've been cleaned > incompletely.
>
> But keep us posted as you go along, and a few months down the road.
When it gets dirty fast after that is because soap is left behind. I wet carpet with the soap as directed. Then use clean water to rinse and suck the carpet. I do this twice. it gets all soap out. The published directions are to make it easier to do not what is best.