There was no need for that last comment.
Drying carpet quickly isn't down to just one thing,
pre vacuuming will open the pile and take the lairs of dust away which would normally hold excess water if you were to pre spray first,
pre spraying will break up dirt before HWE therefore you don't have to lash water into the pile to break up the dirt.
Try a scrubbing machine after pre spraying but before HWE this will make your pre spray work better and quicker
Loads of dry wand strokes after cleaning will take plenty of excess water away.
Uses air movers or turbo driers, these dry the carpet better than any thing else.
Open a window in the room you are working in aswell as putting the heating on (both needed together)
Post buff carpet with woollen bonnet pads
Shaun