A wet vac is a whole different ball game to a carpet extractor. We've had Numatic wet vacs for years and never had to replace a motor even though we were often sucking water through them. They have peripheral motors rather than tangental as most carpet extractors have the exception being Craftex machines.
A carpet extractor is pulling against a blockage all the time, i;e the carpet pile and is nearly always sucking hot moist air. Wet vacs with a hard floor pickup have a lot more air going through them and usually dealing with cold substances.
