A ventless washer/dryer combo unit allows consumers to do all of their laundry in one machine, as the unit transitions from a washing cycle to drying. The hot air coming in to dry the clothes gathers the moisture and carries it back to a condensing chamber.
A ventless washer/dryer combo washes clothes through a process that is quite similar to that of stand-alone washing machines, progressing through cycles that wash and rinse the clothes before spinning as much moisture out of them as possible. Most ventless washer/dryer combo units use condensation to dry the clothes, using the warm air to pull moisture out of the clothes and cause it to condense in a separate chamber.
Some ventless dryers use the heat pump system, pushing the air through a heat pump. The process condenses water vapor and sends the air into a collection chamber, where the unit heats it again to use it to dry the clothes further. The heat pump type of dryer uses less energy than either traditional or condensation dryers.
The biggest difference between ventless and traditional dryers is the fact that the moisture from the clothes ends up in a condensation collection point instead of traveling through duct work and traveling outdoors.